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1993 400E Head gasket, Yay or Nay?

Kyiv

1993 400E | Azov мой кумир!
Member
Hi all,




  • I've got a US 1993 400e with 108k miles. Owned the car for 2.5 years since it had 98k miles.
  • It's a California car and it spent most of its life here. Car drives very well with full power.
  • When i bought it, it was in very good condition. I've since invested about $14k in it. $9k in preventive maintenance and $5k in transmission rebuilt + repair concerning radiator/fan clutch etc.
  • Since day one temperature in the city would hit 105C then be brought down by kickin-in fans, then repeat all over. Temperature never ever went above 115C on my watch, and that's in a fully loaded car, going uphill on freeway, on 100C day, 85 mph at full throttle.
  • Eventually i did transistor mode, and now my car almost never touches 100C.
  • Used oil analysis show no coolant in the oil at all, and is perfect report


I took it to specialized-in-mercedes-only mechanic last week, and he's telling me it's a head gasket. Per mechanic, the large front hose by the radiator is stiff after 10 minutes from start up, and removing cap causes coolant to bubble over. $4,300.

What do you all think? Your thoughts are much appreciated.​






 
Re: Head gasket, Yay or Nay?

There is a chemical test for coolant to determine if exhaust gases are present. These motors are robust and I'd be very surprised if you needed a headgasket- very surprised. Not against maintence, but 9k... that's a wee bit excessive given the mileage.

I've only owned 2 of these and not seen the type of temps you report. I presume you are driving in a 100F and not 100 celcius... Transistor mode- cool harness masks the problem and is not a cure. Maybe get with some other members in LA for shop suggestions and get at least a second opinion.

Michael
 
Re: Head gasket, Yay or Nay?

At the very least, you should get a second opinion from another shop.

What have you done so far to the cooling system? Radiator, viscous fan, thermostat?
 
Re: Head gasket, Yay or Nay?

[*]Since day one temperature in the city would hit 105C then be brought down by kickin-in fans, then repeat all over. Temperature never ever went above 115C on my watch, and that's in a fully loaded car, going uphill on freeway, on 100C day, 85 mph at full throttle.
[*]Eventually i did transistor mode, and now my car almost never touches 100C.
If the electric fans reduce temp at speed, your fan clutch is not working properly (i.e., not engaging at a low enough temp). These engines should very rarely exceed 100-105C when the cooling system is working properly; and they should not need the resistor mod to run the electric fans more often. However - this is probably not related to your issue below.


I took it to specialized-in-mercedes-only mechanic last week, and he's telling me it's a head gasket. Per mechanic, the large front hose by the radiator is stiff after 10 minutes from start up, and removing cap causes coolant to bubble over. $4,300.

What do you all think? Your thoughts are much appreciated.
I've seen a couple of M119's with this phenomenon. If fluids are not mixing, and there are no other problems (i.e., not losing coolant, etc) I would just keep driving the car. As mentioned above you can get a DIY test kit to check for combustion gasses in the cooling system, but this may or may not be a head gasket. It's also possible there is a tiny crack in the head or block allowing combustion pressure into the cooling system, but not allowing liquid into the cylinder. If it were a head gasket, I think it's likely you'd have liquid going the other way too. You won't be happy (neither will your shop) if you end up with the identical problem with new head gaskets. While the heads are off it would be good to have them refreshed (new valve stem seals, etc) which will spike the cost even higher.

$4300 for only head gaskets is poor ROI, IMO. You could get a low-mile replacement engine for a fraction of that, re-seal it on the engine stand, and swap motors for probably the same money (much less as DIY). Or use this opportunity to swap in a 5L engine.

If symptoms are bad enough that you cannot keep driving the car, I would at least consider trying a sealing product like this one before plunking down >$4k.

:hornets:
 
Re: Head gasket, Yay or Nay?

What should be the cost of repairing a headgasket? And is there a how to on this site for it?
 
Re: Head gasket, Yay or Nay?

What should be the cost of repairing a headgasket? And is there a how to on this site for it?
Figure roughly 20-40 hours labor for a professional mechanic who has done the job before (not sure of the exact book time), probably twice that for a first-timer. And, probably $1k-$2k in parts, which includes a lot of "while you are in there" parts. If you replace one, I'd replace both, as 80% of the work is already done to remove the first head... the second head removal is incremental. While the heads are off they should be inspected by a machine shop, if valve guides are needed or any machine work, that's additional cost.

I'd expect $4k-$5k USD total from typical indy shops in USA as a rough guide assuming no machine work required.

If anyone has official quotes (or, had this job done and has an accurate itemized receipt) I'd love to hear if my wild estimates are remotely close or not.

There is no HOW-TO that I'm aware of as very, VERY few M119's ever need the heads removed. There was an extensive thread on BenzWorld in 2008 or 2009 with lots of photos, the work was done on a 500SEL with M119 engine, by a fellow named Patrick Hamilton. See if you can find that thread, it may have useful information.

:v8:
 
Re: Head gasket, Yay or Nay?

So I abstracted from my car for almost 12 months. Didn't even drive it for the last 6 months. With clear head and complete emotional disinvestment I've washed it, got it a new battery and just performed a head gasket chemical test (blue liquid, suck in air through expansion tank when thermostat has opened) and the liquid stayed completely blue.
I did about 30 pulls of air from expansion tank in batches of 5 in 6 sets - still the liquid stayed perfect blue. The temp of the coolant reached 95C.

I also did a UOA about 15-16 months ago that showed zero coolant in the oil.

To remind, the car from day one would bounce of 105C - be brought down by fans, repeat cycle (car mostly driven in thick LA traffic). If I'm on the freeway with no traffic, temp stays at 85C-90C. If going uphill coolant gauge moves up. Never saw the gauge go above 110C. Drove the car at 140 MPH, took it on 500-600 miles road trips with WOT.

*new radiator
*new fan clutch (mercedes OEM)
*correct MB coolant


What is the chance that it still can be head gasket?


Thanks
 
Re: Head gasket, Yay or Nay?

Just a stab in the dark from an amateur, nay, a total novice:

- If the overheating is occurring when going uphill, but the cooling system is otherwise fine (new radiator/viscous-fan-clutch/thermostat/etc) then could it be that excess exhaust back pressure (crushed exhaust pipe? plugged cat?) is causing the engine to get hot? And of course going uphill means the engine is already working harder?

- Are you certain the gauge is accurate? Can you swap gauges?
 
Re: Head gasket, Yay or Nay?

Have you had a water pump yet?

My UK car was the same. I replaced Radiator, Fan Clutch, Water Pump and Thermostat. My car has never gone over 85 since.
 
Re: Head gasket, Yay or Nay?

If it's not boiling over, don't worry about it.

You live in the desert. Cars have a hard time running 100% cool. It would appear it's a fan clutch problem, but you said it's been replaced.

I have a 5.0 m119 in my garage that had a blown headgasket. It had coolant running down into the valley under the intake. It left streaks of white crusties. So maybe look for an external leak. But if it's not overheating, it's nothing to be concerned about.

FYI-headgaskets are a bastard of a job. I have my own mechanics shop, 5 grand would be around what it would take to motivate me to do that job again. It's horrid.
 
Re: Head gasket, Yay or Nay?

Re-reading this again... the ONLY issue here is a firmer-than-normal upper radiator hose, and bubbling in the reservoir when the cap is removed hot (something you should never do)...? Sounds to me like you have no problems.

See what I wrote in post #5 again. Your mechanical fan clutch is not engaging at the proper temp if the "resistor mod" is keeping the temps down; the temps cycling between approx 95-105C without the mod is a classic symptom of a fan problem, yes even with a new Sachs/Horton clutch. Search the forum for discussion about the OEM fan clutch engagement / calibration issues.

I agree with Raffaelli: if you don't have coolant loss, and temps are not exceeding 110C, there's nothing to be concerned about. Drive it and relax. And there's no way I'd replace the head gaskets based on what you've described.

:tumble:
 
Re: Head gasket, Yay or Nay?

I've got an UPDATE. The car just received a new water pump and ceramic resistor that's located behind the left headlight. So thus far cooling system received all of the NEW parts it consists of:


  • radiator
  • fan clutch
  • thermostat
  • water pump

`New water pump DID NOT resolve the issue


To remind:


  • Have the car since August 2014 and have put 13k miles on it (111k on the odo right now)
  • car has NEVER overheated on me
  • I have transistor mod where fans aux fans kick in at 98C instead of 105C
  • After warming up, does repeated 98C to 82C - in stop and go traffic. Timed it, every 2 minutes. Auxiliary fans drop temperature to 82C very quickly with out any struggle
  • Cooler weather seems to have a positive effect, but it's slight
  • If I'm freely moving, I can drive for 30 minutes with out coolant temp touching 98C, stay at 90C or below. Any slow-downs and stops will cause 98C-82C cycle, albeit at longer than every-two-minutes intervals. Moving seems to lessen severity of the issue
  • no coolant present in UOA
  • exhaust gases test showed no presence in coolant


GSXR says it's either:

1. still fan clutch issue
2. "It's also possible there is a tiny crack in the head or block allowing combustion pressure into the cooling system, but not allowing liquid into the cylinder"

My car received new fan clutch in late 2014, but the issue was present since day one, meaning on BOTH fan clutches.
QUESTION: Is it possible for a tiny crack in the head or block to be there for 4.5 years with out symptoms getting worse? Recent dyno test showed healthy # of HP. Car starts every time. Very good power.
 
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Re: Head gasket, Yay or Nay?

If I'm understanding correctly - the electric fans turn on and rapidly drop the engine temp. This proves the liquid portion of the cooling system is working, but you are lacking airflow... which means the mechanical fan clutch is likely freewheeling more than it should. If you read the MANY threads on this forum discussing the fan clutch, it's known that even new ones from the dealer can be "defective" (more accurately, mis-calibrated) out of the box. Klink mentioned having to test out 10 new OE/dealer clutches to find 1 that worked properly. But anyway:

1) If the primary concern here is the firm radiator hose - stop squeezing it.

2) If the primary concern here is the engine temp won't stay at 82C all the time - stop expecting it to. There is nothing wrong with temps of 95-100C. (I'm also assuming the dash gauge is accurate, btw.) Your fan clutch is still suspect though since the electric fans drop engine temp; and the electric fans were never intended to provide primary cooling below 107C.


If you wanted to toss more money into testing, install an ACM fan clutch ($150 at FCP). The ACM clutch is engaged almost all the time, and may keep the temps lower, or more consistem. If it works, and you don't mind the constant roaring, you can leave it installed (and then remove the resistor mod that turns the fans on early).

Anyway, sure, it's possible a tiny crack could exist somewhere and not get any worse. But the crack doesn't seem to be causing a problem, i.e. it would not be the reason the electric fans cycle from 98-82-98.

:klink3:
 
Re: Head gasket, Yay or Nay?

A significant number of the factory fan clutches are mis-adjusted even when new. You may have experienced this.
 
Re: Head gasket, Yay or Nay?

By the way, I have found that running temperatures are EXTREMELY dependent on ambient temperatures, as well as humidity levels.

I never had much in the way of alarming temperatures when I lived in the temperate Pacific Northwest with my E500. Temps would be in the 85-100C range.

When I moved to Texas, and drove the car in high ambient temps (90+F) and high humidity -- about 6-7 months of the year -- I found that temps would run 100-115C. Higher temps when running the car at high speeds.

I replaced the original fan clutch at around 125K miles with one from a 1992 500E, that had around 52K miles on the odometer. This fan clutch, I found, only "reduced" temperatures perhaps 3-5 degrees Celsius. You could reduce temps more by turning off the A/C, in hot climates.

When I moved to Maryland 16 months ago, I found that the car does run hot (i.e. 100-115, same as Texas) in hot and humid summer Maryland ambient temps. However, in fall and winter, I am finding the car runs nice and cool -- in the 85-92C range. There's no way I can get the car anywhere near 100C in winter (30s and 40s temps) even if sitting idling for 5-10 minutes, or driving the Dulles Airport Toll Road at 90-95 MPH because I'm late for a flight).

I have a new factory MB fan clutch that I have been meaning to install in the car, to see if there is any change. I will do this in the spring ahead of the summer temps.

The bottom line, is that the car is very sensitive to ambient temperatures, and wide fluctuations depending on engine load, and ambient temps, WILL happen. It is not an OMG moment to have the car running at 110C, in the middle of a 85+F summer day with the A/C blasting, and you are traveling at 75MPH or higher. If your car was running 110C at low ambient temps (say, 30s and 40s Fahrenheit), then I think you would have more cause for alarm.

Cheers,
Gerry
 
Re: Head gasket, Yay or Nay?

I recently saw similar temps in a bit hotter/humid environment. It turned out I had failed to tighten the clamp on the lower expansion tank feed when cleaning. This did produce a loss of coolant however it was not significant. Could it be that the hose from the expansion tank to the overflow tank behind the fender is letting out pressure but not coolant? High point in the system and tends to be ignored. Also the "firm" return hose to the radiator?

drew
 
Re: Head gasket, Yay or Nay?

If I'm understanding correctly - the electric fans turn on and rapidly drop the engine temp. This proves the liquid portion of the cooling system is working, but you are lacking airflow... which means the mechanical fan clutch is likely freewheeling more than it should. If you read the MANY threads on this forum discussing the fan clutch, it's known that even new ones from the dealer can be "defective" (more accurately, mis-calibrated) out of the box. Klink mentioned having to test out 10 new OE/dealer clutches to find 1 that worked properly. But anyway:

1) If the primary concern here is the firm radiator hose - stop squeezing it.

2) If the primary concern here is the engine temp won't stay at 82C all the time - stop expecting it to. There is nothing wrong with temps of 95-100C. (I'm also assuming the dash gauge is accurate, btw.) Your fan clutch is still suspect though since the electric fans drop engine temp; and the electric fans were never intended to provide primary cooling below 107C.


If you wanted to toss more money into testing, install an ACM fan clutch ($150 at FCP). The ACM clutch is engaged almost all the time, and may keep the temps lower, or more consistnt. If it works, and you don't mind the constant roaring, you can leave it installed (and then remove the resistor mod that turns the fans on early).

Anyway, sure, it's possible a tiny crack could exist somewhere and not get any worse. But the crack doesn't seem to be causing a problem, i.e. it would not be the reason the electric fans cycle from 98-82-98.

:klink3:

1. I wan't the one squeezing upper radiator hose. It was mechanic who told me I needed a head-gasket.

2. I just ordered new coolant temperature sensor just to rule it out 100%.

3. I dont expect a stable 82C, but every two minutes 98-82-98-82 in stop-and-go-traffic is definitely wrong. I'll dig into fan clutch threads tonight. I browse this site a lot, and encounter mentions of bad new fan clutches, but never stepped on a thread that actually explains it, yet

4. I wanted to do water pump before attacking fan clutch again because it anyways needed to be replaced after 26 years of service

By the way, I have found that running temperatures are EXTREMELY dependent on ambient temperatures, as well as humidity levels.

I never had much in the way of alarming temperatures when I lived in the temperate Pacific Northwest with my E500. Temps would be in the 85-100C range.

When I moved to Texas, and drove the car in high ambient temps (90+F) and high humidity -- about 6-7 months of the year -- I found that temps would run 100-115C. Higher temps when running the car at high speeds.

I replaced the original fan clutch at around 125K miles with one from a 1992 500E, that had around 52K miles on the odometer. This fan clutch, I found, only "reduced" temperatures perhaps 3-5 degrees Celsius. You could reduce temps more by turning off the A/C, in hot climates.

When I moved to Maryland 16 months ago, I found that the car does run hot (i.e. 100-115, same as Texas) in hot and humid summer Maryland ambient temps. However, in fall and winter, I am finding the car runs nice and cool -- in the 85-92C range. There's no way I can get the car anywhere near 100C in winter (30s and 40s temps) even if sitting idling for 5-10 minutes, or driving the Dulles Airport Toll Road at 90-95 MPH because I'm late for a flight).

I have a new factory MB fan clutch that I have been meaning to install in the car, to see if there is any change. I will do this in the spring ahead of the summer temps.

The bottom line, is that the car is very sensitive to ambient temperatures, and wide fluctuations depending on engine load, and ambient temps, WILL happen. It is not an OMG moment to have the car running at 110C, in the middle of a 85+F summer day with the A/C blasting, and you are traveling at 75MPH or higher. If your car was running 110C at low ambient temps (say, 30s and 40s Fahrenheit), then I think you would have more cause for alarm.

Cheers,
Gerry

Gerry,

So in high temp, high humidity climates your car tends to run at 100-115C, with being warmer at higher speeds and lower temp in traffic? Could you please elaborate a little more as to when you see 100C and when do you see 115F, as far as traffic, engine load etc?
I'm live in northern VA since March 2018, and the cooler it is the better-ish my situation, but not very significantly (10-30% at most). At the core, the issues is always there
 
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Re: Head gasket, Yay or Nay?

I apologize in advance for the Klink-style and Klink-level rant below.


I don't see that there's a problem with the temp climbing to 98C at idle and then going back down and then up again (in my opinion). I think that's the way the system is supposed to work. If the car is running in moderate (50s-70s) ambient temperatures, those are wonderful temperatures to have. The fact that the cooling system is doing its job and it is going down is IMHO a good thing.

In high-temp (85+F ambient), high humidity summer climates, yes, when my car is running at 70+ MPH speeds with the A/C running, it is entirely not unusual to see 105-110C temperatures. When running at slower speeds in these ambient conditions, 95-105C is the norm (the fans control the temp....when it rises, the aux fan comes on and forces it down). This is with A/C running.

If A/C is NOT running, temps are generally ~5C lower in all cases.

If idling on a hot day, for a long period (say, in a parking lot), 110-115C temps are not uncommon, before the aux fan kicks in and forces the temp down.

Here are the things that I have learned over the years -- with regard to cooling:

  1. MBs show the ACTUAL temp indicated on the gauge. Including variances and fluctuations while the car is running, in all conditions. This is different from nearly every other type of car out there; most cars tend to indicate a standing "mid-point" on the temp gauge that covers a range of operating temps, and the needle doesn't move. This means that the needle on MOST cars (other than warm-up) only moves when the car is basically overheating or very close to it -- essentially when the coolant temp is beyond the pre-programmed "safe zone temp range" where the needle stays put.
  2. People MUST stop freaking out about MB (M103, M104, M119, M117, etc.) temps that go over the 100C mark. It is ENTIRELY FINE for any MB of our era to operate at temps of 115 and less. A temp of 100C is 10000000% NORMAL ... it is not bad, not an anomaly, and completely normal.
  3. The second-stage aux fan typically kicks in around the 105-110C range. This provides an extra boost of cooling that helps push the temp down, if working correctly. The 105-110C range, again, is NOT "OMFG MY CAR IS OVERHEATING AND DYING" territory. It is an elevated temperature, but it is not detrimental, even if run for long periods.
  4. If your car is getting to 115C and beyond (even on a hot day), then there is likely an issue that needs to be diagnosed and addressed. This may be something as simple as the second-stage of the fan not kicking in, a faulty coolant temp sensor, water pump, fan clutch, radiator, etc.
  5. Fan clutches, in proper working order, can be very very powerful and almost completely negate the need for aux fans. My M117 (560SEC), which has a new Behr fan clutch that I installed in Texas a few years ago, roars like a jet plane when it engages. It can take my engine, operating at 100C, down to 85C in a matter of seconds when running at freeway speeds.
  6. Certain engines do tend to run cooler or hotter, depending on the application. For example, the M119 as used in the E500E, is very very tightly packed into the engine compartment. There is NOT a lot of room for air to circulate in there. This relative lack of air circulation does not help overall cooling and running. I have always found (after owning three of them) that M104 engines also tend to run a bit hotter overall than other engines, like the M119 as used in the E500E. 100C seems to be a "mean" normal temp for these engines. This is OK.
  7. My M117 engine as used in the 560SEC tends to run cooler (85-90C) than my M104s and M119 has. This is likely partly because there is more air circulation room underhood. But even in high-ish temps, the M117 has always run cooler. In the hottest 95F with 80+% humidity Texas heat, the most I would typically see my SEC run was 105C at high speeds with the A/C on. In this same scenario, the E500 would (or could) be in the 110C range.
  8. Note that even 120C is not going to kill an engine right away, as long as it is not overheated and run beyond this point. Think about the physics of the cooling system: a) the boiling point of water is raised when it is mixed with coolant. This is one prime reason why coolant is used (in addition to its anti-freeze properties); b) The pressure in the cooling system significantly raises the boiling point of the coolant -- this is why coolant does not boil over in MBs when things hit 120C

The bottom line to all of this is that:

  • Yes, it's probably best to have our engines running in the 85-100C range as a matter of daily course.
  • There are variances (mechanical systems' condition, designed-in tolerances, and conditional based on individual vehicles, and type of engine) that cause different cars to run at different temperatures.
  • It's unlikely that you have a cracked head or bad head gasket in an M119 engine, unless the engine was seriously abused in the past and overheated majorly.
  • ANY M119 can be run all day, every day at 100-105C with zero ill effects. This is in effect well within MB's established operating temperature range. Remember that the pressure in the cooling system raises the boiling point of the coolant well beyond the 115C range.
  • If your cooling system temps are going up and down, and keeping things within established temp range, that means that your cooling system is doing its job.
Cheers,
Gerry
 
Re: Head gasket, Yay or Nay?

Need to carve off the post Honch and place a copy with the heading "Is my car cooling?". Plenty of code words to find it easily when searched under the appropriate forum heading in all of the chassis types you mentioned.
 
Re: Head gasket, Yay or Nay?

Need to carve off the post Honch and place a copy with the heading "Is my car cooling?". Plenty of code words to find it easily when searched under the appropriate forum heading in all of the chassis types you mentioned.

People stress out hard when their car hits 100C.

People wig out majorly when the gauge hits 105C.

At 110C, many folks are in “OMG my car is dying and I’m overheating it!” Mode.

At 115C, folks are believing they have done permanent damage to their engine and head gasket, and the car will never run correctly again.

At 120C, people believe their engine is totally blown, and should be replaced.

None of this is true. Don’t believe the hype. 100C+ is just fine and nothing to wig about, particularly if you are in a hot and humid climate.
 
Re: Head gasket, Yay or Nay?

Absolutely agree with it being perfectly normal for motors to run hotter under certain ambient and conditions. Especially a long hill climb on a hot day will almost certainly send the needle close to the top of the range. As long is it comes down to "mid range" after the condition, in this case the hill climb, is over then all is good. I have too experienced this "OMG my car is overheating" paranoia from others, quite funny actually:agree:
 
Re: Head gasket, Yay or Nay?

on my car it stays pretty steady unless I don't use the a/c. The a/c system has a refrigerant pressure switch which activates the low speed fan relay.
 
Re: Head gasket, Yay or Nay?

For the OP, if you still think it's a head gasket/cracked head, and you want to try a sealant, the head gasket on my 1995 E420 was damaged back in 2014 while trouble-shooting clogged catalytic converters during a high RPM run and a major backfire. The symptoms were coolant loss and smell of antifreeze in the exhaust (https://youtu.be/tpwV_fx9kjY), though there didn't seem to be any oil in the coolant (I didn't do the strip test for this, so I'm not 100% positive there wasn't oil in the coolant).

Anyway, one bottle of this Bar's lasted a few years. I had to add a second bottle back in 2016 due to a slight but noticeable coolant loss. As a precaution, I changed the radiator prior to adding a second bottle. The old radiator did show some evidence of the silver fiberglass particles (sludge) collecting at the bottom and it probably did interfere with the cooling capacity to some degree because after changing the radiator, the engine seemed to run cooler. It has been doing fine since then.

So, if all your fans are working properly, as discussed by others, and you still think it's a head gasket, this is a cheap alternative and it has proven to work for me over the past 4+ years.
 

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Re: Head gasket, Yay or Nay?

People stress out hard when their car hits 100C.

People wig out majorly when the gauge hits 105C.

At 110C, many folks are in “OMG my car is dying and I’m overheating it!” Mode.

At 115C, folks are believing they have done permanent damage to their engine and head gasket, and the car will never run correctly again.

At 120C, people believe their engine is totally blown, and should be replaced.

None of this is true. Don’t believe the hype. 100C+ is just fine and nothing to wig about, particularly if you are in a hot and humid climate.

The last long trip I made was from Atlanta to Detroit. It was 92 degrees + and wickedly humid. With the A/C running the temp gauge was at 115+ until mid Tennessee when it began to drop to 110/105. I was a bit concerned however the red caution area of the gauge begins at 120. I believe in the engineers. I also run the engine up to the redline on many occasions. I'm pretty sure no one here thinks I'm advocating to ignore cooling issues. This was a singular occurrence due to extreme conditions.

drew
 
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Re: Head gasket, Yay or Nay?

I also run the engine up to the redline on many occasions.

drew
you are really asking for a premature death to your 119s by doing this, Drew!!

I know a fellow in Europe who used to own an .036 (Limited), and he never revved it about 3,500 RPM. True story!! I’m sure it will last eons, never being revved like that.

:stickpoke:
 
Re: Head gasket, Yay or Nay?

For the OP, if you still think it's a head gasket/cracked head, and you want to try a sealant, the head gasket on my 1995 E420 was damaged back in 2014 while trouble-shooting clogged catalytic converters during a high RPM run and a major backfire. The symptoms were coolant loss and smell of antifreeze in the exhaust (https://youtu.be/tpwV_fx9kjY), though there didn't seem to be any oil in the coolant (I didn't do the strip test for this, so I'm not 100% positive there wasn't oil in the coolant). ... Anyway, one bottle of this Bar's lasted a few years.
In this situation, with coolant loss & noticeable odor from the exhaust - I'd recommend the same treatment, until you're ready to dive into head gasket replacement (neither fun nor cheap).



I know a fellow in Europe who used to own an .036 (Limited), and he never revved it about 3,500 RPM. True story!!
While I would hope this is unhinged trolling... never running the engine hard can actually CAUSE problems. Assuming a motor is in good condition with proper fluids / maintenance, occasionally running it hard is actually a GOOD thing. Full throttle to the redline through as many gears as may be legal where you live, at least once per tank of fuel, is just what the doctor (Booth) ordered.


Back to the OP's issue, I really think it's a deader-than-usual fan clutch. Scientific diagnosis would require using an optical tach to measure fan blade RPM at idle, at full operating temp.

:v8:
 
Re: Head gasket, Yay or Nay?

I've re-read this thread: https://www.500eboard.com/forums/showthread.php?t=1391&page=5


To be more precise, I'm not concerned that my car is overheating, I know that happens after 120C

After 4.5 years of ownership and 13k miles and 100s of hours of forums I can't definitively settle in my head whether there is an issue or not. I'm a pedantic type and my car is not a beater. I understand the temp gauge is not an idiot type and it should be alive. Remember, mine is 1993 400E.

Here is what I have on hand that I can't reconcile:

1. fan clutch, by design, may not be engaged with coolant temp of 105C if ambient is 60-70F, yet there is a good portion of people that most of the time, irrespective of traffic conditions seat at coolant 85-90C. Meaning they are at this temp with out the fan clutch?
2. fan clutch suppose to kick in around 90-95C with >80F ambient, which implies 95C-100C is coolants supposed average temp and many people report that that's what they see on average

How do you reconcile 1 and 2? Can't be due to variations in tolerances.

3. If even in low ambient temp of say 50-60F, although it takes longer from initial engine starts, I still eventually get to 98C-82C cycle in DENSE traffic (have cool harness mode), then my issue is not fan clutch, because it's not suppose to come on in such low ambient temp?


What am I missing? Can't even do the roar test because it's 60F or below in northern VA right now.


P.S. GSXR, I've ordered ACM clutch (from FCP, per your link) and MB bolt for it. And thank you everyone for sharing your thoughts. I read everything
 
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Re: Head gasket, Yay or Nay?

How do you reconcile 1 and 2? Can't be due to variations in tolerances.

That’s exactly what it is. Its been discussed many times on this forum, and many times in this specific thread. No two fan clutches are the same. The variation in their cut in temperatures from the factory CAN cause the discrepancies you note.

I was in the same boat as you (minus the head gasket suspicions) after I purchased my e420. It took a bit to get used to the fact that the gauge moves around when driving, but as has been noted above, it’s nothing to worry about until you have sustained operation at 115C or higher across a wide variation of ambient temperatures. Even then there is probably some room to squabble.

You sound like you need to be convinced nothing is wrong, but it doesn’t look like any of the evidence and sound reasoning given thus far is doing the trick. Not sure what anyone is going to be able to add at this point to walk you back from the ledge. Perhaps just take the plunge and find out for yourself? Make sure to report back if you do!


Sent from my iPhone using Tapatalk
 
Re: Head gasket, Yay or Nay?

Not trolling. This was an E60 Limited AMG, now sold to another owner.

Not turning an E60 over 3,500 RPMs is “Blasphemy”. Why bother to spend the BIG BUCKS if you don’t intend to exercise it.

The PO should buy a Prius after selling the E60?

lol
 
Re: Head gasket, Yay or Nay?

Here is what I have on hand that I can't reconcile:

1. fan clutch, by design, may not be engaged with coolant temp of 105C if ambient is 60-70F, yet there is a good portion of people that most of the time, irrespective of traffic conditions seat at coolant 85-90C. Meaning they are at this temp with out the fan clutch?
What you may be missing is the fan clutch is an analog device. It's not binary, either on or off. The engagement amount, and fan RPM, varies infinitely. In general, the fan clutch SHOULD be (mostly) engaged at 105C, unless either ambient temps are abnormally low, OR if airflow is blocked directly ahead of the fan clutch face. This document, referenced in other threads, shows the FSM mention of the high engine temps in low ambients - read the "Caution" note at the end of page 5. Yes that is the M117 FSM and clutch, but the design is nearly identical.



2. fan clutch suppose to kick in around 90-95C with >80F ambient, which implies 95C-100C is coolants supposed average temp and many people report that that's what they see on average

How do you reconcile 1 and 2? Can't be due to variations in tolerances.
This document helps explain it somewhat. Assuming no airflow issues, and proper calibration, the clutch will generally be (mostly) engaged by 95C coolant temp with warm ambients.



3. If even in low ambient temp of say 50-60F, although it takes longer from initial engine starts, I still eventually get to 98C-82C cycle in DENSE traffic (have cool harness mode), then my issue is not fan clutch, because it's not suppose to come on in such low ambient temp?
The electric fans are not suppose to turn on until 107C. You are changing the factory design with the CoolHarness that turns the electric fans on ~10° early, and this is why you are seeing the 98-82-98 cycle. As mentioned previously in this thread, that indicates a lack of airflow... I think your clutch is not calibrated properly.



What am I missing? Can't even do the roar test because it's 60F or below in northern VA right now.
Klink mentioned somewhere (forget if it's on the forum) that the roar test can be performed in cooler ambients by revving the engine to ~3500rpm in Park with AC off, and after quite a while (15-20 mins?) the temp should get up to 100C+ at which point the clutch SHOULD engage and roar, if it's calibrated properly, AND there is no airflow blockage ahead of the fan, AND there is not a cold spot in the radiator ahead of the fan. Remember - the fan engages based on AIR temp. Not coolant temp!!
Disclaimer: I've never attempted what Klink described. I do all my clutch testing in summer with 90F+ ambients, because it's easier.



P.S. GSXR, I've ordered ACM clutch (from FCP, per your link) and MB bolt for it. And thank you everyone for sharing your thoughts. I read everything
I'll almost guarantee the ACM clutch will stop your coolant temp fluctuation, to the point where you could remove your CoolHarness or even disconnect the electric fans (temporarily) as a test. I'm really curious what happens when you install it.

:pc1:
 
Re: Head gasket, Yay or Nay?

That’s exactly what it is. Its been discussed many times on this forum, and many times in this specific thread. No two fan clutches are the same. The variation in their cut in temperatures from the factory CAN cause the discrepancies you note.

I was in the same boat as you (minus the head gasket suspicions) after I purchased my e420. It took a bit to get used to the fact that the gauge moves around when driving, but as has been noted above, it’s nothing to worry about until you have sustained operation at 115C or higher across a wide variation of ambient temperatures. Even then there is probably some room to squabble.

You sound like you need to be convinced nothing is wrong, but it doesn’t look like any of the evidence and sound reasoning given thus far is doing the trick. Not sure what anyone is going to be able to add at this point to walk you back from the ledge. Perhaps just take the plunge and find out for yourself? Make sure to report back if you do!


Sent from my iPhone using Tapatalk


Sorry this doesn't come across as humble: I'm a [very] high-resolution individual. I must collect abnormally high, by the average person's standards, cross-references before I settle on conclusion. Even then it's still a "running" conclusion. I don't reject or block out any suggestions brought forth by the collective here. Neither am I looking for lost keys under the street light, even though I lost them in the dark alley - you understand what I mean. I'm collecting them and cross-referencing trying to arrive to a-to-me satisfactory understanding. Everyone's patience is appreciated. If you're annoyed - I understand that too :-)
 
Re: Head gasket, Yay or Nay?

By the way, I have found that running temperatures are EXTREMELY dependent on ambient temperatures, as well as humidity levels.

However, in fall and winter, I am finding the car runs nice and cool -- in the 85-92C range. There's no way I can get the car anywhere near 100C in winter (30s and 40s temps) even if sitting idling for 5-10 minutes, or driving the Dulles Airport Toll Road at 90-95 MPH because I'm late for a flight).

Cheers,
Gerry

Gerry, if ambient temps are 30s and 40s and you'd idle for 30-40 minutes, what would the highest coolant temp your car achieve? Thanks
 
Re: Head gasket, Yay or Nay?

Sorry this doesn't come across as humble: I'm a [very] high-resolution individual. I must collect abnormally high, by the average person's standards, cross-references before I settle on conclusion. Even then it's still a "running" conclusion. I don't reject or block out any suggestions brought forth by the collective here. Neither am I looking for lost keys under the street light, even though I lost them in the dark alley - you understand what I mean. I'm collecting them and cross-referencing trying to arrive to a-to-me satisfactory understanding. Everyone's patience is appreciated. If you're annoyed - I understand that too :-)

Not annoyed! I just don't think there is any additional info to add that hasn't already been shared. :)
 
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Re: Head gasket, Yay or Nay?

Not annoyed! I just don't think there is any additional info to add that hasn't already been shared. :)

well, if ambient temps are 30s and 40s and you'd idle for 30-40 minutes, what would the highest coolant temp your car achieve? I'm also curious how gerryvz would answer this question. That'd be additional information
 
Re: Head gasket, Yay or Nay?

Gerry, if ambient temps are 30s and 40s and you'd idle for 30-40 minutes, what would the highest coolant temp your car achieve? Thanks

I could see my car with a long idle getting up to the 90-95 mark with a long idle.

Just today I idled for 15 minutes in a parking lot after a high speed 35 mile drive, in 47F temps, and I never cracked the 90-92C mark.

Here is my car today, driving at ~80MPH on the freeway. You can see the ambient and the temp gauge.

If this was summer and 90F ambient & high humidity, driving at 80+ MPH, that indicated temp would be 105+C.

Cheers,
Gerry

proxy.php
 
Re: Head gasket, Yay or Nay?

I could see my car with a long idle getting up to the 90-95 mark with a long idle.

Thank you. For the above, do you think there'd be any clutch engagement or would 90-95 mark be capped just by water pump? (we're still assuming low ambient temperature) Am I correct in my understanding, that you suspect currently installed clutch in your car may not be performing to 100% proper standard?
 
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Re: Head gasket, Yay or Nay?

Thank you. For the above, do you think there'd be any clutch engagement or would 90-95 mark be capped just by water pump? (we're still assuming low ambient temperature) Am I correct in my understanding, that you suspect currently installed clutch in your car may not be performing to 100% proper standard?
By the way, in summer heat/humidity, with A/C on, the temp after a long (15 min) idle would definitely be at the 105-110 mark, perhaps higher. However, my secondary fan would kick in as needed, and reduce temp down to around 90-95C, and then it would climb again and the cycle would repeat.

For the photo above, I DID NOT have the A/C running. Temp would automatically have been 5C higher with A/C running.

By the way, trust me, my car spends A LOT of time well over the 100C mark when it's summer time. 10 years in Texas summers, and summer here in Maryland as well. I almost think that humidity plays a larger role than just raw ambient temp does.

For example, per my photo posted above. If it was 51F ambient temp, but high (summer) humidity, I believe that the temp would be much closer to 100C at that high 80MPH driving speed.
 
Re: Head gasket, Yay or Nay?

Thank you. For the above, do you think there'd be any clutch engagement or would 90-95 mark be capped just by water pump? (we're still assuming low ambient temperature) Am I correct in my understanding, that you suspect currently installed clutch in your car may not be performing to 100% proper standard?
At idle, temps would be handled by the first-stage of the electric fan (if the A/C was on), and at 105+ coolant temp, the second stage of the electric fan would kick in and rapidly lower the temp. A properly working fan's second-stage is pretty effective at mitigating temps. I don't think the fan clutch would do anything at idle. Also at higher speeds, the fan clutch dis-engages and the cooling relies on airflow through the radiator at the high velocity the car is traveling, as well as the first-stage (if A/C is running) of the electric fan (and possibly the second stage of the electric fan if the coolant temp is high).

Remember that clutch engagement is conditional -- it doesn't happen at all RPMs and the clutch is designed to cut in and out at certain RPM levels, as well as sensed ambient temps (which engage or disengage the bi-metallic strip).
 
Re: Head gasket, Yay or Nay?

At idle, temps would be handled by the first-stage of the electric fan (if the A/C was on), and at 105+ coolant temp, the second stage of the electric fan would kick in and rapidly lower the temp. A properly working fan's second-stage is pretty effective at mitigating temps. I don't think the fan clutch would do anything at idle.

I just did a test. Ambient temp 54F, humidity 88%. Idling outside, A/C off, from cold start to 98C: 23 minutes. About 40 seconds for aux fans to bring it down to 82C. If not for cool harness mode, I'm convinced coolant temp would have risen to 105C, where with out cool harness mode, aux fans would bring it down to 82C in about a 1-1.5 minutes. I know for sure that had it been 30F outside, it would take several minutes longer to reach 98C

If I'd remain idling, 98C-82C cycle would happen about every 2-3 minutes

My issue then, is not fan clutch, right? Or does it seem "within the limits of tolerance" to you?
 
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I'm still putting my $$$ on the fan clutch. Airflow from electric fans drops the temperature. If the mechanical fan was spinning faster, it would do the same thing. You can't tell what the mechanical fan is doing without using an optical tachometer to measure RPM of the fan blade. I think I posted data on fan blade speed measurements in one of the old/long threads on fan clutches. The clutch really does something at idle when engaged... but again, it has to be at least partly engaged. The ACM clutch is engaged far more than OE which is why I think you'll see a difference with it installed.

Put another way, given your cold-start-timing-test... if the mechanical clutch was moving more air, your car may have never reached 98C in the same conditions.

The docs linked previously have more data on the fan specs, but the OE clutch disengages at 3500rpm. That's 90+mph in an E500E, and felonious speed in a 400E420 with 2.24 gears. There is some ram-air effect at freeway speeds, but it's not adequate to keep the engine fully cool in high ambient/summer temps. Which is why the fan is there.

Oh, and make sure your rubber flappies are present on the fan shroud. These are designed to open at freeway speeds with the clutch disengaged, so air can flow through the shroud. But when the clutch is engaged and fan roaring, it pulls the flaps closed so the fan is pulling air through the radiator core; and not pulling engine compartment air through a hole where a rubber flap broke off.

:roadrunner:
 
GSXR, I can't say I'm not extra happy and hopeful to hear your such response! Will report back. Thanks for all of your links and explanations - I read everything.

I checked, all flappies are there. Shroud was replaced with new part in December of 2014
 
Fan clutch it is! After 4.5 years, PROBLEM SOLVED! What a beautiful roar ACM clutch makes!



  • ACM clutch replaced original Mercedes part made by Fichtel & Sachs, that was put in brand new and was exactly 4 years (Dec 2014) / 7k miles old (as of 2.14.19). Which itself replaced MB clutch that was, maybe original, from 1993(?)
  • In comparison to ACM clutch, I think I've never heard Fichtel & Sachs engage, either new for-for-2014 or the original-from-1993
  • ACM is heard EVRY TIME even at idle, at ambient 46F - pleasant (to me), quiet-but-pronounced hum of a brand new house A/C condenser - listened from outside the car; can't hear inside.
  • Pleasant roar from stop until 3,500 RPM (peak noise), then quiets down right away and cuts out at 4,000-4,500 RPM (engine).
  • From 2,000 RPM to 3,500 RPM feels like 15% throttle to full in a span of milliseconds on an airplane turbofan engine (obviously not as loud) then back to 15% from 3,500 RPM to 4,500 RPM (engine)
  • Instead of 98C-82C every 2 minutes in moderate traffic with stop lights, now my car is 82C-85C!!!
  • ACM fan clutch operation is significantly noticeably-audible inside the car from 2,000-3,500 RPM (engine). Unusual by modern standards, but not terrible (kinda like jetliner from stop to full for 1 second, but much quieter of course; though similar sensation).
  • Tested for 1 hour idling in ambient 46F, 52% humidity - remained at 82C. Previously, at 58F, 88% humidity would reach 98C in 23 min and cycle 98C-82C every two minutes with the help of aux fans, and in moderate traffic for 25 miles


  • quick reminder: previously replaced 4years/7k miles ago or less: radiator, water pump, coolant, ceramic resistor behind left front headlight - with no effect.


Old clutch (brand new Dec 2014, since then 7k miles on it). Never heard it engage (it might have, just never heard it vs what I hear with ACM, which is so obvious/pronounced and pleasant)

IMG_20190214_235737.jpgIMG_20190214_235745.jpgIMG_20190214_235804.jpgIMG_20190214_235829.jpg


GSXR - thanks!!!!!!!!!!!! :gsxrock:. With out You, I'd still be in doubt if it was a fan clutch issue [respond to my PM!!!!! :-) ] About 6-7 Mercedes indies in CA and VA told me about 98C-92C: "it's ok", "it's supposed to be like that", "that's fine", "don't worry about it just drive it", "you worry too much" etc. I assume you are correct that a properly working MB clutch should work (to some extent) even at idle, even at relatively low ambient temperature! (46F). That even Gerry (:bowdown:) assumed fan clutch does not apply to idle is humbling. I wonder if there are things Klink could stil learn and be surprised about with M119 engine? :detective:

It's a little sentimental that aside from 20-30-maybe 40K(?) people on this planet, no one knows/cares about M119. We are hermits and a rapidly aging/dieing off breed :-)



P.S. our cars, at the end of the day, don't need a proper working fan clutch? mine survived SoCal for 4 years on aux fans :jono:
P.S.S. Is the MB fan clutch in the picks with only 4 years/7k miles a throw-away? r can it be sold for rebuild?
 
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Does the low speed fan on your radiator fan come on with the a/c running?

Keep an eye on that FC. I thought the newer run of ACM clutches was from asia.
 
Fan clutch it is! After 4.5 years, PROBLEM SOLVED! What a beautiful roar ACM clutch makes!
YES! Congrats! Once you hear the fan roar, it all makes sense, eh? :D


Old clutch (brand new Dec 2014, since then 7k miles on it). Never heard it engage (it might have, just never heard it vs what I hear with ACM, which is so obvious/pronounced and pleasant)

So.... I'm confused here. The old clutch is date coded 1993 and looks like it has waaaay more than 4 years / 7kmi on it. Any new clutch from Dec-2014 sourced through an MB dealer would be branded Horton (they bought out F-S), and would have a date code 2010+. Assuming an indy shop replaced it, my speculation is they sourced a used clutch from somewhere and likely charged you for a new one ($$$), or worse yet they didn't change anything at all if they believed nothing was wrong. :scratchchin:



P.S. our cars, at the end of the day, don't need a proper working fan clutch? mine survived SoCal for 4 years on aux fans :jono:
If the high-speed fan circuit is working, it will keep engine temps out of the danger zone... which is kind of the purpose of the electric fans (along with helping AC performance on low speed). But as you found, the engine temps will be higher than they otherwise would be with adequate airflow.



P.S.S. Is the MB fan clutch in the picks with only 4 years/7k miles a throw-away? r can it be sold for rebuild?
Check with Jono, he may be interested. There is nothing to rebuild, but assuming the center bearing is good, they can usually be re-calibrated as mentioned earlier in the thread.



Keep an eye on that FC. I thought the newer run of ACM clutches was from asia.
I think they are likely made in Asia somewhere. Nobody knows, as the packages and clutch have no COO marked. Pretty much the only thing we have to go on is that nobody has reported catastrophic failure of an ACM clutch (yet), and they disengage ~4500rpm which is better than some other units on the market. Of more concern is the ACM clutch doesn't appear available at some vendors, making me wonder if it could end up NLA.


:tigger:
 
Does the low speed fan on your radiator fan come on with the a/c running?

Keep an eye on that FC. I thought the newer run of ACM clutches was from asia.

Yes, aux fans kick in at low speed with A/C on. ACM is stamped with "China". I'm not too concerned with stuff made in China if the brand is proper. After all, Iphones are made in China too. When it's an unknown brand and it's made in China, I get suspicious
 

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