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Old 07-29-2010, 05:48 PM
Excaliber Excaliber is offline
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Sounds like he had about 5,000 miles on it the FIRST time when it went belly up. Actually, thats reasonable mileage for a solid roller. While my personal research shows about 8 to 10,000 miles is about MAX life you can expect from a solid roller on the street, there are a number of instances that failed well before that mark.

So I'm kind of re-thinking this scenario. He got 5,000 out of a street solid roller, OK, that could be considered a reasonable life span. Meaning, there is nothing fundamentally wrong with his setup. Valve adjustment specs could have called for to much clearance, that will beat up the rollers. The oiling may be adequate for most other cams, but in this case, just not enough for a street solid roller. I was careful to "blip the throttle", often, to keep my cam well lubricated. I never let it idle long, I never ran it at low street rpm's. That could mean the difference between 5,000 and 8,000 miles.

It seems logical to conclude the repaired cam didn't work out and that was the cause of the second failure. All though, I wouldn't write off repairing a cam as easily as many here seem to. We don't know what the cam looked like, how bad the damage was, what kind of repairs were done. I actually considered having my solid roller repaired as only one lobe was showing very little damage, because I stopped running the motor almost immediately following the roller failure.

Max suggested the hardness may be only .020 deep, if I'm not mistaken, it is likely way less than that. I'm thinking it's only .002 deep, if that, it could well be measured in microns in fact. As such, a repair followed by a Nitride treatment, could restore the hardness. I guess, I never really looked seriously into having a cam re-ground or repaired. As such, I couldn't just automatically write off such a procedure, or recommend it.

To many variables here to reach a "solid" conclusion, were just "rolling" some ideas around. Custom grind, were the valve springs correct? Were the valve clearance specs correct? Is the oiling adequate in this case? Was extended idling time involved? Was the throttle "blipped" enough to supplement oiling?

Last edited by Excaliber; 07-29-2010 at 05:53 PM..
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