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496 BBC Lifter Rotation Issues

3K views 9 replies 6 participants last post by  TommyK 
#1 ·
Hey guys I have a freshly built 496 BBC Stroker with Scat Pro Comp internals and a Comp Solid Flat Tappet TL292A-8 Cam .635/.637 262/270 @ .050 cam. Running a set of edelbrock performer rpm heads with all new springs, lifters basically everything except my lunati 1.7 rocker arms and the comp push rods that i have. This motor sits in a clean 89' Iroc-Z

Upon the first few minutes of run time I was checking for lifter rotation by examing the pushrods for rotation as well. Every one spun at a decent rate except for #2 Intake which was static. I shut the engine down and have been trying to determine why. Yesterday i checked the orientation of the snap ring on that lifter and it was in the 11 oclock position. I cleaned the rocker arm cup and put some assy lube on both ends of the push rod and fired it up. Upon the fire up the push rod was MOSTLY static but it did make a few turns over the course of ten minutes. The Rocker was being oiled at an even amount along with the other 15 rocker arms. So i ASSUMED that maybe the guide plate is rubbing the push rod under a load keeping it from turning but the lifter must be fine. Well i had to shut down after ten minutes because oil was starting to splash everywhere once it got nice and warm (i have a pair of cut valve covers). I then examined the lifter again and noticed it appeared to be extremely close or in the same exact 11 oclock position as it was before i ran it up to 1500-2500 rpms for 10 minutes. So this has me puzzled. Is the lifter stuck and not rotating but in the proper location to feed oil through the push rod or must it be spinning? The only other thing i know to do is swap push rods and maybe adjust the guide plate. I don't want to fire it up until i get my new tall valve covers in and get some insight from some experts.


Also i'm running Brad Penn break in oil and used comps assy lube on the lobes and on the lifters. The inner springs are also removed.
 

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#3 ·
I havent removed the intake manifold yet but im assuming thats what i'll have to do next. Tech at Crane Cams said lifter rotation has nothing to do with getting plenty of oil to the rocker. But if its getting plenty of oil that tells me the lifter-bore clearance must be close. So maybe its the lifter face.

So far my last options before pulling intake is..
Adjusting guide plate
Swapping two push rods/rocker
Try to turn lifter manually with some sort of magnet/tool?
 
#6 ·
Its like looking for love in all the wrong places haha. I'm starting to realize that, this project is just starting to stress me out and i was looking to see if i could come across the right person that has ran into this particular problem before.

"You mention adjusting the push rod guide plate, you can't see if it's touching or binding? If nothing else you can look for witness marks on the push rod.

Being a solid lifter setup, we assume the adjustment isn't too tight...?"

It appears that it might be touching the right side of the guide plate so under no load you can freely spin it. The lash is set at .018"
 
#9 ·
If for any reason the bottom of the lifter is the wrong degrees for the lobe of the cam,he would be able to spin it,but would result in damages.Even as short term as he has run it,they all need to be taken out and inspected.A 496 stroker is not a small investment,so his efforts even if sounds extreme to find the reason why he is having this problem must be taken now.
 
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