timing chain life
 

I have a 1985 190 2.3 8v. what is the suggested timing chain replacement interval. mine has 185000 miles on it and i do not have maintance records. the reason I ask is I am getting some rattle at rpm just before the shift. do I need to replace the chain or just the tensioner? thanks for any imput.
joe

Your engine has a single row timing chain which would normally be changed around 100-120k miles , if you don't know whether yours has been changed I think now might be a good time.
The chain ,tensioner and guides should be changed at the same time. If this is the original chain I would think you would need a cam sprocket and crankshaft sprocket if the chain is badly stretched, as the teeth will be badly worn and the new chain will wear rapidly if they are not changed.
You will be able to tell if the sprockets are worn as the teeth will have a hooked profile on one edge instead of being symettrical in profile.
Hope this helps , Geo.

I just replaced mine at 169,000 along with the guides. Just bought the car and had a feeling it had never been done. 1990 420 SEL.

Siduri19 > Where did you get your parts? I'm soon going to do my newly aquired '87 420SEL and I'm parts hunting :)

I had it done at my mercedes mechanic. You can order parts on line from Phil at this forum. He's very knowledgeable and you can get the parts delivered pretty quick.

380 is a screwed up engine with its weight-reduced single row chain. When I bought mine (with a broken chain) it had 100k on it. This is not something to fool with. If you are doing the work on your own, then get the dual gears (5 of them) and a dual chain, and new guides (they are cheap). For the gears check out your junkyard for any SL,SE,SEC or SEL engine (420,500,560). If you need "verbal" help send an email...

Sorry, I just noticed it is not a 380, so please disregard..

Had to take my '99 C230K in today. Heard an underhood noise that was identified as a tensioner problem. Car has 65,000 miles on it. I asked the tech when I should replace the timing chain and he said 100K. So about $1000 dollars later it's getting replaced along with the fan clutch and all the gaskets that go with it. I'm happy that was all it was, but unhappy that stupid things like this continue to break. Never had these issues with any other car. My last Mercedes.

Mott: Your timing chain was replaced at 65k? And for a cost of $1000? Those are both absurd and you got ripped off :eek:

joseph c: It's 21 years old with 185k and has a single-row timing chain. On an engine with overhead cams and a single-row timing chain, 100k is typically the accepted interval. If you know how to measure the stretch itself (Probably similar to the procedure listed here), do so. If you hear slap, usually a new tensioner isn't enough - even with a weak tensioner a new, tight chain won't slap. Measure the stretch, then you can tell.

Tomguy - sorry, only the tensioner and fan clutch are getting replaced. By the time this car hits 100K, someone else will be driving it!:)

$1k for a tensioner and a fan clutch?

Unless there's something I am COMPLETELY missing about new MBs you are getting ripped off by whomever you are going to, and it doesn't sound like a reputable dealer.

Phil has a fan clutch listed at $108.47 and a tensioner at $83.30

Dual timing chain?
 

Is the benefit of a dual timing chain just redundancy? Is that why it's better than the single chain?

Not exactly, but yes. It's stronger to begin with, and is less prone to both wear AND failure.

Keep in mind that the chain's life depends on the model (dual, single, etc.) and the length and path of the chain, as well as the maintenance that the engine had. The chain is oil bathed and frequent oil/filter service greatly increase the life of the chain. On the inline engines, the chain is short and has no direction changes. These tend to last longer than the chains on the V-8 cars that are very long and change direction.

M111 and M104 engines have very long loved chains thanks to the inline design and big dual-chain designs. M102/M103 engines last quite a while, but being single row, require more frequent changes. M116 engines have troublesome chain guides and should be inspected often. M117 engines are less troublesome than their M116 cousins, but being a V-8, owners should check for wear on a regular basis.

On my M102 engines, I replaced the timing chain at about 200,000km and found reasonable wear, but went ahead anyway for peace-of-mind. My current M111 engine is at 199,900kms and I doubt I'll replace the chain before 250K.