Clank Clank when cold....new engine time?? - PeachParts Mercedes-Benz Forum

cooljjay · #1 10-28-2014, 03:58 PM

Well it appears, that soon I will need an engine replacement but I was curious what others may think? I have been bringing my 78 back from the dead many many times...

So now, I am getting a horrible clank clank from the lower part of the engine, but it is only when the car is cold, once it is warmed up no more clank...

The car is having a horrible rough idle at the moment but I think that is due to me switching over my "rebuilt" monark injectors from my euro...I was told by a mechanic a long time ago that one wasn't firing correctly...but I don't think it would cause a clank lower in the engine..

I did an oil change a few days ago, as I thought it could be due to thick oil(former greasecar)and I cleaned out the tube that runs through the oil filter and replaced the orings..I also took a gal of diesel and poured through the oil filter housing and valve cover..removed a lot of stuff!....clank was still there...

I then checked the valves and adjusted them all including the ones I felt were too lose....clank still there

Ran some sea foam through, still there...

loosened the hard lines while running, effected the idle...and clank still there..

So I have came to the conclusion that I will just need to swap the engine out, though that will be sometime from now as I don't have the funds, tools or space to do it...

I am just going to continue to drive it, as once warmed...it runs perfect and the noise isn't there..

Though I was wondering if anyone here might have had a similar issue, and maybe it was an easy external fix per say....I will try to get a video up..

dkr · #2 10-28-2014, 04:18 PM

Have you done a compression check?

Dkr.

ah-kay · #3 10-28-2014, 04:54 PM

The problem is internal. I suspect it is broken ring or rings. I had the same problem on an OM603 engine. It also damaged the cylinder wall when I took it apart.

cooljjay · #4 10-28-2014, 05:55 PM

Nope, I attempted to check the compression awhile ago but the gauge I borrowed had to small of threads...

hmmm I didn't think about a ring, but that would make since with the rough idle, burning oil etc I have been having....when I got the car, the valves were so tight, I couldn't get the thing to start and it took a lot of muscle to break the adjustment nuts lose...

JB3 · #5 10-28-2014, 06:42 PM

post a video

leathermang · #6 10-28-2014, 07:44 PM

Check .... or better yet replace.... your ratchet , spring, oil pressure chain tensioner on the passenger side of the block...

cooljjay · #7 10-29-2014, 02:20 AM

Quote:

Originally Posted by leathermang

Check .... or better yet replace.... your ratchet , spring, oil pressure chain tensioner on the passenger side of the block...

I net that is what it is, as I noticed my pressure gauge is idling a bit lower then normal. It sounds as though it is coming from the passenger side. Whats all involved in replacing all this?

Here's a video, I started it about 6/7 hours prior so the sound is not as pronounced, if you listen deep you will hear it.

View My Video

ah-kay · #8 10-29-2014, 02:22 AM

Quote:

Originally Posted by cooljjay

I net that is what it is, as I noticed my pressure gauge is idling a bit lower then normal. It sounds as though it is coming from the passenger side. Whats all involved in replacing all this?

Here's a video, I started it about 6/7 hours prior so the sound is not as pronounced, if you listen deep you will hear it.

I would not even go there even if you can get all parts for free. OTOH. it is your car.

cooljjay · #9 10-29-2014, 03:26 AM

Quote:

Originally Posted by ah-kay

I would not even go there even if you can get all parts for free. OTOH. it is your car.

True, I am reading about it now....pretty much the pump needs to come off in order to change the tensioner. What I am seeing, is that this is a common wear item....personally I would think that replacing the 4$ tensioner would be easier then the whole engine...

Still I have no idea when I can drop the pan, see whats up and figure out if that is the issue and what is worn out..

This thread is helpful..granted its a turbo..

Oil pump chain tensioner replacement 1983 300SD

Stretch · #10 10-29-2014, 04:49 AM

You have a non turbo OM617 don't you?

Stretch · #11 10-29-2014, 04:50 AM

Oh and consider yourself told off for tipping diesel through your engine.

rscurtis · #12 10-29-2014, 10:39 AM

Sounds like fuel knock to me.

leathermang · #13 10-29-2014, 11:18 AM

timing chain tensioner

cooljjay · #14 10-29-2014, 01:55 PM

Quote:

Originally Posted by Stretch

Oh and consider yourself told off for tipping diesel through your engine.

shhhh don't call the engine police

I know, but hey its better then filling the engine with diesel and then running it for 5 mins then flushing it

Yes its a non turbo..

Stretch · #15 10-29-2014, 02:28 PM

Quote:

Originally Posted by cooljjay

shhhh don't call the engine police

I know, but hey its better then filling the engine with diesel and then running it for 5 mins then flushing it

Yes its a non turbo..

Then the tensioner is slightly different from the turbo spring and ratchet affair. It is "all hydraulic" and needs to be pre-filled with clean engine oil if it gets removed.

Furthermore the oil pump is not driven by a chain. It runs off helical gears that are driven from the intermediate shaft (between timing device and IP). The helical gear drive affair is a "known" weak point for the non turbo OM617 and the OM616 because when the parts wear you can get a shuttling effect within (that I assume makes a light tapping noise).

If you can not see any evidence that the chain tensioner is not doing its job - so take off the valve cover and look(!) + check the feel of the chain and the big chain guide - I'd be pulling off the vacuum pump and checking the intermediate shaft play. Then removing the timing device - then checking the condition of the helical gears that drive the oil pump.