I think I stuck a valve

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06-25-2014, 11:01 PM

#21

MILD THUNDER

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Quote:

Originally Posted by Rookie

Just got off the phone with Jim. He said the valve didn't stick. He believes the pushrod guide broke first, rocker walked over the retainer, released the keepers and spring, valve dropped and then the piston made sweet love to the valve. The stem shows no signs of heat, metal transfer and the guide looks relatively good.

Mild, AFR's are ~12.8 WFO!

Makes sense on what Jim is saying. Now to find out why it happened. I have those guide plates and haven't had any issues with them so far. Keep us posted on what u find

06-26-2014, 05:33 AM

#22

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Guide plates just guide. Should be no stress unless something else happened.

06-26-2014, 02:22 PM

#23

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Quote:

Originally Posted by SB

Guide plates just guide. Should be no stress unless something else happened.

I think my pushrod might just be touching the guide at full open. The pocket might need to be elongated considering the failure.

06-26-2014, 10:07 PM

#24

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So this is what I think is the culprit. On the exhaust side the pushrod was barely touches the the guide. Rolling over by hand there might be a few thousands clearance, but no contact. I'm sure at speed there is a little more deflation and contact is made.

[ATTACH=CONFIG]525261[/ATTACH]

Remedy, grind out the back of the pocket.

[ATTACH=CONFIG]525262[/ATTACH]

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