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Old 06-18-2014, 07:18 PM
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Default bent push rods?

I am replacing the lifters and rockers on the Bird. I tried rolling the pushrods on a piece of glass. I get some noise, and can see MAYBE 1/32 inch of difference while they are rolling. Is that acceptable?

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Old 06-19-2014, 01:36 AM
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No bend is acceptable. ANY bend is a sign of a problem.

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Old 06-19-2014, 07:24 AM
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You should post a picture of the bottom of some of the failed lifters and give some info as to how many miles are on the cam also.
If the bottom of the lifters are not warn in a offset yet round dish like pattern than the cam lobe they rode on is wiped out also! Just sayin!

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Old 06-19-2014, 10:04 AM
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The pushrods should roll very smoothly without any "bumping".

To me bent pushrods and abnormal rocker wear per earlier thread points to interference or coil bind in the valvetrain (been there done that). Suggest that you double check to make sure spring pressures, retainer clearance to guides etc are all OK.

Also carefully inspect the bottoms of all the lifters. Any abnormal wear is bad, and if any lifters are cupped then the cam is surely wiped (been there too).

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Old 06-19-2014, 10:12 AM
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If the springs are barely coil binding, that would explain a slightly bent pushrod and wiped out cam.

I have also seen stock pushrods bend just from faster modern day cam lobe profiles, and higher than stock spring pressures. The stock pushrods were very thin wall[.040" wall rings a bell] and not very strong. I never re-use stock pushrods. I use a minimum of .080" wall pushrods now. Some applications[blower engines] I have had to use as thick as .165" wall pushrods.

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Old 06-19-2014, 04:26 PM
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Default new pushrods

I purchased new pushrods. They are only .065 wall thickness, but that is all I could find locally. They are slightly smaller in diameter than my old ones. I'm not sure what my old ones were, but they seemed to fit pretty tight in the guides. Are these new ones going to be a problem?

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Old 06-19-2014, 08:23 PM
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an old drag racer (Jim West, of the Wild Wild West funny car) who mentored me many years ago said that pushrods are kind of like fuses... if they bend, you have a problem.

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Old 06-19-2014, 11:01 PM
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Does Summit sell .080" wall pushrods ?

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