Pushrod question

Bennyboy96

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Hi guys, I have a pushrod length question.I freshened up my 65 383 only to find I had no compression when it was time to fire it up. I dug through my parts boxes to find that they parts supplier sent me 68 and up lifters. No biggie. I did a search and found the different lengths for the years. But I decided to measure what I needed so I cobbled up a length tool with old rods and tapped for thread rod. Stock length for 68 and up is 8.575 mine measure 8.400 with no preload. The only thing I did was install a small RV cam, cleanup heads which took .007, had a valve job done. Is it possible that they are that much shorter or is something else wrong? Thanks in advance Ben
 

detmatt

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I have several sets of used oem ‘68 and later pushrods that you need. Your originals have a tapered end?
 

Bennyboy96

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I have several sets of used oem ‘68 and later pushrods that you need. Your originals have a tapered end?
Thanks, I probably should have asked on here first. I ordered some 68 8.575 cheapies to try. But I'm not sure they will work if my measurement is .175 shorter than the stock 68
 

Rustyrodknocker

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To me this seems to be the symptom of the opposite issue. If your pushrods were too long this would prevent the valve from seating resulting in an absence of compression.
If they were too short but long enough to stay in place and operate it would result in a loss of overall lift.
How cylinder pressure do you have?
 

Bennyboy96

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To me this seems to be the symptom of the opposite issue. If your pushrods were too long this would prevent the valve from seating resulting in an absence of compression.
If they were too short but long enough to stay in place and operate it would result in a loss of overall lift.
How cylinder pressure do you have?
The original push rods were to long. They were the 1965 ones that taper down. 8.635in I believe. Then I had no compression. I loosened the rocker shaft to see if that was the case. Then it had compression. I don't have any of the 1968 ones to try yet that I think are 8.575in. So I measured with a homemade pushrod tool to see what I needed and am getting a measurement of 8.400. I guess my question was if the 1968 ones were going to be to long also.
 

detmatt

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The sets I have are stock length, 8.57”.
 
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