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Damaged Water Pump and Timing Cover Cause Coolant Burn?

3800 V6

As the title states, could a damaged water pump and cracked timing cover/gasket allow coolant to get into an area of combustion? Or, is this evidence of something more serious?

The timing cover has coolant channels in it and was hairline cracked during an accident; the gasket also shifted and broke. Coolant now leaks from the gasket when the system builds up pressure.

Coolant is clearly being burnt and expelled from the exhaust. It’s visible at idle only, but there have been one or two significant “puffs.”

I found a few posts on other sites about replacing timing cover gaskets to solve a burning coolant issue (on Ford engines), but this seems strange to me.

If this is the vehicle you hit the pothole with I do not understand why you just don’t replace it.

The Ford 3800 V6 is notorious for blowing head gaskets. It sounds like yours has joined thousands of others.

It’s a GM V6, I believe?

They were just mentioning Fords. They have a Buick that probably needs to be put down.

If it’s a gm v6 3800 there is not a passage that goes to the cylinders. If you have repeatedly ran it low on coolant you could have blown a head gasket or damaged a head.

Or upper/lower intake manifold gaskets?

Tester

The GM 3800 V-6 does not have a history of head gasket failure problems. I mistook the OP’s mention of “on Fords engines” to mean that was the problem engine. Please excuse me.

I’m guessing the plastic upper intake is cracked between the coolant and egr passages.

The OP already admitted a cracked intake manifold. I don’t understand where they are trying to go.

hmmm … the timing chain cover, if that’s what you mean, keeps the oil confined to the timing chain and not spraying all over the engine compartment. If that cover also is intimate with coolant passages, which could be the case, and it got a crack in it, coolant could get into the engine oil, and oil could get into the coolant. Coolant in the oil could make its way into the combustion chambers in small amounts I suppose, since oil is used to lubricate the combustion chambers.

As far as a damaged water pump, that could cause engine overheating, and engine overheating often results in a damaged cylinder head, or at least corrupts the seal of the gasket, and that would very likely indeed allow coolant into the combustion chambers.

There is no coolant in the oil and the oil is not leaking.

Engine passed test on the head gasket.

Perhaps the manifold gasket went.

At this point I’m just really curious as to how this is happening.

There’s a breach. The intake manifold seems like the No.1 suspect. Either a gasket has failed or the intake is cracked. Coolant flow into the intake can mimick BHG symptoms.

As asemaster and busted knuckles said the plastic intake gaskets and intake manifolds are known for problems. They are not that difficult to replace.