Too much scoring? (cam journals)

[carwiz008]

While tearing down I noticed that a few journals and caps on my exhaust cam have some wear. A7 really caught my eye, pictures below.

I've heard mild scoring is normal... how does mine compare? Can I reuse?

If polishing is needed, how should I go about that?

[stock cam on stock springs, M50tu]
A7 journal and cap:

[flyfishvt]

How you proceed kind of depends on what your plans are. You're doing a tear down? So you're doing a rebuild? You can pick up a set of M50 cams dirt cheap. They aren't a high demand item.

[carwiz008]

Thanks for the reply, Fly. Rebuilding, yes, but I wouldn't mind swapping M3 cams later on. I am only replacing items which are in serious disrepair or are a total b!tch to change later.

I feel like the camshaft would only be the former. I'm trying to gauge if I could save this part for another year or if it looks like impending doom. Anybody have reports after reusing a cam like this?

[joey79]

From his sig, it looks like he's working on an m50b30 stroker.

That looks like pretty bad scoring. Personally, I wouldn't reuse those. m50 cams are a dime a dozen though. Have you considered upgrading to s50 cams?

[carwiz008]

Yeah I would love to have S50 or S52 cams but I'm not sure I can afford it right now. I will look around for a clean M50tu exhaust cam

[epmedia]

The aluminum looks better than the iron...
That's no the original cam for that head, is it?

[carwiz008]

I think it is. 9.0mm lift and enough oil varnish to stain a table. There was nothing during tear down to suggest the motor had been touched before.


I'm guessing that if it ran for 150k with this cam then it will run another 10-15k, or however long it takes for me to get M3 cams in the next year or so. I don't really want to drain funds on another M50 cam that I am just going to swap

[paniolo]

Those look pretty scored to me too. When you run a fingernail across it can you feel the ridges?

[carwiz008]

little bit, yup

I'll have my machinist look at it tomorrow

[sjpgoalie]

Either someone didn't change the oil for a WHILE or that thing was getting starvation. Those are some deep ridges and something definitely got in there between the bearing and journals.

[paniolo]

Whats the worst that could happen??

[carwiz008]

Is that from a failure all at once or a worn-out cam that was reused? Is there a decent chance of that happening within a year of rebuilding with this cam?

Also, anyone have a good M50tu exhaust cam/tray laying around?

[pussiwillow]

It was from a member on here who drove car with no oil pump. Just replace the cam and get matching tray with caps. You'll be looking at a hundred bucks maybe less..

[mulholland]

get m3 cams and be done with it... why waste money on the overlap of repairs and mods? The cam swap is worth it, trust me.

[sjpgoalie]

Whichever route you choose, just don't run that cam, those caps, or tray. You've already got trace amounts of metal in the motor that got chewed off of the bearing and journals.