Crankshaft Sprocket, should I replace the timing chain W210, E230

[wynanddb]

This is a pic of my crankshaft sprocket. It looks like the chain wore through the plastic/rubber type stuff between the sprockets. Actually found parts of it in the sump. Engine (W210 E230) has 288 000km on the clock. Will prob need to replace the sprocket, or what do you think?, if anyone had any pointers I would appreciate it. A dead certain is that I will be replacing the chain tensioner, which was probably the cause in the first place. Had a pinking sound under load. Maybe I should replace the chain as well? Any advice will be apreciated

Thanks :grin:

 

[meanie]

At that mileage,all the sprockets,particularly should the bottom one,should be replaced if you are replacing the chain.
The bottom sprocket has an especially hard time of it as it trying to drag all of the valvetrain around with it.
Failure to relace the drive gears can result in the chain riding up the worn face of the sprocket & stretching the chain in double quick time.
This was a common mistake made on the M102 engine back in the olden days!

 

[Xtractorfan]

It is always wise to replace anything that can cause problems when you have stripped the engine down that far.. a new chain and tensioner would be my first thot.

 

[television]

I have never seen a bottom sprocket of an MB, but there is no wear on the teeth at all, a sprocket when worn has sharp teeth, the teeth look good in the picture for the valve teeth, the oil pump section has more but but nothing to worry about. It would have been better to have measured the chain wear before you took it off.


As of 01-95 the bottom sprocket has rubber impregnated off set teeth, if the chain was worn a touch then it could have sat to far on the sprocket. Looks fine to me

 

[meanie]

A profile picture of the timing chain gears would be better here.
However,you've got it stripped down this far,so I personally would bite the bullet now & be done with it.
The car has done a lot of miles.
Just my opinion,which to be fair,errs on the side of caution.

 

[television]

A profile picture of the timing chain gears would be better here.
However,you've got it stripped down this far,so I personally would bite the bullet now & be done with it.
The car has done a lot of miles.
Just my opinion,which to be fair,errs on the side of caution.

I agree, my only thoughts are that if the chain was stretched, that could have just rubbed off some of the surplus rubber, but there is nothing wrong with the teeth

The only way is to wash it down and dry it off, if there is no cracking of the rubber, the rubber that has come of could be just spare moulding rubber. There is Nothing in WIS about checking this part, and nothing on forums about it failing.

 

[wynanddb]

found cam adjuster to be broken

Thanks fot the advise so far. Decided to bite the bullet. Block at an engineering shop at the moment, cylinders was honed, crank and pistons measured. I will be replacing the main, big end and small end bearings once I receive the parts from the MB dealer. The head has also been reconditioned (valves reseated etc) by the engineering shop. I am also replacing the rings, chain tensioner, Idle valve (oil byspass during idle), clutch pressure plate, release bearing and release bearing. All seals, gaskets, etc and will be using Loctite 518 as the flange sealant (cant get omnifit FD 10 here.) Anycase, I found a very expensive part to be severly damaged, camshaft adjuster on the inlet camshaft. Look closely where the three circles is, the middle part broke loose from the outside part.

I recon what happened is that the chain tensioner failed at a low oil pressure moment (the engine had a oil leak, front crankshaft oil seal) allowing the chain to whiplash, and what went was one of the most expensive parts (R8000, roughly 600 pounds converted). Will hear later today if the guys at the wreckers could source a second hand one for me (about 150 pounds).

 

[Phoenix]

Same Problem

I have the same problem I think. Started getting a constant "knock" from the motor (After having the Head Recon'ed from an overheat), to which Merc said that the Camshaft Adjuster was faulty. Before I have to pay for such an expensive repair , My question is ... Can a Camshaft Adjuster make an Engine "knock" sound if faulty

 

[wynanddb]

My camshaft adjuster was broken, it made a knocking noise especially under acceleration. You can always ask the dealer to show you the broken part after they replaced it.

 

[Phoenix]

Hmmm Suppose ill let them Change it , Expensive Though.... Although from inside the car it sounds like the sound is coming from somewhere else, When I listen from the Tappet Cover I cant hear it....,, Just nervous I replace something this is not broken (Although I have a knock on acceleration).... Ill keep my fingers crossed , Thx for the help

 

[wynanddb]

I could here the sound clearly from the tappet cover. Inside it sounded like when an engine's timing is too far advanced, like you get preignition. I wouldn't just let them replace it, let them inspect it first. Secondly there is a easy test, in front of the engine, on the upper tappet cover housing you will see a round brass thing, that is the advance gear's magnet which activates the timing advance gear. You will see a wire on it, unplug the wire, run/drive the engine and see if it makes a difference, or if the sound changes somewhat. If it makes no change, the magnet could opbviously be faulty, but if it isn't faulty, and there is no change to the sound, not even a little bit, then I don't think its the advance gear. But like I say, don't just let them replace, let them inspect it, show you the physical broken gear - I can point you to some pictures of mine that was broken, and then you tell them to go ahead and replaced.

 

[Phoenix]

, Thats concerning , cause i alreadly tried that yesterday with not change in the sound ... , Back to Merc I suppose.....

 

[wynanddb]

where would you say the sound originates from, do you hear it when its idling, or when you rev it a bit, or only when driving. On an earlier post on another forum one of the guys said they also had the same type of noise i was experiencing but only inside the car, for that guy the solution was to replace the intermediate bearing on the drive shaft - i might be confusing this with my BMW though as far as the intermediate bearing is concerned. You said the redid the head for you and the sound started directly after, or a while after?

 

[television]

By the way the teeth did look worn on the cam sprocket

 

[wynanddb]

Thanks for pointing that out Malcolm. I have changed the broken part on the inside of the advance timing gear, as the sprocket I recieved was from a 104 engine. The second hand part dealer agreed on replacing it for me, but that is going to take a while, in the meantime I will be using the old "worn" sproket with the "new" internal gear, brand new chain tensioner and brand new chain. Before the car would do it's first 1000km I should have the right, also second hand sprocket, but I will then make sure that the teeth looks good and that it is the 111 type sprocket. At this stage my biggest concern is, will the thing start again, well should find out on Saturday and let you guys know.

 

[television]

OK and good luck, when the teeth are worn, and the chain is as well, then there is the danger of the chain riding a tooth.
The teeth are healthy regarding the height of the teeth, its just that they looked sharp, when the tips should be blunt, as on the crankshaft sprocket

 

[Phoenix]

Well to tell you the whole story, The return pipe on the water bottle cracked and caused the motor to overheat. I had the Head redone and when I got the car back I had two additional engine noises. One was a lifter noise after the accellerator was released and the other a continous "knock". So I had the lifters replaced which did not help anything (still doing the same thing). As for the Knock,,, Merc said that the camshaft Adjuster was faulty.. (Originally thought its was the belt tensioner in the front)
Anyways, if you sit in the car with Aircon off, windows closed etc etc, you can hear the knock,, Hard to say where its coming from though. When I listen by the motor i cant hear anything (too much engine noise), When you accelerate your can hear the knock, if you leave the accelerator and it goes away , but it comes back when idling.. Already spent 26K on this. So im proceeding with caution

 

[wynanddb]

ok, there is a trick when trying to isolate where the sound is coming from, take a big screw driver or some hose pype. Put one end on your ear and the other end on different parts of the engine. The noise I had was identified by the so called experts as 1. noisy lifters (checked them all, there is a procedure for that, and they were fine), 2. the little shock absorber on the tensioner (this did make the engine quiter after I replaced it, but did not resolve the main problem), 3. Piston pin knock (now I know when somebody says that go somewhere else, its a standard answer when tehy don't know) 4. One guy said he thinks it it the camshaft adjuster, he was right, when I removed the camshaft adjuster and stripped it I could clearly see the broken part. Merc charges about R8000 for the Camshaft adjuster, you can get a second hand one from Ivan's Auto in Cape Town 021 911 0761, they charged me R2000, speak to Andre. You can tell him Wynand refered you. You will need to remove the tappet cover and take a picture of the camshaft adjuster you have and mail it to them, that helps. To replace it you need to be a keen diyer otherwise get a reputable shop to do it for you, there should be guys specialising in Merc in Jhb. Maybe the best is to get the shop to remove your one, inspect it to see if it is broken, if it is, post it off to Andre, he will then find you a similar one, theyve got loads of 111 and 104 engines, post it back to you Counter to Counter - request a tracking number. The post without a tracking number takes almost 2 weeks, Counter to Counter with tracking number at the post office is 24hours during the week. Hope you get it resolved

 

[wynanddb]

oh i forgot to mention that when listening for the sound, I had the sound coming from the front of the tappet cover.

 

[Phoenix]

Thanks for the Advice ,, Lifter sound seems to be coming from Number 4 Cylinder (although i just had them replaced), and a light knock coming from the front of the tappet cover (right above the Camshaft adjuster)..I Would like to know if the camshaft adjuster get break from an overheat (Sounds Strange to me, But I only know Audi and Veedubs so...) Had a chat to andre, Will get back to me..,, So hoping this sorts out my issue with the knock, Then all i have left is the Lifter Noise...,, Thanks Again Wynandb