Re: Discolored valves (see pic attached)

The pic didn't come through, so I'm not sure what you are looking at. It could be a blown gasket, but what other indications did you have of a blown
gasket? What led you to pull the head for a misfire?
--
Max

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Max Dodge wrote:

Pic came through here, it looked like the intake valve was burnt near plug hole likley from detenation causing errosion in valve seat from leakage caused by the vibration from repeated spark knock.
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if this truck ever knocks, It is the quietest knock in the world! Not sure why, but I run 87 and it does not ping.
I removed the two valves and de-carboned them. buffed down the seats and did a visual inspection and saw no signs of cracking. (lots of carbon on the inside of the intake valve) put it all back together and it runs like a charm. (knock on wood)
As too the question of why I did it.. I put on new intake gaskets to fix rough running about three weeks ago. plenum gasket was blown (intake was full of oil) and I figured I had it nailed. after running it, the roughness was still there so I pulled out the spark plugs (last owner had just put them in) and noticed the #8 was rusty looking. figured it was a head gasket so I pulled it off to take a look. bigger job than I thought it would be but the truck is my hobby so I didn't mind taking a day to do it(wife wasn't so pleased, let me tell you). Any way, it is all back together so we shall see how it does over the next few days.
-Jerry

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