Anyone know what causes this ?
Thread Starter
Race Director
Joined: Apr 2000
Posts: 17,676
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Anyone know what causes this ?
I have been keeping an eye on the roller valve train and noticed that two of my rockers are wearing the side of tips a little. It looks like the roller is wearing a groove on the insde and there is about 45 thou play as opposed to all the others at aroung 20 thous.
All of the other rockers look brand new except the two on #4 and when they are pushing the valve down it looks like they are off center of the valve stem. I did notice a couple more that were off center but there was no wear like the ones on #4.
I am thinking guide plates because both bad rollers are on the same cylinder, but thought I would throw it out there as sometimes somebody knows exactly what the problem is
BAD ONE
GOOD ONE
All of the other rockers look brand new except the two on #4 and when they are pushing the valve down it looks like they are off center of the valve stem. I did notice a couple more that were off center but there was no wear like the ones on #4.
I am thinking guide plates because both bad rollers are on the same cylinder, but thought I would throw it out there as sometimes somebody knows exactly what the problem is
BAD ONE
GOOD ONE
Le Mans Master
Joined: Oct 2002
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From: Las Vegas - Just stop perpetuating myths please.
No clue.
That wear pattern looks like it doesn't match the size of the roller tip MotorHead. 
I would send it back to the manufacturer and see what they (thier experts) say.
U should be able to reasemble and turn the engine over to observe how the roller mates to vlv tip. Could also try some blue machinists dye just on the vlv tip and see what part of roller makes contact after turning the engine over - or use dye on that side of roller tip. But again from the pix i can't see how that groove would be shorter than the roller tip if caused by the roller.
U may be just overly concerned and looking at things to closely.
Good luck. cardo0
I would send it back to the manufacturer and see what they (thier experts) say.U should be able to reasemble and turn the engine over to observe how the roller mates to vlv tip. Could also try some blue machinists dye just on the vlv tip and see what part of roller makes contact after turning the engine over - or use dye on that side of roller tip. But again from the pix i can't see how that groove would be shorter than the roller tip if caused by the roller.
U may be just overly concerned and looking at things to closely.Good luck. cardo0
Thread Starter
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Joined: Apr 2000
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
The pic throws you off, the roller fits right into the groove. I did all the geometry checks, I have adjustable pushrods and dye. I was more interested at that time in looking at the travel across the tip and where it started and ended. I obviously did not pay enough attention to the side to side play and I never adjusted any guide plates.
I am hoping that is all it is ( guide plate adjustment ) and I will get 2 new rollers ( fricken HI Tech SS expensive ) and a lesson learned
I am hoping that is all it is ( guide plate adjustment ) and I will get 2 new rollers ( fricken HI Tech SS expensive ) and a lesson learned
Melting Slicks
Joined: Dec 2001
Posts: 2,025
Likes: 1
From: Billings MT
Man, those are never fun things to find, especially when you find out its just the tip of the iceberg! (lets hope not). It looks as if there is significant side-loading on the roller tip. This could easily be a product of a mis-aligned guide-plate. I don't think it would of caused any other damage, just get it back together with new rocker arms and double check the geometry and go beat on it before winter hits! 
Thread Starter
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Joined: Apr 2000
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
I sent the pics off to Comp Cams we will see what they come up with.
The two bad rockers were a little off to the side of the valve stem but I noticed a few others were too and they are fine.
I got a PM from someonwe that said he had the same problem with the Hi Tech Stainless rollers and got a warranty replacement and switched to the Pro Magnum series and has 14k on them now. I am glad I caught it when I did though hopefully no valve guide damage and I can get this sorted out, other than this the motor has been running perfect, could not be happier with it.
The two bad rockers were a little off to the side of the valve stem but I noticed a few others were too and they are fine.
I got a PM from someonwe that said he had the same problem with the Hi Tech Stainless rollers and got a warranty replacement and switched to the Pro Magnum series and has 14k on them now. I am glad I caught it when I did though hopefully no valve guide damage and I can get this sorted out, other than this the motor has been running perfect, could not be happier with it.
Thread Starter
Race Director
Joined: Apr 2000
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Comp Cams says it can be one of two things, either the guide plates are pushing the pushrod to one side or the holes for the roller pin were not drilled straight, I am buying new ones and sending the bad ones to them to check, if they drilled the holes wrong they will refund my money, I checked the guide plates and they looked OK, at least they looked like the other 7 which don't have bad roller rockers associated with them.
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