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5.7 litre GM intake manifold leak

The wonderful plastic intake manifold...

My 2000 chev van with the 5.7 litre is using about 2 quarts of antifreeze every three months or so. I can smell antifreeze every once in while but can't find a leak. Lately I have thought that I could smell antifreeze in the exhaust. In the past few months I have a lifter tick on cold starts that goes away after five minutes. 50,000 miles.

What test can be done to diagnose this, what are the odds that I do or don't have the infamous intake manfold gasket leak? I suspect that it's going to cost major bucks to change this in a van...

Brian

Reply to
Brian
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Not plastic... The upper plenum is plastic, the lower (where they leak) is aluminum.

Pressurize the cooling system, look for where the leak is. Front of the passenger side cylinder head is the frequent bet.

Odds are good. have 'em do the water pump right away since they usually leak within a month of repairing the intake leak.

The labor isn't a whole lot worse than a pick-up truck.

Reply to
aarcuda69062

I added coolant for a couple of years to my 96 chevy pickup with the 5.7 and did exactly as aarcuda69062 suggests. "Rented" a pressure tester from Autozone. After a couple of pumps on the pressure tester the coolant was obviously running out of the gap between head and intake on the passengerside near the front of motor.

Reply to
bob

Thanks, I have a pressure tester so I will try this once it's warm out. I thought for some reason that the leaks were normally internal to the engine, so you wouldn't see anything external.

Brian

Reply to
Brian

Brian, mine was external but I believe some was internal also as there was lots of goo in the intake on that side to the front. Based on the looks of the failed gasket, I'd also say it could leak either direction. May be I was lucky but my cousin's failed to the outside also so maybe this is common. That is about the extent of my experience on this subject.

Reply to
bob

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