engine apart agian, another cam bearing failure

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91warrior

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yep so the top end was making a slightly different noise and since this engine had to failures of the cam bearings, i took it apart to make sure everything was alright. well sure enough, the cam bearing race on the cam was chewed up. luckily it was torn apart before any other damage was done. the thing is, this is the third cam bearing that has failed. i have all three cams and the bearing all does the same, the mushroom and grooves get worn into them. also all three of these cams are from webcam. there is no way these cam bearing races are hardened metal like they should be, because if they were, the metal wouldn't wear and mushroom a groove in the bearing race like they do. anyone have much ideas?

here are all the cams i have. the far left is from my brothers build that failed from the cam bearing, the next on is from my build in 2004 that failed in 2008 due to cam bearing, the next is the cam i just pulled out today, and the one on the far right is the megacycle 252-x1 cam that i have that is brand new and not used. you can see from the 3 webcams the way the bearing race is messed up and the megecycle how its smooth like is should be.
0328001809.jpg


one on left is from brother build in 1997 with cam bearing failure, one on right is from 2004 build that last till 2008
0328001809a.jpg


one on left is the one i just pulled out today, see the grooves, compared to the new one on the right. the one on the right is megacycle is 252-x1.
0328001810.jpg


now what should i do? i have that brand new megacycle but thats not exactly the lift i want for my set-up. the only thing i need to fix this is a cam and cam needle bearing. i think im just going to replace the needle bearing and put the megacycle cam in and see if they use a hardened bearing race on the cam. if the race is hardened, it would crack, not mushroom and put a groove in the race like those webcams have been doing. does any of this make sense?
 
Humm........Get webcam on the phone and start bitching. But on a side note.....wonder why they are wearing like that on you?
 
yea i think im going to give them a call and have a talk with them. a lot of people say it could be its not getting enough oil, but when we took it apart, there was plenty of oil sitting in the head and the needle bearing was coated in it. and also, that bearing race on the cam SHOULD be harder than the needle bearing it rides in, but obviously it isnt because the needle bearing was fine.

i ordered a new needle bearing because im not going to put in a new cam with that needle bearing after it went through that. i guess im going to find out how i like the megacycle cam and if the webcams are my problem or there is something else going on. hoping to have it back together this weekend, will let you know how it goes. i guess its good i had that megacycle cam laying around, because if the webcams are my problem, it will be a quick turn around.
 
i got the megacycle cam in today and it runs good, just gotta mess with the carb now. this cam made the valvetrain super quiet at idle but once i load the engine, something doesnt sound right and i dont like it. but i started a new thread on that. once i get the carb tuned in, ill write up a report of what i think of the cam.
 
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