Another Worn OM60X Cam Sprocket For Me - PeachParts Mercedes-Benz Forum

oilslick · #1 08-04-2016, 11:57 PM

The last time I saw this was on my '93 300D. It was missing the cam thrust washer for some reason. I took out the camshaft and removed the timing cover and replaced the cam sprocket, chain, tensioner, banana rail, guides, oil pump chain and tensioner. While everything was apart I inspected the oil pan for "chunks" of metal from the old cam sprocket because it was worn out something awful. Got it all buttoned back up and she purrs!

I bought a '93 300SD a few weeks ago. I know, it's a rod bender, but it was complete and in really good shape cosmetically so I paid the man $800 for it and trailered it home. Put in a battery and she fired up on the second revolution and ran pretty well. I bought it planning to end up putting in a 3.0 block and giving it to my dad as a tinker project and a "Sunday" car. I dealt with a compression leak around the prechamber on cylinder #6. That remedied the miss at idle and the engine went from smoking all the time to intermittent. I have driven the car a little and I've been hearing a terrible slapping sound at speed so today I decided to just tear into the engine and find out what secrets it's keeping.

I found that the cam sprocket has no teeth, only sharp points where teeth used to be. I also found out that when the crank is placed at TDC the cam sprocket is not lining up with its respective mark. In fact, someone has made some new marks on the #1 cam bearing cap to indicate TDC I'm guessing. The cam sprocket actually lines up with these new marks. The marks were made with a small chisel it appears. I found that I could pick up the chain off the sprocket and almost completely remove it from said sprocket without removing the chain tensioner. Than ain't good.

My 10 year old son and I have worked this evening to get everything disassembled so we can lift off the head and inspect further. I'm gonna check the piston protrusion and see if in fact there is a bent rod. If I don't find a bent rod then I plan to remove the timing cover as well to inspect the lower sprocket and components. Chances are pretty good, I'm sure, that I'll be getting a 3.0 block.

compu_85 · #2 08-05-2016, 10:04 AM

Yeiks! Nice you found it before the chain jumped too far.

-J

oilslick · #3 08-05-2016, 12:13 PM

The head is off and I think I know where my slapping has been coming from. Ugh! Looks like slight valve to piston contact. I don't know how to post multiple pics to one post but here comes some beautiful artwork. Geez!

oilslick · #4 08-05-2016, 12:16 PM

The exhaust valves have a nice shiny look to them.

oilslick · #5 08-05-2016, 12:17 PM

Cruddy!

oilslick · #6 08-05-2016, 12:19 PM

All the others look like this except for #6.

engatwork · #7 08-05-2016, 01:26 PM

Quote:

omeone has made some new marks on the #1 cam bearing cap to indicate TDC

LOL

oilslick · #8 08-05-2016, 01:34 PM

Quote:

Originally Posted by engatwork

LOL

I've laughed more than once since I've torn into this thing. This will be the one that doesn't have a bent rod but everything else is bent.

oilslick · #9 08-05-2016, 02:08 PM

Why replace your worn chain when you can just make your own TCD marks and ignore those pesky factory ones trying to keep your engine running right?

They walk among us folks. Smh!

jay_bob · #10 08-05-2016, 04:12 PM

A good candidate for that "there I fixed it!" site

oilslick · #11 08-05-2016, 05:32 PM

Quote:

Originally Posted by jay_bob

A good candidate for that "there I fixed it!" site

The Red Green Show. 🙄

ROLLGUY · #12 08-05-2016, 05:58 PM

Makes me want to pull the cover on my 350SDL and look at the cam gear!

engatwork · #13 08-05-2016, 07:04 PM

I would say whoever came up with making their own mark was thinking WAY outside the box. It would be interesting to hear the story behind it.

oilslick · #14 08-05-2016, 08:19 PM

Quote:

Originally Posted by engatwork

I would say whoever came up with making their own mark was thinking WAY outside the box. It would be interesting to hear the story behind it.

Maybe they could also explain why they thought cross threading the suction hose to the AC condenser was a good idea too. 😳 There was no way to remove it. Nothing worked. I'll be getting a new condenser. 😡

The head is now disassembled and I will work on checking the piston protrusion another day. I came across a deal on a completely reworked #17 head today. The man just wants it out of his shop. A customer brought it in 2 years ago and never came back for it. The shop owner has made numerous attempts to contact him but he keeps coming to a dead end. He said he'd sell me the head for $300. I have a 3.0 block waiting on me for $500. What to do, what to do?

jay_bob · #15 08-05-2016, 08:32 PM

Reminds me of a 75 Datsun B210 I had back in the day. I bought it for $500 in the 80s.. Prior owner ran it out of oil. Friend rebuilt the engine but did not understand the concept of static timing. Distributor was inserted one tooth out of time to compensate. New bolt hole drilled to secure the distributor...