PeachParts Mercedes-Benz Forum - View Single Post - 1986 190E 2.3-16 Chain Guide Rail Replacement

JimSmith · #71 06-16-2007, 07:23 PM

Racing,

The bearings turned out to fit fine, and they are all closed up now. We did the plastigage routine to verify we had a good replacement bearing set on the least worn connecting rod bearing, at cylinder number 4, and the worst worn one, at cylinder number 2. Both turned out to be slightly larger clearances than 0.04mm (slightly greater than 0.0015 in.). Which is about nominal or a bit tight.

The odd thing we found, which may explain the appetite the chain developed for guides, is the bearing on the distributor drive gear was completely shot. I will photograph it and post some photos. But that item had been ejected into the pocket behind the bore that supports it, normally, and was quite chewed up. So is the little shaft journal for the sprocket and drive gear. The front cover side is fine, for some reason. No scoring there, or other signs of distress. So it would seem the chain was allowed to go nuts as it rolled over the distributor drive sprocket, which may have led to the lunching of the two "Kunststoff" guides - one in the head below the camshaft sprockets and above the distributor drive sprocket, and the one below the distributor drive sprocket that was mounted on those pins the chain also ate.

Anyway, anything tricky about pushing a bearing back into the bore of the block casting where the old one came out? The bore looks fine, but the bearing sure doesn't.

We will be replacing the sprocket drive assembly, and the bearing in the block. Any reason to remove and replace the bearing in the front cover if it looks fine?

Thanks,
Jim