I just got my car back from the body shop and I was driving around today when I noticed the temperature gauge pegged at 260. I wasn't close to home so I didn't really have an opportunity to stop and let it cool down. Just as I managed to get my car in my friend's garage, I popped the hood and noticed steam pouring from the plastic coolant bottle. About 30 seconds later massive amounts of steam literally shot out of the radiator cap, drenching my engine in the green stuff. I haven't inspected the radiator yet for cracks, I'm guessing that there's some kind of safety-release valve on that cap that got tripped. Right now I'm letting it cool down by itself and I'm going to do a coolant change and flush as soon as it's cooled down. What kind of long-term effects can I see from this overheating? I was driving for about an hour with the needle pegged at 260 (stupid me, I know I should have stopped).

 

Long term, possibly a warped head(s). Melted wires. Your best bet is to get the coolant squared away and watch what it does.

 

Well, I kinda had the same problem. I was driving on 94 and my temp gauge went to 220. The outside temp was 82*. I have a 160* stat with (4) .200" holes. My temp on the hwy has always ran around outside temp + 100*. If its 80* out my coolent temp will be around 180*. I don't know why it dose this but it dose. I checked the air deflector and with very little effort could move it towards the rear. So I said to myself "What position is the air deflector in at 70, 80 ect MPH" Well I bought a new one from a chev dealer for $18. Heck it was 18 years old. Went for a ride and eng. temp was at 210* Helped some but no cigar. So I said to myself, self, start with the basic and easy stuff. I gave the rad. cap a visual and it looked ok. Checked all belts and replaced the waterpump, alt. belt. $12 at NAPA. Removed the stat and suspended it in a pan of water and turned the burner on high. Never opened! The only thing that kept the eng. from cooking was the (4) .200 holes drilled in the stat. Whew!!! Bought a new stat (160*)( $10 I bought the most expensive one they had) and checked it out on the stove. New stat started to open at 150* and was fully open at 160*. Went for a test ride. Its 76* out and eng. temp gauge reads just under the mark between 100 & 220*. That mark equals 180*. Done.

Auggie

 

Thanks for the info, guys. Upon checking the radiator, it turns out that the entire side of the thing split due to the pressure. I bought a new radiator, 180° thermostat, and radiator cap and put it in today along with a 50/50 mix of coolant. So far it seems to work but I'll have to see over the long-term. I've determined that the car overheated because the fan never came on -- the fan housing was warped and the motor burned itself up... I drove home from the friend's house without the fan, but I'm definitely going to get a new one before I drive my car regularly again.

I'll have to think about getting a new air deflector... for only twenty bucks I'd rather have a new part anyway.

 

Yea, My car use to run at 180 but a little while back, an 18 wheeler tire came apart infront of me on I-85 in Atlanta. I had three choices hit the wall, hit the car beside me, or hit the tire. So I hit the tire. Anways it went under me luckly not over, it tore most of my air deflector off and my dust shild on my transmission was cracked. Now my car runs about 215 down the highway. ouch I really need to get it fixed. I have a radiator that is 2 years old so its in good shape. THe only other time its gotton up to 220 is when I had a newspaper get stuck in the airdam that I didn't know about, but as soon as it got up to 220 I pulled over, looked up under the car and it was covering about 4/5 the radiator.

5.0 '89 formula

 

heh a little off subject but talking about blown radiators? Has anyone even blown a radiator in forklift? It's hilarious! Maybe they'll finally get a new one at work now? :rockon: :rockon: :rockon: :rockon: :rockon:

 

why would you pull over at 220*.., 220 isnt overheating.., mineoverheats ALOT..., but its because the fan does not work, i need a new o2 sensor, MAF sensor i think, ot something like that, and a new engine temp. sensor...., if it still doesnt work then im going to check the fanmotor.., it recently got a brand new fan, fan switches and fan relays

 

A few days ago I went to a junkyard and picked up a pair of dual fans from an '89 IROC for $100. I got two thermal fan switches, per Willie's excellent tech article on F-body cooling fans. So far, I haven't gone past 220... the first one kicks on at 180° and the other one turns on at about 195°.

 

I pulled over because it was winter and about 40 degrees outside and it was still going up. And I knew it would keep going up. My car never gets that hot in the winter, and normally not that hot in the summer.

 

Pete86iroc

were you having problems with your fans coming on or burning up motors when you replaced the relays? I just put in two new fan motors because my fan motors burned out. I tested them by jumping the relay for one and key-on for the other. They worked fine, but the next when i started the car the didn't work any more.

btw, does anyone else's fan come on when the key the ignition on?

 

Im having problems getting the fans to turn on.., the motors fine.., im just going to instal a manual fan switch instead of replacing the sensors

 

The fan should only come on with the ignition key if the coolant temperature exceeds the fan turn-on temperature, or the A & B terminals on the ALDL connector are jumped.

 

I think I found my problem. I have a bad wire near the battery that provides power to the fans. They weren't coming on when they were supposed to and when I jumped the relay, the one came on sporadically. Bypassing this wire with a new one putting power the fans, they work now.

One of my fans (passenger side, secondary?) comes on when the I key on (once I fix the bad wire). could the fan switch be bad?

pete86iroc

try running temporary wires to the relay for the power, etc and see if that helps. If you jump the relay do the fans come on?

 

last night i was coming home from work and i noticed the temp gauge was reading close to the danger zone. when i got home i popped the hood i heard a hissing from the radiator. so i looked around and seen the bubbles come from the side of the radiator. is there another way to fix this other than buying a new radiator. if not about how much will a new one cost me.

 

It might be shorted out... if you had any electrical problems it could have burned up the switch or the relay. That happened to me when my single fan's motor burned up. I would suggest reading the article on coolant fans in the tech articles section of this site. Get yourself some nice aftermarket thermal fan switches -- not only will you be able to have the fans turn on sooner, but you'll know that the wiring is correct if you did it yourself.

If the plastic end-cap is cracked, you might want to see if you can get a radiator shop to put new end-caps on (probably about $60). If you don't have time for that, just do what I did and buy a new radiator. I got mine from Advance Auto Parts for $105.