White Exhaust Valves
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White Exhaust Valves I have acquired a 02 LQ4 recently, after removing the manifolds I saw that the exhaust valves have an extreme white color, almost like ash. The truck was involved in a front left quarter collision but the motor ran afterwards, for approximately 5 minutes to assure everything was fine before pulling the motor. This does not look normal and I am looking for any help or insight as to what may have caused this to happen and what to do to correct this
Looks like it was running way lean or water was being introduced to the cylinders,
I would definitely pull the heads and check the pistons if you haven't already. If it's water/antifreeze you need to look for a crack or blown head gasket.
I would definitely pull the heads and check the pistons if you haven't already. If it's water/antifreeze you need to look for a crack or blown head gasket.
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Ok, thanks. A friend has dealt with a few LS motors before and suggested it was lean from a possible vacuum leak. It ran fine before the wreck so we weren't sure if it would have happened in the estimated 5 minutes it ran after the wreck. The oil wasn't milky at all and no water loss had been noted so hopefully it isn't a crack. I'll check for cracks and the gaskets will be replaced. The heads are off now as I am doing some freshening of the motor and the pistons look fine as far as my knowledge tells me
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I had planned to replace all the valves anyway, especially after seeing them as they are, just for peace of mind. And also because they would be the only thing not replaced in the valve train with the cam swap. I'll for sure replace them now and have all the necessary procedures taken to do so. Hopefully the old white valves are fine and if everything else checks out ok then I'll hope for the best.
