M119 disaster in the works

[HarryM]

I did an oil change today and at the bottom of the drain pan there was a mound about 3 inches around and 5mm high of copper particles. Where could it have come from? The engine runs well and does not use any oil between oil changes. It has 192000 miles and in the last 74000 miles it has had oil change every 3000 miles.

Thanks

Harry
1992 400SE

[Hatterasguy]

How is your oil pressure? Any knock? What kind of oil are you using?

Nothing you can do about it, just drive it.

[HarryM]

I've been using Castrol 20w50. The oil pressure is 3 bar at starup and 1 bar at hot idle.

There is no knock or anything, but on startup the timing chain rattles for a few seconds. Could it be grinding on something? I can't think of a part made of copper in the chain path.

The chain was replaced about 50,000 miles ago by a shop that didn't know what they were doing. The chain rattled right after replacement. The mechanic told me the rattle will go away after a while..ha ha. I never took it back there again.

The copper particles only showed up at this oil change.

[Jim's500E]

I also do not know what is copper inside there to get shredded off like that.

On your rattle upon start-up...there is an up-dated oil check valve for the M119 in the filter housing that may need to be put in, there also could be a few clogged oil tubes in there. I think your car has the early metal oil tubes which is good but they still can get crudded up.

As you know, the chain should never rattle in there....possibly the plastic chain rails are done and or the chain tensioner needs replacing too.

Best of luck...hope it is a simple fix for you.

[Ron in SC]

Could it be from internal engine bearings or oil cooler?

[Oracle12345]

Originally Posted by Ron in SC

Could it be from internal engine bearings or oil cooler?

thats what im thinking, main bearings or thrust bearings are wearing out. Does your motor make any noise of bad bearings? Also is 20w-50w recommend by mercedes for your motor?

[HarryM]

I didn't mention earlier that the chain replacement 50,000 miles ago was more than just a chain. It was a full valve job, chain, chain rails, tensioner, 8 valves that got bent because one of the chain rails broke, and all hydraulic valve adjusters and oil tubes.

The shop did an OK job, other than the chain still being rattly. The total was $6000. The engine runs smooth as silk and has no bearing knock at any time.

I will take it to Enrique this time for a proper chain replacement. He says there are different chain lengths for this engine and the one in there now is slightly too long. Since the pitch of the chain links is constant, the only way a chain can be shorter must be if the chain rollers are slightly fatter.

I have asked him about the check valve in the oil filter housing (as Jim mentioned) and he didn't believe it would make any difference. There may be something to it though, since sometimes after being parked for two weeks the chain won't rattle at all on startup, and at other times it will rattle when started after two hours.

Harry

[deanyel]

I've done a couple of oil check valves and not seen it make any difference. I didn't realize there were two different chain lengths but wrong chain length sounds like a more plausible explanation.

[Hatterasguy]

Well copper is bearing babbitt material, its used in very limited places in an engine. I know the main bearings have it, it might be used somewhere else in an M119 as well, I havn't yanked one of those apart.


As long as it runs well I wouldn't worry about it. Since their really isn't anything you can do about it short of a rebuild.

[jhodg5ck]

The mains in a 119 are aluminum if I'm not mistaken..

I still need to yank apart the 119 I have sitting here..but I can't off the top of my head imagine where all that metal would be coming from..

You May be better off finding another engine, going through it and then making the swap.

Jonathan

[Hatterasguy]

Aluminum, thats interesting, I stand corrected.

[CWW]

Could the excessive bearing wear be caused by the wrong oil?