GT2-3 Cam is in and....(problems)-Please help!!
03-03-2006, 10:15 AM
#31
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I had the same problem and after 4 sets of lifters and 4 different length pushrods, its finally fixed. I finally ended up with 7.300" length pushrods in mine. I was having to much preload on the lifters. Comp Cams said I needed .001"-.002" preload. Now its just right. The longer pushrods were putting to much preload on the lifters. Its holding the pluger down to far for it to fill up with oil, and it was letting it run dry and that is what the tapping noise is.
03-03-2006, 10:33 AM
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Originally Posted by 1badsilverado
I had the same problem and after 4 sets of lifters and 4 different length pushrods, its finally fixed. I finally ended up with 7.300" length pushrods in mine. I was having to much preload on the lifters. Comp Cams said I needed .001"-.002" preload. Now its just right. The longer pushrods were putting to much preload on the lifters. Its holding the pluger down to far for it to fill up with oil, and it was letting it run dry and that is what the tapping noise is.
03-03-2006, 10:40 AM
#33
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I started with 7.35" then With a new set of lifters I put 7.4". Got a little worse, so then I called Comp up and the guy told me to try 7.425", and that was really bad. So then I told myself, go the oppostie way that the guy told me and it worked, 7.300".
03-03-2006, 12:23 PM
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Originally Posted by 1badsilverado
I started with 7.35" then With a new set of lifters I put 7.4". Got a little worse, so then I called Comp up and the guy told me to try 7.425", and that was really bad. So then I told myself, go the oppostie way that the guy told me and it worked, 7.300".
03-03-2006, 01:19 PM
#35
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Its hard to say to you see how much preload you have. Just start with the stock length and go from there. See how much preload you have to figure out whether you need shorter or longer p/rods.
03-03-2006, 04:19 PM
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Base Circle
Originally Posted by j's01silverado
How do you check pre-load?
That's not perfect, but should put you close. Ideally you have to check the wear pattern on the valve tip. I usually paint mine with a sharpie, set my rocker adjustment nut, rotate the engine once or twice, then disassemble and check the pattern. it should wear evenly across the valve tip. if it's worn unevenly towards the intake then you need longer and vice versa.
Correct valvetrain geometry is critical to longevity and operation!
Everyone else is right...check the pushrods if they are open or not. Lifters might be shot.
Just some more fuel for the fire
03-05-2006, 05:52 PM
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UPDATE:
Cody and I retorqued the rockers and put some red tite or whatever its called on the bolts, turned on the truck and seems like the noise went away!!!
for now?? I'll give some feed back in the next couple of days....
Cody and I retorqued the rockers and put some red tite or whatever its called on the bolts, turned on the truck and seems like the noise went away!!!
for now?? I'll give some feed back in the next couple of days....
