zeronero thinks like a naive child!

What if the timing chain broke when he was driving in the middle of a night and on a long trip.

You may not need to care for your car, but your safety needs your attention my friend....

We have my wife's 400E in the shop right now, in what has turned into a monster job, alleviated only by my mechanic's willingness to go easy on me (they service 3 MB's and more for us)

The car is at 180K, was starting to make noise at cold startup. I had bought the chain, guides, and gaskets last spring, and just hadn't gotten around to scheduling the job. Needed to take the car on a long trip, and decided to get the chain done.

Turns out the upper rails were grenaded. My mechanics can't believe the chain didn't slip a tooth: probably my wife's driving style. They couldn't find two of the rails at all, just a bunch of pieces down in the bottom, and the pins. SO, I dodged a bullet....

...except that the lower rails were broken, as a result of the lack of any other guides to stay that slapping chain. My guys say they have never seen lower rails that needed replacement, 12 years each in the MB repair business.

Front cover comes off, which means heads come off (they share the head gaskets), water pump, the ac compressor, ps pump, alternator has to float on its harness, oil pump and chain removed, etc, etc. When you're that deep in, you do the water pump, all the cooling hoses, the high pressure ps hose, the engine mounts, valve job, etc. Add a crack in the radiator neck, a harness on its way out, and you're having a real party!

We got the car at 150K, and it ran smoothly to date. The noise at start-up wasn't much worse than noisy lifters, and never got real bad. We found lots of sludge in the heads and carbonned piston heads, which we attributed to the previous owner, as it has only seen mobil 1 and premium gas during our ownership. My guess is also that the timing can't have been perfect, given the state of affairs above.

Do your chain at 150K, noise or no noise. I agree with Nguyen: whether you can afford a complete overhaul including rods, you don't want to grenade an engine 2 hours into a six hour road trip.

It's a lot of money for a 12 year old car, but ours is in nice shape, the interior is almost mint, nice paint with only a few imperfections, great stereo, we got it for a reasonable price, and the wife loves it, esp. the V8. And I will NEVER buy another MB V8 unless it's new (haha) or the chain has been done.

Maybe we paint it a new color, something lucky!

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Peter
1985 300TD 4-speed 212K
1992 400E 343K
2001 E320 72K

Peter,

So..... lots of sludge, carbon buildup, and atypical destruction of most rails. What kind of service did this beast get before you bought it? Sounds like it was neglected a wee bit...

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Steve
'93 400E

Don't know for sure, Steve, we've had the car for a bit over a year now, synthetic all the way, so the sludge was a surprise. I would have thought the engine would have cleaned up. It seems to have been a timebomb!

We bought the car from a wholesaler who found out the car needed a blower motor and sold it to us cheap (I know, I know). The car was and is very clean, and seemed mechanically okay. My mechanic got the car for a diagnosis and called me.

I would have been totally devastated (and the recipient of some hard stares from my wife, who relies on my automotive judgment) if we had blown the chain while driving, a big sigh of relief there.

Like everyone here says, know the car you buy or don't buy. Or be prepared for lots of overdue maintenance and worse!

We wouldn't own the car if not for my mechanics. They do MB's. When they go out of business, I find another mechanic who I like, and I drive the car he/she specializes in. I love these cars, but they are out of my maintenance price range without friends in the business. MB's are not for the faint of heart! They do make the heart stir, though!

what am i saying, i might have to go back to doing the wrenching myself before I abandon the faith....

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Peter
1985 300TD 4-speed 212K
1992 400E 343K
2001 E320 72K

....my tech runs across a lot of cars that seem to result from owners who buy "the star", then gasp when some major ($$$) repair is called for, and promptly look to dump the car.

Which is why a used MB can be a good deal.

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Peter
1985 300TD 4-speed 212K
1992 400E 343K
2001 E320 72K

Valve job?!! You don't need a valve job. Period. You really don't have to remove the heads either...

Having more of the same kind of fun with my 16 valve. Started 10 days ago, and still in the proccess cleaning and preparing a parts list. This car was bought knowing it was rode hard and put away wet. Many of the known squaks are now revealing their origin.

Squak List;

Oil leaks
Timing Chain, Guides and Tensioner
A/C Clutch
Power Steering hoses
Cruise Control Actuator mounts and linkages
Starter rebuild
Heater Blower Motor
Heater core or valve leak
Climate Contol vacuum actuator rigging
Install Seater Heaters

This list keeps on growing, suspension and steering are for summer repairs. Still amazed at how many bolts have to be removed to get at any thing, of course you wouldn't if a bolt is missing either!

With all the pain involved, I still love the car! This restoration will just add to the miles of smiles that I get from driving down the road!

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'87 190E 2.3-16
Heated Seats, Graphite Dash,
Delsing shift bushings

How do you guarantee not to damage the original head gasket without at least loosening the heads? I was there when we pulled the front cover without the heads on and it required a good bit of persuading.

With the sludge buildup in the heads, would you have told me to leave them be? What better time to do a valve job on a car with no history?

If you are worried I have gotten bilked out of additional $$, I am sure I have not. My tech tries to save me $$$, and I try not to ask him to kill a lot of time taking chancy shortcuts.

Some things are penny-wise and pound foolish. Pay for the labor once.

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Peter
1985 300TD 4-speed 212K
1992 400E 343K
2001 E320 72K

Just because you had sludge in the engine doesn't mean by far your valve guides are worn or even close to it. 119 valve guides rarely wear until they have well over 300000 miles on them. 50% of your project was to recondition the valvetrain.

Not pound foolish...just wise and pennysmart. A valvejob at your mileage is just flat out foolish. I'll bet your machinest will find nothing wrong or nothing wrong enough to even mess with the valvetrain.

Satish

Satish: you still didn't say how you get the front cover off cleanly, or is that a trade secret?

My techs indicated that they didn't expect the valve guides to be a problem, but since I had the heads off, might as well boil out the passages, inspect all the valves and re-cut the seats.

You are probably a better mechanic than I, but from what I know, most of the labor is disassembly and assembly of the engine, not the heads. 1/2 hour on the exhaust manifolds and camshafts, and hour for the valves themselves, my actual time (iwith a hand or two on the valves), to break the heads down.

These engines are bullet-proof except for the chain and rails, I agree, and if I were paying an MB dealership, I might do as you recommend. But...

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Peter
1985 300TD 4-speed 212K
1992 400E 343K
2001 E320 72K

Well, perhaps you didn't read Bob Johnson's post that actually started this thread! He removed the front timing cover without pulling the heads...no problem. You simply didn't need to do it. It would save you hundreds.

Most of the labor IS in pulling the heads, machining the valve seats, resetting all 32 valves, rocker arms, cam towers, camshafts, head gaskets, etc. 1/2 hour for valvetrain and a few hours for heads? Clearly you haven't taken apart one of these motors before...

Like I said, I just did.

What I said was once the heads were OFF, taking them apart is a few hours work.

didn't encounter any rocker arms, if I recall...but, like I said you are probably a better mechanic than I...

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Peter
1985 300TD 4-speed 212K
1992 400E 343K
2001 E320 72K

I see a lot of post talking about a repair manual CD. Where do you purchase a CD,do they make one for a 1992 500SEL,what is the cost,Thanks Bill

I have done 3 119 engine timing chains and lower rails without removing the heads or the oil pan. The trick is to get a thin piece of flashing like you would use on your roof. Take the flashing and bend it at a 90 degree angle and bolt it to the front of the heads. Oh buy the way this is a two person procedure. Trust me... I ruined a head gasket trying it by myself. The next step is to line the front cover up so that you can go straight in without wasting to much time. Next have the other guy guide the oil pump chain thru the slot at the bottom of the cover. Once this step is complete, use the mercedes loctite sealant and seal both sides of the cover. At this point the cover is ready to slide in. Now the most crucial part of this job is to use aircraft sealant on the top of the cover and on the bottom of the head gasket so that it will slip in easier. Take two bolts just as reference and put them in the cover at the half way point. Now you have about 25mm of distance between the go or no go portion of this program. Take somemore of the aviation sealant and layer the bottom of the cover as well as the top of the oil pan. Lightly tap on the cover with a rubber mallet while tightning up on your two bolts by (HAND). At this point you will notice some slight binding. This is caused by the other tech getting tired of holding the oil pump drive chain. Tell him to suck it up because you are almost there. You will have to do some manuvering of the oil pump drive chain to get it past or you can replace the chain and roll it in instead of fighting with it to get the cover to go past. Now you only have 15mm left and you are locked in!!. Check your head gaskets and the metal shims to make sure they are not binding and continue to walk it in untill it is flush. I cannot take the credit for this knowledge as MB DOC was the one that led me step by step thru the whole process on my first attempt.

Nothing beats a failure but a try!!!

Oh PS

You only have 15 minutes max to get that cover locked in as the loctite will harden up on you

Got a product name and/or part number for that "aircraft sealant"? Is there any MB sealant recommended for the top & bottom gaskets (at oil pan & cylinder head) what will work, for sliding the timing cover back in with the bold pan+head gaskets?

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