Bad thermostat changed to blown head gasket? Need help!!!

[Sushibandito]

Edit: This is in the wrong section by mistake...

Didn't seem to be much for my particular problem, and its rather complicated, so hoping that someone has some advice...

I have a stock KA24DE with an auto transmission, 105k miles.

2-3 weeks ago my temp gauge went up to 1 bar short of High on a rather short drive to the grocery store. Parked the car, did my shopping, on the ride home temp gauge stayed at center. Didn't happen again for weeks.

2 days ago it went to High several times, so bought a new thermostat and swapped that out today. Bled the system correctly after figuring out where the bleeder screw was, was fairly certain that I got all the air out, although the temp gauge never left the bottom, stayed cold the entire time, even after 20 minutes. This is after at least an hour of the car being on jack-stands with the radiator cap off.

1st issue - The exhaust is pumping out a fair amount of white smoke that smells sweet, definitely coolant. 2nd issue - Some squealing on acceleration that has never been there before, and I didn't remove any belts to get the thermostat out. This may be entirely un-related, but not sure if it is somehow connected.3rd issue - The water pump is leaking tons of coolant, not sure if that is due to a gasket that went bad from pressurizing the cooling system without having first removed the bleeder screw?

Since I was working on the car at my brothers, on the drive home it stopped blowing coolant and the temp gauge reached normal, but I suspect that has more to do with the radiator burning through all its reserves. Will be checking fluid levels tomorrow morning. I also just changed the oil today to Mobil 1 synthetic, and I have heard rumors of this being a bad idea on an older car?

[berman]

sounds like head gasket. run the car with radiator cap off look for bubbles. water pump is leaking then its bad. you can also test the thermostat you bought to see if it is working right. pull it out find the temp spec on it probly around 165 or something i donno the spec is. if you put it in water at the temp spec it should open. the smell of coolant coming out the exhaust sounds to me like head gasket not uncommon when car has overheated. hows the oil look?

[Sushibandito]

My brother is convinced I should replace the water pump then just buy this head gasket sealant that GM developed when (unconfirmed) some of their models were having serious issues with blown head gaskets. But I tend to err on the side of having a fully functional engine, and I can't afford an SR for a while.

I would figure the car has to fully over-heat for the head gasket to blow, and the car never hit the highest point on the temp gauge, but then again, I am sure its not the strongest after 18 years. Oil looks fine, I haven't drained it as its brand new Mobil 1, I checked under the oil filler cap and dipstick, solid light brown, no white foam to be found.

And its lots of white smoke with a coolant odor, but it doesn't smell like its mixed with an oil smell, but from what I have read, both coolant and oil burn white.

My shop guy who exclusively does Nissans and Datsuns, mostly drifter cars, is gonna give it the run down next week, labor is quoted at $500 plus about $150 for new water pump+gasket+Machine work. I should be doing this myself, but as its 30 degrees and I have managed to screw up other simple projects while following instructions, this might be better left to a professional.

[berman]

im not a fan of head gasket sealants and other stuff like that doesnt usualy work and if it does it only a temp fix. there is only 3 reasons for coolant to be coming out the exhaust: head gasket, cracked block or head. and oil usualy burns blue.

[Sushibandito]

The only temporary thing in my car is the 3 bolts holding down my Sparco's, I am willing to skimp on things that won't affect its reliability, but not when it comes to the engine.

I am hoping to FSM (Flying Spaghetti Monster) that the head or block isn't cracked, since trying to track down a decent KA24 for a swap seems tough when they are all so old, and finding one with decent mileage would be tough...

[OutToWinPAHC]

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