Question about 1999 Mercury Grand Marquis

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Water on top of the pistons...

My friend's Grand Marquis 1999 got overheat because the water was leaking from the intake manifold.And after we got all the parts to fix it we found out tha it has water on top of two pistons.But the strange thing for us ( we are not experts... ) is that it does not have mixed oil in the radiator, and does not have mix water on the engine. Just clean water sitting on top f two pistons... Any information will help...Thanks.!

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  • s_pra_army
    s_pra_army May 11, 2010

    did your friend maybe go through a puddle and/or make a big splash? If so, he may have sucked water through the air filter and into the intake manifold. If thats the case, he's lucky he didn't hydro lock the engine and break connecting rods or the crankshaft.

    send me some more details if you could, also, I'm not entirely sure what you are asking.


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So you took the heads off as well? If you took the heads off and let sit over night condensation built up on pistons just wipe clean and install head gaskets and tighten to specs with new bolts. But if you took heads off and antifreeze come pouring out you have a bad head gasket change both sides. The reason it has not leaked into the oil pan yet, cause it has not gotten bad enough to do so. Believe its a mess.

Posted on May 08, 2009

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