1992 Mercedes 300CE M104.980 ticking noise...
 

Some of you might know that I recently got myself a new project...Already installed a new water pump, second last one available from the dealer and a job from hell. Now the car is running, but not without hiccups, it's going to be a adventure. The car idles rough and will stall after ten to 15 minutes and won't restart 'till the engine is cold again.

There is a ticking noise coming from the front of the engine and is hard to pinpoint (see the video in the link below). Any ideas?


https://www.youtube.com/shorts/nnt2ygRvafs

Is the noise from under the valve cover or out front by the accessories/belts?

M104 water pump...fun.

Wire harness looks bad in the video.

Good luck!!!

Not sure, it's coming from the front. I will take off the belt and see what happens.

Yes, wire harness is a mess, being it a '92 I don't think it's the bio-degradable yet (?).

Being it a 1992 300CE with all the rare engine parts something I definitely need.

Was the noise there before the water pump install?

Not really sure, when I got the car the belt was disconnected because of the vaulty pump. Why do you think it could be the water pump?

Don't think I would be able to mentally survive a bad new water pump...

A stethoscope with a steel rod probe is the best way to localize all kinds of noises when it comes to rotating parts. During my MB career it paid for itself a hundred times over....

Could the ticking be a collapsed hydraulic valve lifter? It happened to my erstwhile '84 190E 2.3. I know your engine is a different design, but I assume it has some kind of hydraulic clearance compensator in the DOHC valve train.

Duke

One of these?

https://www.pelicanparts.com/More_Info/PEL005965SCH01A.htm?pn=PEL-005965SCH01A

Yes. Don't let the tip hit anything rotating like the fan while using it...you won't do it twice.

Lol, I can only imagine. It's funny, yesterday I installed new eibach springs on my 300SE, I'm more sour installing those springs than I am after lifting weights and cardio for an hour in the morning...

Haven't done much work on the 300CE in the last couple of weeks, had to give my 300SE a little bit of love instead. Lowering looks good on the W126, will definitely do the same with the 300CE after I sort out all the engine issues and tackle the suspension.

Didn't realise the M104.980 was only used for three years and just in two low volume models, at least in the US (300CE and 300SL), making finding parts pretty damn hard and in some cases very expensive.