Overheating

**asshanson** · 10-27-2007

First off, completely stock 7 bolt motor on my 96 talon. No ARP headstuds or anything, the engine head probably hasn't been off the car even. I recently put on a 20g turbo, but everything has been going pretty well since then, no huge problems. At the dyno day it was blowing smoke after each run, not sure if it was gray or white smoke, but I figured it was because it was running super rich, way less than 10/1.

My car was running fine until yesterday, when out of nowhere it's running way too hot. Since I put on the new turbo I've only floored it in 1st gear a few times, but several 2nd and 3rd gear pulls. Yesterday after work I decided to have fun at WOT for 1st through 3rd gears. 5 minutes later the temp guage was pegged at hot and all the coolant is bubbling and overflowing. I had a gallon of water in the trunk and waited for it to cool off, refilled it, and started driving again. The temps just kept rising, and it would cool off a little when idling. Even going 40mph in 5th gear it overheats, but not at idle, just any little amount of load.

So I thought I blew a headgasket and starting checking things today. There are no obvious coolant leaks, at least nothing is dripping out coolant all over the ground, nothing that would make it overheat in 5 miles of driving. I did a compression test, results are something like 170, 175, 190, 190, and the tops of the pistons looked dry. It's about a quart low on oil, I was just going to change it this weekend. It's also been using a little coolant since I got the car, but nothing really unusual, I just have to put more in the resovoir every 6 months.

I also checked the pully for the water pump, it's not loose or anything, and all the belts seem to be in place with good tension, nothing is slipping. I haven't checked if anything is wrong with the heater core yet.

Any suggestions on other things to check tomorrow? I'm out of ideas, and I dont know how to do a leak down test. I'm stuck in Des Moines, so I can't take it to any of the shops up there. I have almost all my tools here though so I can do quite a bit, but a headgasket may be tricky here since I've never done one.

FattyBoomBatty · 10-27-2007

Well, the weird compression numbers could be an indicator, but you could also have a faulty thermostat. Pop that guy off and put it in a pan of water on the stove, heat it up, check the temp of the water when it opens. Or, if could be completely broken, I had that happen once, but it would never heat up. so, I dunno. Running super rich could also have something to do with that, though I think if timing was way off that would cause more of a problme, and i bet that has nothing to do with it.

good luck.

**JET** · 10-27-2007

My first guess would be a blown HG. It sounds a lot like it. Bad radiator cap would also cause it, as would a bad water pump. I had a car with a bad head gasket give similar readings to yours, it was a bit low in #2, but not much. When I pulled it off it was obvious though. Take the car for a short drive and be really nice to it, bring it back and see if the coolant is bubbling out.

You can also check the water pump by pulling out the T-stat and leaving the coolant a little low. Start the car from cold and see if the coolant is moving by. The water pumps in our cars are usually really good and start leaking if they have a problem.

blageo23 · 10-27-2007

My car was bubbling out once and everyone said it was the HG. I changed the rad cap and it was perfect. Another thing to check if its the HG is start the car and feel the upper rad hose. If it get really stiff after only a min or so then its most likely that the cylinder is shoving some of the compressed air into the system. If you have a cylinder leak tester that is the best way to check the HG.

dragonforce · 10-28-2007

Sounds like you have a combustion leak.

turbotalon1g · 10-28-2007

test teh cap, sounds like you could of lifted the head.
Also filling a DSM with coolant when its already at running temp is a good way to kill it, i hope u put it in the overflow.

blageo23 · 10-28-2007

he said he waited for it to cool down.

turbotalon1g · 10-28-2007

^so a couple of hours then?
Cause dsms get cold within about an hour right.

blageo23 · 10-28-2007

Mine gets ice cold in like 10 min. Doent yours? If not I think you have a problem. I mean cast iron disapates heat really well and all.

But I guess cooled down to me is different then cooled down to others.

**asshanson** · 10-28-2007

I didn't want to take off the radiator cap when it was hot, I filled the overflow bottle after 20 minutes or so. Never tried to take the cap off since I was afraid it would explode off. By the way, why would this kill the car?

Anyway, took off the upper radiator hose and couldn't find the thermostat, maybe the previous owner took it off? Where is it at on a 2g? Here are some pics, looks like there is a decent amount of gray RTV on both surfaces. So should I put it back together with a gasket and make sure the water is flowing? I'm really a noob to all of this, any help is greatly appreciated.

Oh, I just did another compression test, this time with the motor completely cold, and it was 160, 180, 180, 190.

**scheides** · 10-28-2007

Do you stall have all of your stock radiator fans in the car? Not sure they fit with that turbo. Remember I said to put heat shields to cover the turbine housing and o2 housing?

**asshanson** · 10-28-2007

Stock fans are still there, and they work. I also never had the heat shields for the o2 or lower exhaust areas. It was running just fine, even a trip down to iowa it never overheated. Now in 10 minutes of regular driving it overheats, something definitely broke.

Edit: I put the radiator hose piece back on and started it, I had the cap off and I could see coolant flow into the tube and it looked it like was flowing back and forth a little bit, so I guess it looks like the water pump is working fine??

turbotalon1g · 10-28-2007

Quote:

Originally Posted by blageo23

Mine gets ice cold in like 10 min. Doent yours? If not I think you have a problem. I mean cast iron disapates heat really well and all.

But I guess cooled down to me is different then cooled down to others.

i THINK you have a problem, All 4 of my DSMs have been the same and my cars usually run great.

Slowboy, if you are up for it, ceramic coating works badass for underhood temps.
Check out formandfunctionperformance.com
Tell bob that i sent you.
ITs worth every penny.

**asshanson** · 10-28-2007

Alright, took it out for a drive, and had my girlfriend drive behind me. She said there was a lot of white smoke coming out while accelerating, and the car was somewhat warm, but not over 200. So we switched spots and she drove back home while I followed, she didn't get on it very much at all but I could still see some white/light-gray smoke coming out under any moderate acceleration. It's mostly water in there for coolant right now, so it didn't smell like antifreeze. It was different than at the dyno day, there all the smoke came out after the pull was done, this time it was during acceleration.

Temps still weren't up to normal, so we drove out to the BP a couple miles away. On the way there it didn't get above 220, but I was being really conservative, no boost at all, and had the heat full blast. On the way back it stayed the same until I turned off the heat and had to go up a hill. Then it immediately went to 140 or something, so I turned the heat back on, coasted down the hill back home and it went back down to 130. Overflow bottle was pretty full, but not overflowing, and not all bubbly.

So I'm pretty sure it's a headgasket, now I have to figure out how to fix it.

A//// Guy · 10-28-2007

Yea it sounds like a blown HG from all the symptons and having no obvious leaks.

Have Enes tow it back up here maybe?

Swifty1638 · 10-28-2007

bring it back up here. I'm sure one of us can do it for ya.

-A. Swift

**Goat Blower** · 10-28-2007

**Kracka** · 10-28-2007

Yup sounds like a headgasket to me too. That would be a mighty long and expensive tow, you might be better off having a shop down there take care of it for you.

This really isn't too surprising considering you're running more boost than ever before and you're still on the stock headgasket and studs after 125k miles.

95talonracer · 10-28-2007

The thermostat is under the pipe below the one you removed not that one. Sounds like a HG to me as well. Try checking to see if your thermostat works with the hot water trick and see what happens as well but that wouldnt explain the smoke.

**JET** · 10-28-2007

A HG really isn't a huge task if you have a garage. I would put some ARP studs in while you are in there, if anyone down there has any. I was scared to do my first one, but after i was done it wasn't as bad as I thought it would be.