A person who's journal I read blew the head gasket on her POS van and the mechanics are trying to pull one over on her. I can understand wanting to replace the block if there has been a bad water penetration but the heads?

Anyone have an opion?

TIA

Forgot that the oiling valleys go through the heads as do the coolant lines. But unless there has been something drastic like a pistion strike then there ought not be any reason to replace the heads I can think of.

I mean its a big chunk of metal that has holes drilled in it with guides in the holes and push pins, valves, rocker arms and springs right?

It depends on the type of head and how the gasket fails. If compression is escaping into another passage, it can erode a channel in the head. I've only see this on aluminum heads. If too much metal is eroded away, a machine shop can't fix it. Another possibility is, if the blown head gasket caused the car to overheat, either by loss of coolant or by compression creating bubbles in the coolant, it could warp the heads, especially if they're aluminum. That's the only scenario I can imagine in which a blown head gasket would ruin both heads(I'm assuming you're talking about an engine with two heads.) She should have the mechanic show her what's wrong with the heads.

I'm not sure what you mean by "bad water penetration". Are you talking about cavitation?

Mr. E wrote:It depends on the type of head and how the gasket fails. If compression is escaping into another passage, it can erode a channel in the head. I've only see this on aluminum heads. If too much metal is eroded away, a machine shop can't fix it. Another possibility is, if the blown head gasket caused the car to overheat, either by loss of coolant or by compression creating bubbles in the coolant, it could warp the heads, especially if they're aluminum. That's the only scenario I can imagine in which a blown head gasket would ruin both heads(I'm assuming you're talking about an engine with two heads.) She should have the mechanic show her what's wrong with the heads.

I'm not sure what you mean by "bad water penetration". Are you talking about cavitation?

What he said