RESTO PROJECT: M119 / W124 / E500 Engine Top-End Refresh

[emerydc8]

Thanks again to both of you guys. Hopefully the dealer figured out the EPC error and sent me the correct sensors. I will install them dry with a crush washer.

 

[emerydc8]

I just replaced the three coolant sensors on the intake manifold. Just a tip about accessing the 4-prong sensor when the intake manifold is on-vehicle: With the fuel rail and plug wire tray in the way, I had trouble getting a 22 mm open-end wrench on the sensor. My 22 mm deep socket would not fit over the sensor base due to the short distance between the base and intake manifold runner. I found that a CTA Tools 2064 Thin Wall Oxygen Sensor Socket worked very well for this. With the slot in the socket facing the manifold runner it allowed just enough room to unscrew the sensor, repositioning the socket when the socket wall touched the runner. Installation also worked well with this tool. 2064 - Oxygen Sensor Socket - Thin Wall - 7/8" (22mm)

 

[nocfn]

Crows foot works too IIRC.

 

[gerryvz]

That's a good tip. I also recall having slight difficulty accessing that sensor, due to its location, but was able to get it.

It helped a lot in my case that the manifold was out of the car, so I could get a much better bite/angle on it.

 

[emerydc8]

There's not a lot of room in there. I don't have a 22 mm crow's foot wrench. Larger sizes are on my list of things to get

 

[gerryvz]

I definitely would not have enjoyed doing that job with the manifold atop the engine, unless I was forced to due to a failure. You are brave.

 

[emerydc8]

I definitely would not have enjoyed doing that job with the manifold atop the engine, unless I was forced to due to a failure. You are brave.

That’s minor compared to all your work in this epic string!—and documenting it so meticulously! It should be required reading for all new MB techs.

 

[gerryvz]

I have been wondering if anyone will follow in my footsteps on this type of project. I know @Jlaa has been threatening to do something along these lines.....

I was very lucky to have done it exactly when I did, as numerous parts I replaced are NLA (such as the BERU distributor caps and such) in the past two years. I considered my engine to be well taken care of and still there was so much degraded rubber and parts in need of cleaning and replacement. It goes to show just how much deferred maintenance is lurking about under the hoods of so many folks' cars. Often, we don't know what we don't know, until we are forced to know.

This whole project for me basically started out as a front crankshaft seal replacement, because I was tired of having an increasingly drippy engine for probably the five to seven years before I did the job. COVID and its forced isolation was the perfect excuse to do the job.

 

[Ian White]

I have been wondering if anyone will follow in my footsteps on this type of project. I know @Jlaa has been threatening to do something along these lines.....

I was very lucky to have done it exactly when I did, as numerous parts I replaced are NLA (such as the BERU distributor caps and such) in the past two years. I considered my engine to be well taken care of and still there was so much degraded rubber and parts in need of cleaning and replacement. It goes to show just how much deferred maintenance is lurking about under the hoods of so many folks' cars. Often, we don't know what we don't know, until we are forced to know.

This whole project for me basically started out as a front crankshaft seal replacement, because I was tired of having an increasingly drippy engine for probably the five to seven years before I did the job. COVID and its forced isolation was the perfect excuse to do the job.

I have a more limited version of this project underway now. IN scope: R&R intake, power steering, tensioner, thermostat, upper timing guides, lifter oil tubes, replace lower engine oil pan gasket, new injectors, new cam seals, new caps, rotors and backing 'cups', refurbed ETA, refurb LH module, replace lower and upper engine wiring harness, R&R monowiper, replace blower motor, replace EZL & thermal paste, replace all fossilized engine rubber and vacuum lines.

 

[gerryvz]

I have a more limited version of this project underway now. IN scope: R&R intake, power steering, tensioner, thermostat, upper timing guides, lifter oil tubes, replace lower engine oil pan gasket, new injectors, new cam seals, new caps, rotors and backing 'cups', refurbed ETA, refurb LH module, replace lower and upper engine wiring harness, R&R monowiper, replace blower motor, replace EZL & thermal paste, replace all fossilized engine rubber and vacuum lines.

Very nice, and I hope that my information is of assistance to you for your project. There are a lot of resources here to help out - my thread is only one of them.

The good thing is that your car will be good for another 20+ years until the rubber parts begin degrading again, probably longer than that.

You're going to find (if you haven't already) a lot of degraded soft parts as you get into the job. I don't think most people here on the forum (or E500E owners in general) understand how these things degrade -- whether used or not used. Age just degrades soft parts, and in my opinion and experience, if a car lives in a hot climate (i.e. my 10 years in Texas) it accelerates the degradation of rubber "wear" parts (not necessarily o-rings, gaskets and such) by about 30-40%. I have seen this in serpentine belts, V-belts (M117), and things like transmission shifter bushings. They wear already, but the climate accelerates the wear.

And age (mainly ozone / air exposure) also degrades soft parts -- it just does. 25-year old sparingly used rubber is not the same as 5-year-old rubber.

 

[Ian White]

Agreed it has been helpful - thank you. Some ambiguity on manifold bolt part numbers, so I ordered 2 of each length to replace the two long 95mm front manifold bolts (one twisted off, thankfully near the head of the cap screw, the other was terrible looking). I removed the broken bolt out using a torch to create heat cycles, lots of penetrating oil and working it by threading in and out with a pair of vice grips. Oh and lots of patience's over a couple of hours. When I reinstall any steel fastener into aluminum, the bolts get a coat of anti-seize.

I tried to source locally the two long front (6,7,8mm can't remember) manifold cap bolts 95mm long. Locally I cannot find a source that carries 95mm length - it's either 90 or 100mm and haven't been able to locate bolts that are threaded the entire length of the bolt. Hence ordering from MB (supposedly they're coming from Germany)..

Agreed with the soft rubber parts. Even the soft rubber oil pick up in the pan was fossilized!

 

[gerryvz]

Yes, you have to document carefully when removing the intake manifold bolts, because there are several lengths.

You will find that your car will be running more smartly/sharply when you are done with the job. It won't be night and day, or developing noticeably more power, but everything will just feel sharper and crisper. It's a good feeling.

 

[Alphasud40]

Tech Tip: it’s always a great idea to mark how bolts were installed but sometimes we get distracted or in our ignorance we think we will remember where the bolts were removed. My tip is when you unfasten the bolt or screw take note of how far it threads into the assembly. All of the bolts you remove will have the same embedment and for a 8mm fastener it’s generally 1/2-1”. Knowing that you can loose fit all the bolts and just look at how they sit. Then just shuffle them around until they are all even. I have had to reassemble what others have disassembled over the years and knowing this makes it easy.

 

[Ian White]

Appreciate it. I make a cardboard template and stick the bolts thru to index location. When I mentioned that I ordered two of each bolts it's because I couldn't discern on EPC which part numbers were the ones I needed so ordered all three styles