Anyone know wha causes this ?
Thread Starter
Race Director
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Anyone know wha 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
Last edited by MotorHead; Sep 26, 2004 at 06:48 PM.
Melting Slicks
Joined: Aug 2004
Posts: 2,063
Likes: 1
From: Beverly Massachusetts
you arnt running guide plates 
not a good idea with roller rockers. you can but you take the chance of this happening. i would install guides and cromoly rods to fix that prob. well good luck and let us know if it helps. also if you add guides and chromoly rods and are gonna use the same roller rockers move them to a different cyl and put good ones on that cyl to make sure it isnt a bigger issue causing the wear. 
not a good idea with roller rockers. you can but you take the chance of this happening. i would install guides and cromoly rods to fix that prob. well good luck and let us know if it helps. also if you add guides and chromoly rods and are gonna use the same roller rockers move them to a different cyl and put good ones on that cyl to make sure it isnt a bigger issue causing the wear.
Thread Starter
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
No I am runnig guide plates, I meant that I thought they needed to be adjusted. I have a complete CC Hi Tech roller valve train with 80 wall pushrods, solid roller lifters etc.
I was thinking that because the two bad rollers are on one cylinder the only thing in common is the guide plate.
I was thinking that because the two bad rollers are on one cylinder the only thing in common is the guide plate.
Melting Slicks
Joined: Feb 2003
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St. Jude Donor '03,'11
this is confusing.
are you running guide plates or not?
The roller rockers are not the self aligning type so guide plates are required. I don't see how anyting can wear that groove pattern in the rocker.
are you running guide plates or not?
The roller rockers are not the self aligning type so guide plates are required. I don't see how anyting can wear that groove pattern in the rocker.
Le Mans Master
Joined: Apr 2000
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From: B'Ville NY
Cruise-In III Veteran
St. Jude Donor '05
From the sounds of it, I'd look closely at that guide plate too 
I'm running guide plates with my full roller setup too FWIW, I also ran the plates on my 355 w/ the Sportman II's and Crance Gold roller rockers
I'm running guide plates with my full roller setup too FWIW, I also ran the plates on my 355 w/ the Sportman II's and Crance Gold roller rockers
Drifting
Joined: Oct 2000
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From: Shawano WI
I have to agree with Fevre. Guide plate are not just a bolt on part. They have to be adjusted to align the rocker over the top of the valve. Many times they require the mounting holes to be slotted with a die grinder to get the proper alignment. Even with the shaft mounted rocker that I use, you have to shim the rockers right or left to get the proper alignment over the top of the valve.
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Melting Slicks
Joined: Feb 2003
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St. Jude Donor '03,'11
looks like a factory defect to me. are you sure they weren't like that before?
I don't see how anything can wear the top side of the rocker like that. Its a step wear so the roller tip can't be the culprit.
I don't see how anything can wear the top side of the rocker like that. Its a step wear so the roller tip can't be the culprit.
Race Director
Joined: Mar 2001
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From: Living in the Hartland
Originally Posted by turtlevette
looks like a factory defect to me. are you sure they weren't like that before?
I don't see how anything can wear the top side of the rocker like that. Its a step wear so the roller tip can't be the culprit.
I don't see how anything can wear the top side of the rocker like that. Its a step wear so the roller tip can't be the culprit.
Thread Starter
Race Director
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
No no the roller is responsible for the wear it fits right in there, the picture is throwing you off. I don't think it is a defect because there are only 2 bad ones and it is too much of a coincidence for them to be on the same cylinder.
I think I am going to adjust the guides plates, It is still kinda wierd though because there are other ones that are a little out of alighment and they are OK. It's like there is more pressure on side forcing the roller into the side of the tip.
I think I am going to adjust the guides plates, It is still kinda wierd though because there are other ones that are a little out of alighment and they are OK. It's like there is more pressure on side forcing the roller into the side of the tip.
Thread Starter
Race Director
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
With all due respect I don't think so, I'll adjust the guide plates and be fine, should I be using stamped steel with ~ 500lbs seat pressure ?
Last edited by MotorHead; Sep 26, 2004 at 10:19 PM.
Race Director
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From: Science Bitch! Mississauga, Ontario
Canadian Events Coordinator
Originally Posted by Ironcross
One good reason is the ever so present use of high mortality racing parts on a street application.
comment
Last edited by AGVI; Sep 26, 2004 at 10:31 PM.
Melting Slicks
Joined: Nov 2003
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From: San Antonio TX
I will throw a couple of pennies in the pond. Rockers will not be perfectly center to the valve they will be just a hair off usually. I would probably take the effected rockers back and get them replaced as it looks like the roller tip itself is defective as it may just be too soft or even too hard. Hard to tell by the pic. And no if I were you I would not go back to stamped steel rockers. And yes check the guide plates as well.
Race Director
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From: Science Bitch! Mississauga, Ontario
Canadian Events Coordinator
Originally Posted by David Ey
I liked your first comment better
Yeah, I felt the need to edit, but since I was caught, what I said was...
'What kind of stupid comment is that?'