230SL camshaft problem

[Ron]

I've taken (with the help of a great mechanic) my engine down to the bare block.  We've fixed the leaking rear main seal, found an improperly installed valve seal, which should fix the two problems it had: oil leak and oil burning.  (When purchased, the car's engine was out of the car, and been "rebuilt".  I installed it, and it had the above problems.  It's been over 3 years, and I've only put 1,000 miles on the car.)

I knew the cam had problems, about 3 of the lobes have rust pits.  Cam bearings are ok.  About 3 years ago I found a used cam with good lobes on eBay, and purchased it.  Yesterday, we're ready to apply the cam, took off the gear, and saw that the cam bearing next to the gear has grooves in it. 

Does anyone know where I can get yet another cam?  Or should I have this one welded and polished down?  Or should I have the cam bearing turned down and an insert made for the tower?  And where to go for such work?

Pretty frustrating sometimes!  The engine looks good otherwise.  I'd love to get this car on the road for summer.  Ron

[ja17]

Hello Ron,

A small groove in the  cam journal may not be a problem. Larger wear areas in the cam journal could be a problem.  If the front cam support/ bearing is bad it can be replaced by itself.  A good used cam support/bearing can even work.

A picture of the situation could help us advise.

[Ron]

Thanks Joe.  The support bearing looks good.  The grooves, and there are many across the whole width of the bearing, are on the camshaft itself.  They are deep enough to hang up your finger nail in them.  The mechanic here says it could go for a few thousand miles, but when if fails, it could shatter the support bearing and I'd have Al parts all over in the engine.  So he advises not putting this camshaft in.  (he's not trying to sell me another one, so I'm trusting his judgement. He doesn't like repairs on these, he's hoping I can find another one.)

I'll go down the to shop tomorrow and take a few pictures and pass them on tomorrow evening.

And thanks for all you folks helping over the years.  I feel like this engine will run great, and be a solid performer until I can't drive the car anymore.  (I'm 65 now.)  And it was because of the help from this site that I was able to get this far with it all.  Ron

[Benz Dr.]

I get cams welded and reground once in a while and they all seem to be working OK. It's rare to find a cam journal that's scored but I'm sure it happens.

[Ron]

Maybe this problem is solved.  I took the cam to a machinist this afternoon and he polished the bearing.  It looks and feels good enough to install in the judgements of the machinist and the mechanic helping me.  Attached is a shot of the bearing before its trip to the machinist.

As to the cam with the pitted lobes, the machinist said it could be reground for about $200.  So I guess that'll be my backup.

Lesson learned: these camshafts are not easy to find.