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.
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.
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