Ticking, and worn cam bushings at 60k Km?

[andresyver]

Hello M119'ers...

Background:

About 400 kilometers ago I noticed a ticking noise from the passenger side bank of cylinders. Perusal of this board led me to suspect cam oiler tube failure. Board member Justin sent me a set of cleaned and O-ringed tubes. Following board admin Gerry's excellent how-to, I replaced the plastic oiler tubes with the aluminum set. It was a good time to replace the 20 year old upper harness, which showed its age (cracked brown ground wire that attached to harness strap mounting point on intake manifold).
A loose hex bolt on the cam cover (yes, the hard to reach rearmost one) indicated a previous intervention. I've had the car for 20k Km, so why would anyone have been in there before 40k Km?
When I removed the last two (rear) plain (as opposed to the grooved rearmost) caps on the exhaust cam, I smelled burnt oil and noticed uneven wear on the caps. All other caps looked like new.
All the plastic oiler tubes and O-rings were in perfect shape.

The last 50km I drove I noticed a higher than normal oil temperature (100 instead of 80) together with a lower than normal pressure at idle.
I've always used synthetic oil, and the previous owner claimed same.

Questions:
1) Is there an oil gallery that feeds this area of the cams and the corresponding lifter? I'm suspecting the ticking to be due to that lifter not receiving oil pressure.
2) If so, is there some way to blow air into the gallery to try dislodging any blockage?
3) Could these symptoms be caused by anything else?

TIA,
Andres

 

[samiam44]

What year is your car?


Does the engine show oil pressure >0.5 bars on the dash cluster? I would not drive it in this condition. If you have low oil pressure with the correct weight oil, you should pull the lower oil pan and clean/replace the oil screen and grommet.



Michael

 

[gsxr]

It does sound like this may affect only a particular cam bearing cap, which may be a blocked passage internally. However I'm not sure how to either diagnose or fix the problem. Very, very strange.

 

[andresyver]

What year is your car?


Does the engine show oil pressure >0.5 bars on the dash cluster? I would not drive it in this condition. If you have low oil pressure with the correct weight oil, you should pull the lower oil pan and clean/replace the oil screen and grommet.



Michael

Hi Michael,
Thanks for the reply!
By low oil pressure I mean around 1 bar at hot idle. Before this event, it used to be close to 1.5 bar at hot idle. Over 1000 rpm it would always (and still does) peg the gauge. I've not started the engine after discovering the oil feed problem.
Andres

 

[andresyver]

It does sound like this may affect only a particular cam bearing cap, which may be a blocked passage internally. However I'm not sure how to either diagnose or fix the problem. Very, very strange.

Hi GSXR, thanks for the reply...
Its only two cam bearing caps on the passenger side exhaust cam. I imagine that if I remove the cam, the oil gallery to those bearings should be visible... I'm afraid to blow compressed air in, since it won't (AFIAK) be able to get past the oil pump...
andres

 

[gsxr]

Hi GSXR, thanks for the reply...
Its only two cam bearing caps on the passenger side exhaust cam. I imagine that if I remove the cam, the oil gallery to those bearings should be visible... I'm afraid to blow compressed air in, since it won't (AFIAK) be able to get past the oil pump...

I agree - don't blow compressed air in a direction where there's not a clear exit. Don't want to move the problem to a different location.

Any chance you could post some photos of the bearing caps with uneven wear?

 

[DerFuror]

A loose hex bolt on the cam cover (yes, the hard to reach rearmost one) indicated a previous intervention. I've had the car for 20k Km, so why would anyone have been in there before 40k Km?

It could be possible that an uninformed mechanic/technician previously removed the cover to replace at least 2 failed plastic oiler tubes with new plastic tubes, failed to properly identify the caps upon removal & then mismatched the caps upon re-installation (thereby causing uneven wear) and/or failed to re-torque the caps to specification.

...and by not having the proper tool for the job, the technician was unable to securely fasten the rear cover bolt.

As mentioned, it is probably a good idea to remove the lower oil pan & inspect for debris contamination. This may provide evidence supporting the theory of oil passageway blockage.

I will be replacing my car's oiler tubes during this off-season because of a ticking on the rear driverside. Compressed air is a method used to dislodge blockage, however I am not yet familiar with the M119 cam oil delivery design & the ability/ease of addressing a potential blockage with compressed air, or the ability to observe the cam oil delivery with the cover off.

 

[J-Sauce]

Andres, what year is your car? When my car developed a ticking noise it was due to worn and disintegrated chain rail pieces clogging the oil pickup. Later engines received an updated pickup nozzle which would help alleviate the problem of debris becoming stuck permanently against the oil pump screen. However, if there is enough debris in your oil pan, it will not make a difference. My next action, as suggested above, would be to drop your lower oil pan and check for debris clogging the oil filter. If your cam covers are still off, visually inspect your chain rails from above. Maybe gxsr can help with some photos.

Justin

 

[andresyver]

I agree - don't blow compressed air in a direction where there's not a clear exit. Don't want to move the problem to a different location.

Any chance you could post some photos of the bearing caps with uneven wear?

Hi GSXR,
I will be back onsite tomorrow morning, will remove caps again and post photos.
thanks,
Andres

 

[samiam44]

I'm sure the oil pump is removable with the engine in the car.

I would think(without looking), that removal of the oil filter housing would allow blowing out the oil gallery. Food for thought, this is a Euro car- maybe someone broke the engine oil cooler and ran it low on oil or replaced the oil cooler or line and got a bit of trash in the system.

I would take the mixed up cap idea for middle ones. The rear cap is not interchangeable.

Someone could have removed all the cam bearing caps at once and bent the camshafts or distorted the last cap which was loaded by a spring possibly. FSM is specific to only remove the caps one at a time or set engine at 45 degrees and ??loosen them gradually.

Could have been a little debris on assembly of the cap too. Honestly, this is above my desktop skill level. I'd have to be there to give a better opinion.

Michael

 

[andresyver]

Andres, what year is your car? When my car developed a ticking noise it was due to worn and disintegrated chain rail pieces clogging the oil pickup. Later engines received an updated pickup nozzle which would help alleviate the problem of debris becoming stuck permanently against the oil pump screen. However, if there is enough debris in your oil pan, it will not make a difference. My next action, as suggested above, would be to drop your lower oil pan and check for debris clogging the oil filter. If your cam covers are still off, visually inspect your chain rails from above. Maybe gxsr can help with some photos.

Justin

Hi J-Sauce,
the car is a 1994 E420.
when I removed the upper chain guide on that bank it looked intact. I did, however break a couple of the tabs that hold the two parts together. A silly, cheap design. I peered down the sides of the chain, and the lower guides looked ok, but it's hard to see. Next step, remove pan. I've not thought a clogged pickup could be a problem, since I've got good pressure an normal rpms.
thanks,
Andres

 

[andresyver]

I'm sure the oil pump is removable with the engine in the car.

I would think(without looking), that removal of the oil filter housing would allow blowing out the oil gallery. Food for thought, this is a Euro car- maybe someone broke the engine oil cooler and ran it low on oil or replaced the oil cooler or line and got a bit of trash in the system.

I would take the mixed up cap idea for middle ones. The rear cap is not interchangeable.

Someone could have removed all the cam bearing caps at once and bent the camshafts or distorted the last cap which was loaded by a spring possibly. FSM is specific to only remove the caps one at a time or set engine at 45 degrees and ??loosen them gradually.

Could have been a little debris on assembly of the cap too. Honestly, this is above my desktop skill level. I'd have to be there to give a better opinion.

Michael

hi Samiam44,

How would I go about checking correct cap sequence? It is middle caps that are wonky. Could I just purchase two new caps to replace worn ones? It seems that cam removal is in order...
as suggested, will check for debris in pan, remove oil filter housing, remove cam, blow out passageways, reassemble.
It will take a while, need to order some parts from USA. Local dealer is frightening me with parts prices.
Thanks,
Andres

 

[gsxr]

when I removed the upper chain guide on that bank it looked intact. I did, however break a couple of the tabs that hold the two parts together. A silly, cheap design.

If any of the tabs broke when you removed the upper guide (between sprockets)... they were probably brittle from age + heat, despite the low kms/miles. Replace both sides, these pieces are cheap. Click here for what you do NOT want to see for the inner guides.

How would I go about checking correct cap sequence? It is middle caps that are wonky. Could I just purchase two new caps to replace worn ones? It seems that cam removal is in order.

I believe the caps should be numbered, stamped into the cap itself. Check to see if they are all in order. You can't just buy new ones... they are machined to the head, i.e. new caps are all installed and then it's line-bored at the machine shop. It isn't likely the caps were mixed up, but might as well check while you're in there.

 

[samiam44]

Start w have a suggestion. These are aligned by hollow alignment pins. Make sure they are there.

Clean bearing cap, and matting part of head. Look for witness marks, make sure the cap is not bent with a machinist straight edge.

I do believe if the two caps were reversed, you can probably put them back, run a high zero oil and it should seat.

I'm worried a bit as I would not expect a change in oil pressure.

Look at lifters in this area. Any scuffing and it needs to be replaced. Any marks on the cam lobs and it gets replaced.


Blow out the new oil tubes and make sure they are clean. I think the ina lift is common to vw/Porsche


Start w earliest first. Clean pan and inspect cam bearing caps.

M

If the head is damaged, used ones are cheap. Get it rebuit and install. But that is a big mechanical job. Let's hope it is simple.

 

[samiam44]

If you pull the pan. There are orings on the oil level sensor. Replace them.

You might try mb Gainesville or classic mb parts in California. Both will get you the best prices possible.

Jono and David hendy have parted out a couple 420s. Might have a head if you need one.

Try to help all that I can. Email or pm.

 

[samiam44]

When I look for witness marks. Signs of damage to the machined surfaces. Maybe they got a cap cocked and it generated a bur. Or they seperated on w a chisel or screw driver. Do good detective work.

Caps I think are stamped. Mb is a single plane crankshaft design. Din ?72074.

M

 

[andresyver]

Hi All,
Back at the car, checked the cam blocks for correct order, they all matched the numbers stamped on the head. No signs of damage or prying on mating surfaces.
Photographed the wear on cam block bearing and cam, but don't know how to post to this forum from IPhone. Drained oil, which smelled like overheated engine, pulled oil pan, half a cup of oil nicely sloshed down my collar AFTER I thought pan was drained, checked pan, no residue of any kind, oil strainer at pickup was clean. Cable wrap that was zip tied to rear lip of pan disintegrated when touched.

What could be causing damage to cam and ticking lifter?
Oil pressure was fine over 1000 rpm, when idling at 500 it dropped to around one bar when hot, but only in last 50km or so of use. Same with higher than normal water temp-100 instead of 80C.
any suggestions as to where to blow from to see if there is anything blocking oil gallery?
Filter canister is out.
Unless anyone suggests otherwise, next step is pulling that right bank exhaust cam.
ive read the FSM and GSXR's write-up, but still don't understand how to slip chain up over that cam sprocket, unless those few degrees to turn each cam after finding 45 BTDC is enough to loosen the chain.
Suggestions?
TIA,
Andres

 

[samiam44]

I'm not convinced there is anything in the oil galleries. I am assuming you are using a recent OEM or OE quality oil filter? I have seen oil filters which were 2-3 years old get soft(paper) and discharge into the oil pipes. I replaced an engine in a W108 which died that death. New short block and rebuilt the heads.

To answer your question on ticking- those lifers are picky.

M

 

[gsxr]

... but still don't understand how to slip chain up over that cam sprocket, unless those few degrees to turn each cam after finding 45 BTDC is enough to loosen the chain.

Wait a sec... remind me why are you are trying to get the chain off the cam sprocket?

If removing the cams, you have to remove the chain tensioner first, then remove at least one sprocket (maybe more) to allow enough chain slack to get the cams out. BIG, big job here. If going in that deep, I'd replace all the upper chain rails (particularly the two inside on the "V" part) while you have it apart.

 

[andresyver]

I'm not convinced there is anything in the oil galleries. I am assuming you are using a recent OEM or OE quality oil filter? I have seen oil filters which were 2-3 years old get soft(paper) and discharge into the oil pipes. I replaced an engine in a W108 which died that death. New short block and rebuilt the heads.

To answer your question on ticking- those lifers are picky.

M

I know, not very likely, except for the suggestion that someone replaced an oil cooler at some point, it's hard to imagine crud getting in there. I've used Knecht brand filter cartridges since I've had it, the PO did as well.
Picked up a few replacement MB lifters on eBay, I might change the set under that cam.
thanjs for the reply!
Andres

 

[andresyver]

Hi GSXR,
Id like to get the cam off for two reasons: First to measure it and see if it's to spec, since I think I see some scratches at the bearing surface (I wish I could post from my iPhone to the forum-would anyone be so kind as to receive a Pmail from me and then post to the thread)? Someone that knows more than I do could look at the photos and discern what's going on. I was on a road trip in another country when this happened, so no access to a computer, I'm literally doing this under a tree in a helpful soul's yard.
the second reason for pulling the cam is to see what might be going on with the oil feed to the cam and lifters.
thanks,
Andres

 

[andresyver]

The PO only drove it a couple of thousand kilometers a year, AND he is a notorious cheapskate, so it's likely that the filters sat for years between changes. As soon as I got it I changed EVERY fluid, and have continued proper maintenance since.
Remember, I've driven 20K high revving Km since, with no trouble until now.
Andres

 

[Allgonquin]

Hold on a minute. The first post talks about oil temp going from 80 to 100. Then post 17 talks about water temp doing the same. First post mistake? Anyway, high water temp presumably means higher engine temp which would cause lower oil pressure, similar to when the car warms up from cold. Anyway this does not help the ticking situation, but would explain the lower oil pressure when the engine is running hotter. So why is the engine running hotter?

 

[samiam44]

Awesome to hear your car is well maintained.


Good to hear your going the safe road and replacing offending lifters. FYI, I believe the INA lifters are common with other german 4V engines. VW/Porsche. Not sure on the advantage, but if you do a full set- DLP is popular with sliding flat lifters. If the VW ones will work they are ~$16 each.
I believe you can the new ones coated if you like-



Michael

 

[andresyver]

Hold on a minute. The first post talks about oil temp going from 80 to 100. Then post 17 talks about water temp doing the same. First post mistake? Anyway, high water temp presumably means higher engine temp which would cause lower oil pressure, similar to when the car warms up from cold. Anyway this does not help the ticking situation, but would explain the lower oil pressure when the engine is running hotter. So why is the engine running hotter?

Hi Allgonquin,
Thanks for the reply!
Yes, first post mistake, meant water temperature, no oil temp gauge on this car. My guess as to the higher operating temperatures is an oil feed problem, insufficient lubrication, higher friction, higher temp, observed wear on two cam blocks.
i found a place to safely store the car while we gather the gaskets and chain guides needed to dive deeper into the engine.
Still don't know why some cam blocks show wear and not others.
Andres

 

[andresyver]

Deleted duplicate post. Odd, second time this happens while attempting to reply to another post.

 

[andresyver]

Awesome to hear your car is well maintained.


Good to hear your going the safe road and replacing offending lifters. FYI, I believe the INA lifters are common with other german 4V engines. VW/Porsche. Not sure on the advantage, but if you do a full set- DLP is popular with sliding flat lifters. If the VW ones will work they are ~$16 each.
I believe you can the new ones coated if you like-



Michael

Hi Michael,
Thanks for the info on viable alternative lifter sources! I've got six on hand, enough for three cylinders on this offending cam. Was able to secure storage space for the car, will be home Friday and will post pics of the wear on cam block bearing surface. Will order gaskets and chain sliders in order to be able to dive deeper into the engine. Still completely clueless as to the underlying cause of this issue.
Thanks again to all of you for your support and to the site admins for providing such a valuable resource!
Andres

 

[andresyver]

Hi All,
Here are the photos of the wear on cam blocks and cam.
Is it bad? Looks bad...

TIA,
Andres

 

[andresyver]

Hi, Would anyone care to comment on the images?
Thanks,
Andres

 

[gsxr]

I don't like the wear visible on the cap or the cam, but I don't know what could be done to repair it without pulling the head. I'd be tempted to re-assemble and hope it does not get any worse.

The primary issue, IMO, is trying to prove if that particular cap is getting proper lubrication (oil flow). I'm not sure how you would test this.

 

[DerFuror]

Hi, Would anyone care to comment on the images?

The cap & cam bearing surfaces have been adversely affected (particularly, the scoring marks on the cap which I interpret as a combination of both insufficient lubrication & material deterioration/debris caused by lack of sufficient lubrication, but the metal surfaces are not overly discolored as a severe lack of lubrication would demonstrate). This may be the result of a partially blocked oil delivery passageway. Debris may have been moving through the passageway & finally reached a critical point in the passageway creating a restriction which caused this situation. You became aware & shut the car down before a possible major failure.

As samiam44 mentioned, I would be tempted to remove the oil filter housing, then insert a thin, strong wire into the cam oiler delivery hole & probe the oil passageway to its opposite end (also check the cam oiler tube), then probe a passageway of a known good oiler delivery hole for any noticeable differences. Assuming the passageway leads back to the oil filter, I would place a white paper towel at the oil filter end, then blow compressed air back through the cam oiler hole to observe what comes out of the hole against the paper towel. Hopefully a logical reason for this problem can be concluded with some tangible evidence.

I empathize your situation. I would make arrangements to transport the car home. I would not attempt driving unless it is proved that there was a blockage, the blockage is now cleared...and I had no other choice.

 

[maw1124]

Please pardon my ignorance here... But is there a bright line build date between metal and plastic oiler tubes?

maw

 

[gerryvz]

Please pardon my ignorance here... But is there a bright line build date between metal and plastic oiler tubes?

maw

GSXR has extensively researched that situation, and I think he's got it pinned down to the exact chassis number.

 

[gsxr]

No yank, Gerry, but good attempt.

maw, it appears there was overlap in production, more details here:
http://www.500eboard.com/forums/showthread.php?t=641

 

[maw1124]

I'll see if I can shed some additional light (or confusion) on the topic. Mine is a Jan '92 build, and I will try to see what it has. I'll post it open the other thread though, just to keep the thread jack to a minimum.

Cheers,

maw

 

[Klink]

Well, I don't have dates, but it appears that the plastic tubes were used in production starting with these engine numbers:
M119.970: 031254
M119.971: 015655
M119.972: 002823
M119.974: 007127
M119.975: 008750

 

[Klink]

Was your engine rear cover removed and reinstalled at any time in the known past? The only occasions in which I have seen oil starvation to a single cylinder head were the result of over application of silicone types of sealants to the main oil gallery passages in the engine rear cover. The sealant may not break away into the oil flow for many years and miles, so it is almost impossible to "timeline" and not likely to be considered.

 

[Klink]

Hi, Would anyone care to comment on the images?
Thanks,
Andres

As long as the cause is found and eliminated, I don't think the damage shown is enough to cause any problems in the future. Unless a cause is found using some of the methods described above, I don't think that you can be certain any cause is eliminated without complete engine disassembly and cleanup.

Also, don't forget that plugged piston cooling jets can result in piston deformation and engine destruction at autobahn speeds and /or mountain climbing loads. Sorry to add to your mental burden, but you have to consider this as well.

 

[samiam44]

Ok,

I don't see bluing. Maybe a bit of dirt, but it's odd that the lifters are at the offending oil tube. Yes, to warrantee something, Klink is right- you'd dissemble (peace of mind), go through the whole engine. Spend lots of time and $500 + in parts, end up with peace of mind. If I pulled that cam, I would probably polish it a bit to remove the ridges or lessen them. I would absolutely make sure everything went together clean- very clean. I did not ever suggest to root out the oiling system with metal wire to remove debris.

I see lots of specs of dirt/carbon/oil deposits.


Michael

 

[DerFuror]

I did not ever suggest to root out the oiling system with metal wire to remove debris

Correct. I did. You suggested oil filter housing removal in thread #10, which I credited you for prior to my mentioning about probing the oil passageway.

 

[samiam44]

Yep,

removal of the housing and blowing things out with compressed air, if you break stuff loose- you probably have bigger problems. Clean the housing and look for debris in the check valve. You can buy a box of lint free painter's rags from paint store. I isopropol alcohol from the aircraft maintenance supply (spruceaircraft.com if you have to order it).

Klinks suggestion is solid and would give 100% confidence. Let's see what the cam/lifters look like when you get them out.

Clean the whole area and housing prior to removal. Trying to keep junk out of the system.

Michael