Blown Head Gasket... WHY???

[Andre the Giant]

OK, I'm looking for a few theories to explain this.

My '92 T-bird 3.8L V-6 (120,000 miles) has been running goofy for a few months now. It runs rough as long as the engine is cold, and the engine takes a long time to warm up. There was a small Anti-freeze leak from the water pump but I always kept the fluid levels up and always checked the temp gage to make sure the engine wasn't overheating.

Friday I replaced the Waterpump and the thermostat. I fill the engine and radiator with coolant, and I fire the thing up, it runs very rough. I shut it down and check the fluids again, everything is tip top the water pump is pumping, so I test drive it for a while. The engine never warms up. I checked to see if I somehow got the thermostat in backwards or something, but everything was hooked up correctly.

Tuesday I drive the car to work, same deal. The car never warms up and it runs rough. When I go home for lunch, and shut the engine off, I hear a hiss from the engine. I check the Vac hoses, nothing wrong, start it again. Now it's missing on one cylinder. I shut it down after 20 seconds or so, and I hear the same hiss. I think "Blown head gasket?!?" So I look around the back at the tailpipe... There's a nice puddle of Antifreeze dripping from the Muffler drain hole. WTF?!? Did I do something wrong???

Any theories on what could have happened?

Thanks

[Polygon]

Yes you may have a blown head gasket, you may also have a cracked head or engine block. The latter two are usually caused by a blown head gasket and exuast gets into the engine and it heats up and crackes the head, block, or both.

Have it towed to the nearest dealership, DO NOT START IT. Have them check it out to see, but I would say that the head gasket is gone for sure, and one or both are craked as fluid is getting into the engine and going through the exaust.

[Andre the Giant]

Sorry I confused you but, I already know what the problems may be, and once I saw the anti-freeze/tailpipe, I did not crank it again, and had it towed to the dealership. I was just trying to figure out if I did something that caused the gasket/head to let go.

Maybe the head gasket was already damaged and leaking, but because the water pump wasn't working at 100%, it just caused rough idling, then, the increased pressure of the new/properly functioning water pump caused the gasket to give way completely. I still can't figure out why the engine wouldn't warm up though.

[Polygon]

I am not sure what may have caused the head gasket to go. As for the car not warming up and running rough. That is caused by the coolant and water in the engine.

[Moppie]

The same engine was used on the Holden Comodore over here, and I know earlier ones suffered from blown head gaskets as they got older, so it could simply be the new water pump was to much for it. (assumeing the old one was pretty sutffed)

However another possiblity: Did you bleed all the air out of the system after refilling it?

[CraigFL]

There is a situation that some cars have--- If you get an airlock in the coolant system or if the coolant is low, the temperature sensor doesn't stay immersed in the coolant/water mixture so your temp gauge never registers the overheat condition. Your head warps and the gasket blows (among other things).

Ask me how I know!!

[Andre the Giant]

I thought about it and its possible that some air was in the cooling system. I didn't bleed the air out of the system. No matter what, its not going to be pretty in there. I am going to pull the heads and replace the gaskets myself, so I'll be sure to have someone check the heads and make sure they aren't TOAST. I'm contemplating a complete engine rebuild, but don't know if it's necessary. Any ideas?



"Merry Christmas honey... I blew up my car. Can I borrow yours?"

[Polygon]

When you take the head off look for cracks aroung the valves that is where they usually are, also check the block. If you are really seriouse I would say just replace the block and head. Should only cost around two maybe three grand for your car. If just the head is craked then I would only replace the head.

[Andre the Giant]

T-bird Update!

After a hectic month of holidays and whatnot, I finally got the heads off my car. The block and heads are in good shape. The drivers side head gasket had deteriorated between the waterjacket and the #4 (front) cylinder. The metal part of the head gasket (the part that rings the cylinder bore) was slightly deformed allowing coolant to pour into the cylinder. The other cylinders showed typical carbon deposits while the #4 cylinder was clean and shiny. I wonder how long this has been a problem.

Anyhow, the heads show no sign of warpage or overheating. I guess the new healthy waterpump I installed had more pressure and blew more coolant into the cylinder. It coulda been much worse. I think I'll have a valve job done on the heads just for fun.

Andre

[texan]

Sorry I'm late on this one...

The Ford Essex 3.8L V6 is notorious for blowing head gaskets, I blew both of them on my old Mustang in about 90k miles. There aren't enough bolts to hold the head down for one, and the farthest forward and rearward water jackets on each bank are too close to the cylinder bores (I blew the rear ones on each bank). So don't go beating yourself up over it, this is par for the course on a Ford 3.8L motor.

[GTStang]

I'd check to make sure your water temp gauge is working!!! Also spend the $50 it will cost to have your heads pressue checked at a machine shop