Rocker roller coversion for 502 - push rod length? - need valve train expert
04-22-2016 | 05:11 PM
#51
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From: Lake Charles, La
[ATTACH=CONFIG]554475[/ATTACH]
#1 cyl intake
Does this show the pushrod is a little too long?
what about the marks only on the forward 2/3rds of the stem. Is this ok? I ground the stems and tried to get them real flat.
#1 cyl intake
Does this show the pushrod is a little too long?
what about the marks only on the forward 2/3rds of the stem. Is this ok? I ground the stems and tried to get them real flat.
04-22-2016 | 05:17 PM
#53
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From: Lake Charles, La
[ATTACH=CONFIG]554477[/ATTACH]
cyl #3 intake
marks only on the forward half. ?????
looks like it is closer to the right pushrod but maybe still a little too long. ???????
end of pics.
cyl #3 intake
marks only on the forward half. ?????
looks like it is closer to the right pushrod but maybe still a little too long. ???????
end of pics.
04-22-2016 | 05:31 PM
#54
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From: westville, NJ
you ground the stems to get them flat? by hand with a grinder? then they are nowhere near flat. they need to be machined flat and micropolished. I think the valves need to come out and have the tips refinished.
04-22-2016 | 05:33 PM
#55
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From: chicago
Pattern look fine to me, i wouldnt be afraid to run it.
You could try a shorter pushrod on the intake, but my guess, is that the pattern is going to get wider by doing so.
That doesnt help your issue though, of the polylocks having very little thread engagement. What i have done in the past, is use a hardened washer, like an arp head bolt washer , under the stud. That was with regular 7/16 stud mount arp studs, that had a little longer bottom shanks.
You could try a shorter pushrod on the intake, but my guess, is that the pattern is going to get wider by doing so.
That doesnt help your issue though, of the polylocks having very little thread engagement. What i have done in the past, is use a hardened washer, like an arp head bolt washer , under the stud. That was with regular 7/16 stud mount arp studs, that had a little longer bottom shanks.
04-22-2016 | 05:33 PM
#56
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From: Lake Charles, La
I measured my pushrods close as i could and got
intake 7 and 21/32" that's 7.656" just dividing the fraction
exhaust 8 and 21/32" 8.656"
stock rods per Mercury marine for my particular serial number engine is
intake 7.592" so mine are 0.064" too long
exhaust 8.569" mine are 0.087 too long
from the looks of the marks a slightly shorter rods should do it. Unfortunately no store here in town stocked a push rod adjustable checker so I went ahead and in the interest of time, ordered new GM pushrods at a decent price through a chev dealer i know and will be here tomorrow.
intake 7 and 21/32" that's 7.656" just dividing the fraction
exhaust 8 and 21/32" 8.656"
stock rods per Mercury marine for my particular serial number engine is
intake 7.592" so mine are 0.064" too long
exhaust 8.569" mine are 0.087 too long
from the looks of the marks a slightly shorter rods should do it. Unfortunately no store here in town stocked a push rod adjustable checker so I went ahead and in the interest of time, ordered new GM pushrods at a decent price through a chev dealer i know and will be here tomorrow.
04-22-2016 | 05:34 PM
#57
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From: westville, NJ
04-22-2016 | 05:38 PM
#58
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From: Lake Charles, La
I used a good valve grinding machine my brother uses frequently. I'm no expert but thought at the time I did them quite flat, grinding very slow and light at the finish. Just wandering if maybe only like a fraction of a thousandth would show up like that but not really be an issue.
