m111 startup rattle

[Arzaam]

Hi guys I have a 2002 c180 m111 NA engine done 80k miles and running on Mobil 1 0W-40 oil with oil changed every 2k miles as I dont drive it often. since I have owned it 3 years + it has always made a rattling sound on cold startup that lasts 2-3seconds when not started for more than 3 days. I have read extensively about this issue on this forum and had asked previously before also, many said it was the lifters and common on m111 to make noises like that, dealer said the same though they said might be chain tensioner but they said they cant order any parts for m111 any more in South Asia so I did nothing about it. Recently reading some threads on this issue I thought illl ask once again if its safe for the car and what are my options considering it wont be worth opening the head to see if its a chain or lifters issue especially when I cant find any parts, the best I can do is swap it to a M111 Kompressor engine as I cant find parts for a NA one. any had this issue before, to me the rattle sounds rattlier than the tick tick of dry lifters but at the same time the rattle is not a quick high rpm rattle like I have heard chains on m271 sounding when bad, its almost like a misfire rattle. there never been any codes or other issues while driving, pulls strong on the rev range, should I loose my sleep or not? Should I consider starting it and idling for a few min every 3 days just for this reason?

 

[Uncle Benz]

It sounds to me like the oil filter housing is draining down over the few days of standing, and has to refill before the engine receives full oil pressure. Perhaps the valve in the oil filter housing makes a poor seal?

 

[Arzaam]

It sounds to me like the oil filter housing is draining down over the few days of standing, and has to refill before the engine receives full oil pressure. Perhaps the valve in the oil filter housing makes a poor seal?

thats a good point never thought of that, does the whole oil filter housing needs to be changed or can the check valve be bought and changed separately? as long as no oil pressure warning comes out can it do much harm?

 

[Arudge]

Along the same line of Uncle Benz it could be a tappet draining down as well. Noisy until the pressure comes back.

When my M111 had a bad cam chain it would rattle on rising revs, and also rattle on falling revs, it was quite when the rpm was constant.

Any chance of a short video of a cold start?

 

[LostKiwi]

My old m111 had a broken spring in the variator. As it passed through 2000 rpm it would make a short rattle. Easily checked by disconnecting the cam actuator wire on the side of the magnet.

 

[Arzaam]

Along the same line of Uncle Benz it could be a tappet draining down as well. Noisy until the pressure comes back.

When my M111 had a bad cam chain it would rattle on rising revs, and also rattle on falling revs, it was quite when the rpm was constant.

Any chance of a short video of a cold start?

at what milage did your chain went and was yours the kompressor one ad was the noise that you described of your chain easily heard from the cabin? ill try to get a video tomorrow, its smooth while revving or slowing down other than the quite rattle of the cam advance magnet, which I did check just as Lost kiwi said

 

[Arudge]

at what milage did your chain went and was yours the kompressor one ad was the noise that you described of your chain easily heard from the cabin? ill try to get a video tomorrow, its smooth while revving or slowing down other than the quite rattle of the cam advance magnet, which I did check just as Lost kiwi said

105,000 miles, kompressor, yes. I don't recall hearing the rattle from the cabin, is was messing in the engine bay revving the engine when i noticed.

Sounds like a broken spring and possible tappet rattle.

 

[Arzaam]

105,000 miles, kompressor, yes. I don't recall hearing the rattle from the cabin, is was messing in the engine bay revving the engine when i noticed.

Sounds like a broken spring and possible tappet rattle.

Here’s the vid I took it today

It’s a cold startup after sitting for 25 days not started, the noise seems more pronounced with the hood open and in meeting a metal roof garage normally it’s not heard much in the cabin during startup

Today I was at the dealer for a different purpose and while there had them listen to the chain and other components using a stethoscope, while idling or revving up and down they couldn’t hear anything odd about the chain, I showed them this vid and they said it could be lifters or talked about some springs in meeting oil drain back valves in the bottom end, they said a chain wouldn’t stop rattling after oil pressure got up and if so would be heard on the stethoscope, they also said even if I asked them to put a new chain and tensioner etc they wouldn’t be able to as they have never done it on this engine and wouldn’t know how to set timing correctly nor do I know any Indy that does. What’s your view?

 

[Arudge]

That noise is classic lifter rattle, sounds terrible but it sounds a lot worse than it is. Some lifters can be rebuilt but i'm not sure these can or if you can get these parts.

they said a chain wouldn’t stop rattling after oil pressure got up and if so would be heard on the stethoscope

I agree, and if it's not rattling that's good news. The tensioner on the M111 does use oil pressure but also uses a spring and a ratchet. As the chain stretches, the tensioner moves forward to keep it tight, once it has moved forward it can not go back because of the ratchet. When the tensioner comes to the end of it's travel it will stop moving forward, as the chain continues to stretch it will start to rattle and you will hear it, although it is not load and you won't hear it in the cabin.

I'll explain how to check to cam timing later, it's quite straight forward and you will know how much life is left in the chain.

 

[Arzaam]

Thank you so so much this makes everything much clearer
Would really appreciate guidance on how to check timing, thanks again this forum is a life line.

 

[LostKiwi]

As Andy - lifter rattle and it goes away pretty quickly so I wouldn't be overly concerned.

 

[Arzaam]

thanks again yep normally if started in a week within 2-3 seconds or a little longer as above, btw just for knowledge purposes generally what causes timing chain stretch especially, is it harsh acceleration up and down the rev range or cold starts till oil pressure gets up or neither just age.

 

[LostKiwi]

what causes timing chain stretch

Age, poor maintenance, incorrect oils.

 

[Arzaam]

what do you think of mobil 1 0W-40, its the one I have always used, some people recommended to me to use 5W-50 or thicker oils on this motor but it never leaks or consumes oil I assumed 0W-40 would have best lubrication and properties and would last me a year being fully synthetic as miles done is very little.

 

[LostKiwi]

what do you think of mobil 1 0W-40, its the one I have always used, some people recommended to me to use 5W-50 or thicker oils on this motor but it never leaks or consumes oil I assumed 0W-40 would have best lubrication and properties and would last me a year being fully synthetic as miles done is very little.

Anything that conforms to MB229.5 for petrol engines of MB229.51 for petrols or diesels.

229.51 is a diesel low ash oil but it works well with petrol engines due to having an enhanced detergent package.

 

[Arudge]

Chains stretch as part of normal wear and tear. The link pins wear and the chain becomes sloppy, there's a lot of link pins and they don't have to wear much before the chain stretches. I think the chain is about 1.2M long and mine stretched about 7 or 8mm, which is a lot for a tensioner to take up.

As LK has pointed out, poor maintenance because the oil hasn't been changed will wear the chain, so will poor quality oil.

Fast driving or aggressive acceleration will not make any difference, poor quality oil will. Stay with the spec and change it on time.

Watch the video below. This is NOT THE CORRECT WAY to check the cam timing but it does show you were to put the pegs. Please ignore the counting and the paint marks, just see were the pegs go. You do not have to strip the engine down to do this, just take the cam cover off.

This is what you do. Set the crankshaft at 20 degrees ATDC (After Top Dead Centre) and put a 5mm peg into the INLET cam, make sure the peg goes through both holes in the cam cap AND into the cam wheel. If the peg does not go into the cam wheel, rotate the crank clockwise very, very slowly until the peg goes in, check the reading on the crankshaft pulley, it should be between 20 degrees and 30 degrees. If it's 20 degrees the chain is new, if it's 30 degrees the chain is worm out and should be replaced. Remove the peg from the inlet cam and place it into the EXHAUST cam. Again, if it doesn't go all the way into the exhaust cam pulley, rotate the crank very slowly until it does, check the reading on the crank, it should be no more than 35 degrees. Again, if the the crank pulley shows 35 degrees the chain should be replaced. But it would probably start rattling by then anyway.

When i changed my cam chain the peg went in the inlet cam wheel at 23 degrees and the exhaust was also 23 degrees. The engine ran very smooth.

 

[Arzaam]

thank you so much again, and just to be sure after you changed the chain your readings for both cams was 23degrees which was acceptable as it was near to 20 correct? when checking this method the valve cover gasket should also be replaced right? and the cam magnet and coolant pipe on the front needed to come off to get the valve cover off right?

 

[Arudge]

just to be sure after you changed the chain your readings for both cams was 23degrees which was acceptable as it was near to 20 correct? Correct. I used a Fiebi chain, if i used a genuine MB chain i MAY have got a better result, but i was very happy with the result i got.


when checking this method the valve cover gasket should also be replaced right? I didn't and i didn't have any leaks. My cam cover has been off a few times and it's always sealed.


and the cam magnet and coolant pipe on the front needed to come off to get the valve cover off right? No. There is no need to remove the cam magnet or the coolant pipe.

You remove the red cover, remove the coils, the spark plugs (this will the engine easier to turn) move the wiring for the spark plugs to the side, unplug the cam position sensor and any vent pipes. Remove the screws and the valve cover will lift straight off. A light tap with a mallet may be needed if it's been on a long time.

In the video, he had removed the front cover to fit the cam chain. If all you want to do is check the cam chain then you only need to remove the cam cover.

 

[Arudge]

I checked my old chain before i removed it, it measured 30 degrees for the inlet and 35 degrees for the exhaust. Completely worn out.

 

[Arzaam]

got it thanks again for the detailed and comprehensive reply!