Author Topic: M42 whining noise (Read 4193 times)

Greeny · « **on:** February 12, 2024, 09:44:01 AM »

Hello guys, I need your help. Do you have an idea what is making this whining noise?

https://www.youtube.com/watch?v=LIS4VQCFiv4

As you can see, I have no accesories like power steeting pump, alternator, nothing. Propably, the only thing which can make the noise is timing chain. I have replaced all the components about 60t kms ago and this noise gradually grew larger up to this level. Visually, the camshaft sprockets look perfect, just like new, same for the crankshaft sprocket and idler sprocket. Also the chain looks like new and is not stretched compared to a new one. Do you have any idea what could this noise be?

It is M42 engine with older (e30) design of the timing chain assembly - the one with the idler sprocket instead of small rail.

monty23psk · « **Reply #1 on:** February 13, 2024, 01:04:49 AM »

Can you confirm what side the noise is coming from. Have you used a stethoscope on parts of the engine?

Greeny · « **Reply #2 on:** February 13, 2024, 08:22:55 PM »

Quote from: monty23psk on February 13, 2024, 01:04:49 AM

Can you confirm what side the noise is coming from. Have you used a stethoscope on parts of the engine?

I tried to detect the noise with stethoscope and I am 99% sure it is the from the front of the engine but I was unable to detect which part of timing chain assembly..

monty23psk · « **Reply #3 on:** February 14, 2024, 02:13:06 AM »

maybe worn guides. THey are plastic so whine might be related to chain on plastic. Does it get louder when you increase engine speed?

Greeny · « **Reply #4 on:** February 14, 2024, 10:16:37 AM »

Quote from: monty23psk on February 14, 2024, 02:13:06 AM

maybe worn guides. THey are plastic so whine might be related to chain on plastic. Does it get louder when you increase engine speed?

The guides were changed back then and they are still in almost perfect condition.. Yes, it gets louder with increased engine speed. To me it also sounds like chain on plastic or some vibration of the chain itselft. But chain is not stretched compared to a new one, guides are in perfect condition.. I really don't know.

Does anyone have any experience with too much pressure on the chain?

monty23psk · « **Reply #5 on:** February 17, 2024, 01:16:04 AM »

how is chain tensioner, was that replaced? how is your oil level and what spec you using?

Greeny · « **Reply #6 on:** February 20, 2024, 06:58:48 PM »

Quote from: monty23psk on February 17, 2024, 01:16:04 AM

how is chain tensioner, was that replaced? how is your oil level and what spec you using?

Yes, tensioner was replaced several times..

Regarding oil I use Mobil1 5w50. I also used Sunoco 5w50 but than it was no longer available so I switched to Mobil1. The car has seen many trackdays and I have a really good experience with 5w50 oil grade.

monty23psk · « **Reply #7 on:** February 22, 2024, 02:41:53 AM »

not sure where you live and the climate. Normally these older cars will need something thicker on the cold side, like 10w or 15w. I dont see this being an oil starvation issue or that oil is not lubing some of the parts to cause the whine. I know the sprockets can get worn and this will cause a noise but not sure what it sounds like.

keflaman · « **Reply #8 on:** February 24, 2024, 01:38:53 PM »

I can't pick up the whining noise you're referring to. Honestly, the engine sounds pretty good to me. If the guides are good and the tensioner has been replaced, I presume you've checked the timing chain and sprockets for wear.

monty23psk · « **Reply #9 on:** February 24, 2024, 04:21:13 PM »

I agree, it sounded normally to me too.

x3me__ · « **Reply #10 on:** June 18, 2024, 05:14:53 PM »

FINALY Somene with the same problem as me!, I have that whine for about a year now, it came when i had someone change my valve lifters and crankshaft half moon pieces (cant remember the name in english), but i dont think they come from the lifters or the thingies on the crankshaft, as they messed with the chain also, so probably something was thingtned too far?, have changed oil 2 times and there where never metal sheds or anything like that.

318ise30 · « **Reply #11 on:** June 19, 2024, 03:36:34 PM »

Bonjour,
Je n'ai pas l'impression que ce moteur tourne mal, en tout cas la vid�os n'est pas assez longue pour s'en rendre compte.
C'est le claquement au d�marrage ? Cliquetis plus prononc�s au d�marrage cela est normal, le temps que tout se remplisse d'huile.
V�rifiez �galement le serrage de vos bougies et que les c�bles d'allumages soient bien clips�s.
Bon courage

Greeny · « **Reply #12 on:** July 16, 2024, 10:02:31 AM »

Quote from: x3me__ on June 18, 2024, 05:14:53 PM

FINALY Somene with the same problem as me!, I have that whine for about a year now, it came when i had someone change my valve lifters and crankshaft half moon pieces (cant remember the name in english), but i dont think they come from the lifters or the thingies on the crankshaft, as they messed with the chain also, so probably something was thingtned too far?, have changed oil 2 times and there where never metal sheds or anything like that.

You are not the only one, sadly. There are much more people with this issue, but nobody knows the exact solution. From my quite complex reasearch I think that the issue is for 100% connected with timing chain and for 95% it is timing chain tension being too high for some reason. It seems that for the early type of M42 (the one with idler sprocket instead of small guide rail) there was different tensioner rail compared to the later version of M42 and M44. But the early type M42 tensioner rail is not longer available and it is superseded by later style and this leads to the tension on the chain being too high. There is no easy way how to decrease the tension.. I dont have a solution for this yet. Let me know if you find anything what could help to solve our problem and I will let you know once I find the solution.

Author Topic: M42 whining noise (Read 4193 times)

Greeny

M42 whining noise

monty23psk

Re: M42 whining noise

Greeny

Re: M42 whining noise

monty23psk

Re: M42 whining noise

Greeny

Re: M42 whining noise

monty23psk

Re: M42 whining noise

Greeny

Re: M42 whining noise

monty23psk

Re: M42 whining noise

keflaman

Re: M42 whining noise

monty23psk

Re: M42 whining noise

x3me__

Re: M42 whining noise

318ise30

Re: M42 whining noise

Greeny

Re: M42 whining noise