"Burnt" spark plugs
#1
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Joined: Apr 2010
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From: Panama city, Panama
Went out for a small run yesterday and once i got back i noticed that 2 plugs were burnt. pics below of one burnt and one not burnt. Also, one of the cylinders has no compression now. I think im taking the head of that side to check if the valves are closing correctly.
Any suggestions as to what may have caused this?
Any suggestions as to what may have caused this?
#4
Looks like detonation damage, if you really have 0 compression you likely holed a piston.
#7
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Joined: Jun 2004
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From: Omaha, Nebraska. Boat on the Mighty Mo! Longest river in the USA!
What cylinders? What year?
Whey you burn a hole in piston you will see metal all over the plug and the plug will look worse than that.
I would also go with blown head gasket.
I had a problem last year with zero compression in one cylinder, it was an exhaust seat. Valve was not closing all the way.
Whey you burn a hole in piston you will see metal all over the plug and the plug will look worse than that.
I would also go with blown head gasket.
I had a problem last year with zero compression in one cylinder, it was an exhaust seat. Valve was not closing all the way.
#10
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Joined: Apr 2010
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From: Panama city, Panama
no water in the hole. the pistons are new 4.530, block is a 502 bored to .06
i think that i have a combination of problems, thin head gasket (.03) hot spark plugs and low octane gas.
the oil was clean as well
i think that i have a combination of problems, thin head gasket (.03) hot spark plugs and low octane gas.
the oil was clean as well



