a internal coolant leak in the cylinder will steam clean the spark plug--it will look like new-
Running the engine hot with the radcap off, look for
bubbles--exhaust compression gases in the coolant.


My GMC has a bad case of ship fitters disease!
GMC: Get More Cash...
1958 GMC
1956 Chevy 1500 Hydraulic Dump Truck
1952 Chevy 1700 3-Ton Firetruck

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