Pressure Build Up in My '90 Acura Legend

My seat of the pants guess would be:

A head gasket is just beginning to leak, or a minor crack is just starting in a combustion chamber area.

Put a pressure tester on the car, and drive. See if the anti freeze is making the carbon on the tail pipe moist, or if maybe you have a bad water pump.

I hope this helps, but pattern failures are a bitch to guess at.

RK

The Doctor wrote in news:f235e08a-ea66-4d72-85ef- snipped-for-privacy@j38g2000yqa.googlegroups.com:

You have a failed head gasket. Sorry,but it's true.

But what does the sharp left turn/burning smell have to do with it? I've got no bubbles in the coolant, no milky oil and no smoke blowing out the tailpipe. I've driven cars w/blown head gaskets before and they've had all the above symptoms, in particular the smoke coming out of the tailpipe. My point is are you sure this is a head gasket? Thanks Jay

The Doctor wrote in news:505ce709-75ac-42b1-82ae- snipped-for-privacy@v13g2000vbb.googlegroups.com:

What side is your timing belt on? The passenger's side or the driver's side?

Hondas have a tendency to blow gases into the coolant when a gasket fails. If you've got "tremendous pressure" in the cooling system, you've either got a bad head gasket or an aftermarket water pump with a bad seal. Check the coolant for combustion gases with test strips, or have a garage do a pressure test using shop air fed into the spark plug holes.

Coolant squirting out the side of the engine onto the hot manifold.

I'm not sure but it would certainly be my first guess. I'm curious why the cap isn't venting it, though.

--scott

snipped-for-privacy@panix.com (Scott Dorsey) wrote in news:gkcr22$ei4$ snipped-for-privacy@panix2.panix.com:

That's a good point.

When the engine is cold, pull the cap off and have a look at it. Is it all gooped up on its underside? Can you push the gasket in on its spring with your fingers?

OK, I swapped out the rad. cap and still the same. I had to add close to 1 gal. of anti-freeze, too. Checked the rear tailpipe and other than some carbon build up-nothing. Then I chcked the oil again and its still very clean. Checked under the oil cap and its fine. I tried the sniff test on the oil and coolant but I can't seem to distingiush exhaust gases from anything else. Jay

If you are losing that much coolant, something is definitely out of whack.

Sniff test for CO2 in the coolant requires a test kit. You cant smell CO2 very quantitatively.

You could have a leak to the outside of the engine, via a head gasket or a Welch plug, or even a leaking hose or radiator. A leaking water pump could, conceivably, also squirt some coolant on your exhaust.

Normally, when coolant is leaking, you can find some evidence of it in the engine compartment. Colored stains, wetness, etc.

Let us know what you find.

OK, I'm taking it into my mechanic's shop tom'w to check for gases in the coolant. After that, if I don't find anything...its going on Craigslist! Jay

Actually, most cars will NOT mix coolant and oil when a head gasket blows, because there are either no or very few oil passages through the head gasket on most engines. The most common thing is exactly what you're seeing- combustion pressure getting into the cooling system. It has to be a pretty big leak for water to go the other way and (noticeably) get into the combustion chamber.

I suspect the head gasket like everyone else BUT I did have a car with a leaking heater water valve and I would smell the coolant "burning" when I parked and would have to add more coolant but could never find any leak. Finally after a couple weeks it leaked while I watched and pushed hoses around. I doubt you'll be that lucky though.

Mechanical flexing of a hairline crack in something, perhaps?

I wouldn't condemn a head gaskets (2.8 l V6 in those cars, right?) without actually doing the diagnostics and taking a careful look around. There should be some cosmetic evidence of just where pressurized coolant is coming out--especially if the engine was kinda dirty and greasy to begin with. It will scour the near vicinity clean and perhaps leave a bit of residue.

I think diagnosing it calls for a pressure test of the cooling system, then if necessary a compression test (several kinds of faults can be diagnosed by noting the pattern). I'd hate to see you commit to head gasket replacement if the problem is a cracked head or, yikes, cracked block... or do anything to engine internals if the problem is a cracked overflow tank or hose barb that only smiles at you when under pressure and stressed with a hard left turn.

Aside from being the "right" logical way to do things, this gives you information on whether the car should be repaired or sent into the trickle-down economy (no pun intended and not much of one achieved) with the smallest investment.

Best of luck, and let us know how it comes out, or stops coming out as the case may be.

--Joe