Overheating

Cottonfarmer · 09-04-2006, 10:28 PM

About a month ago I responded to a post (can't remember who it was that started the thread) about a fellow's GTO overheating and boiling out the water. Mine did the same thing but didn't lose any coolant. Well about a week ago, the wife was driving and mentioned that the car did it again but quickly cooled itself off after she started moving. Tonight I take the car to the service station for a tank of gas and it did it to me. The temp gauge went all the way to the last red mark. I shut it down for about five minutes and restarted. It had dropped back a bit and I expected it to return to normal but it instead started climbing up the hot mark again. This time I shut it down and waited about 15 minutes and restarted it. I had about a mile drive back to the house and while going down the road, I noticed the temp gauge started making some rapid excursions up and then down but never getting to the hot mark. After I got home, I checked the coolant level and saw that it was down a small bit. I added about a gallon of water, which actually overfilled it a bit.

When this happened the first time to the wife, I assumed that the fans weren't kicking it on time. After tonight I find that is not the case as the fans start kicking in very soon after the temp gauge passes the middle mark on the scale. I also noticed a bit of "hot" coolant smell when this happened to me tonight so without a doubt the temp is actually getting up there.

Now my diagonsis is that the thermostat is sticking and if anyone has any other ideas I would be most appreciative to hear them. Tomorrow the Goat goes off to the dealer for a thermostat replacement at my demand unless someone else on the forum has another theory.

Thank goodness no appreciable coolant loss was experienced so I'm not concerned about any engine damage. This problem has the potential of destroying an engine if not attended to.

Thanks for any replies. -Jim

burnz · 09-04-2006, 10:50 PM

I'd think it's more than just the thermostat. I don't know how they wired the temp. sens. on the gto, but my other cars fans wouldn't turn on intill the temp. in the radiator hits it's over the switch temp. any time I had a bad therm. it would just hold the water in the block and over heat that. good luck.

burnz · 09-04-2006, 10:54 PM

sorry didn't see at first that the fans are turning on, then yes the the therm. can be sticking in the open spot. whitch dosn't give the radaitor time to cool down the coolant.

Cottonfarmer · 09-04-2006, 11:09 PM

Quote:

Originally Posted by burnz

sorry didn't see at first that the fans are turning on, then yes the the therm. can be sticking in the open spot. whitch dosn't give the radaitor time to cool down the coolant.

Most likely the thermostat is sticking in the closed position. When closed, the coolant is recirculated in the engine block and not allowed to flow through the radiator for cooling. A properly working thermostat "modulates" the flow of water through the radiator so as to maintain a more or less constant coolant temperature in the block.

Another thought occured to me. Years ago I had a tractor on the farm I manage do much the same thing. What happened in this case was that the impeller of the water pump had begun slipping on the water pump shaft. The impeller was supposed to be a press fit to the shaft but I guess in this case the hole machined into the impeller was a tad too large for the press fit to hold the shaft and impeller solidly together. Anyway, I will go over all this with the dealer tomorrow and hopefully we can arrive at the solution. -Jim

burnz · 09-05-2006, 07:22 AM

If you can, post what the out come was. I know when I took out the therm. in my firebird it would over heat, they gave me the wrong one. so I left it out. once I put the new one I she was fine. had a buick centry that the therm. started to stick the fans wouldn't turn on and you could watch the temp. gauge drop evey time the them. opened. ether way good luck.

fenderbirdbass · 09-06-2006, 04:28 PM

That was me who was overheating and it was the thermostat.Get it changed and you will be fine.My car was doing the same thing.

Cottonfarmer · 09-06-2006, 09:13 PM

Quote:

Originally Posted by burnz

If you can, post what the out come was. I know when I took out the therm. in my firebird it would over heat, they gave me the wrong one. so I left it out. once I put the new one I she was fine. had a buick centry that the therm. started to stick the fans wouldn't turn on and you could watch the temp. gauge drop evey time the them. opened. ether way good luck.

Right now I have such a red ass about my dealer I can't see straight because my blood pressure has my eyes bulging.

Yesterday morning the wife took the car to work. She had to stop THREE times in order to let the car cool off. After telling me this, I left my job and went to get the car to take to the dealership. In about a three mile drive to the dealership, I had to stop one time to let it cool off. At the dealership, it was starting to heat up again and the service manager witnessed it doing this. I left the car thinking they would fix my problem but when I got the call to pick it up, I asked what they did. They reponded that their "technician" couldn't find anything wrong with the car mechanically and simply washed the bugs out of the radiator. He said that fixed the problem.

Now after I told him AGAIN the full history of the symptoms he still said that the radiator was plugged with bug guts. I replied, "How in the hell could a plugged up radiator make an engine run hot and then all the sudden let it cool off and then how could that car be driven 3000 miles with no heating problems in near 100 degree heat and then the so called plugged radiator all of the sudden make it run hot again after that extended period". He still stuck with his story.

By this time my blood is boiling. I told him in my experience of over 40 something years of working on a farm around tractors, trucks, power units and other machinery his explanation was nothing but bull hockey. I told him they had NOT fixed the car and that the thermostat needs to be replaced. He responded that they could not simply "throw" parts at a problem like that. Dang, now that was a brilliant answer! Anyone with any mechanical ability would know that a sticking thermostat is one of the most likely causes of my complaint and THAT is one of the first things to investigate. They refuse to change the thermostat.

I told the service manger then that what he was trying to get me to do was to take my car home with a known heating problem that hasn't been fixed, drive the car and potentially destroy a very expensive engine all because of a $20 thermostat that they refuse to replace. That is utter insanity in my opinion. He still said it is fixed.

Incidently while the wife came in from work today, the car started to overheat again but fortunately didn't get too hot before it started cooling off again. Now if I was the a**hole the dealer thinks I am, I should just let the temp go the next time and fry the engine. Then I would write a letter to GM telling them the full story and let the dealership explain to GM why they have to replace a multi-thousand dollar engine on warrenty all because of a $20 thermostat the dealer refused to replace.

On a side note I told the service manager their use of the word "technician" is misleading. In every shop I ever been around, there usually are one or two folks working in the back who genuinely know what they are doing and the rest of the crew are, on the whole, ignorant on how to diagnose and repair a modern automobile with all it's technical sophistication. A technician, by my definition, knows all aspects of his job and knows how to solve problems using his own skills and knowledge. I don't think attending a service seminar a couple of times qualifies anyone as a technician. Whatever happened to the term "mechanic"?

Anyway, I don't think the service manager a Jim Taylor Chevrolet in Rayville, LA likes me any more. Be assured that doesn't bother me much.

I will keep you guys informed on how this washes out. -Jim

burnz · 09-06-2006, 09:32 PM

.
sorry to here that. that sucks, a good sevice dept. is hard to find. I bought my gto at a differant place that I get it worked at. love the sevice but the sales sucks. the other way around for the place I got the gto. well good luck hope it gets worked out, but it will still smell like sh** even if they pick it up.

]

6QTS11OZ · 09-06-2006, 10:45 PM

Also, whatever happened to test driving a vehicle?

arch&69 · 09-06-2006, 11:20 PM

Man that really sux.

I really can't help you, but if anyone has any problems with their dealer in the phx, az area, go to Brown and Brown Chevrolet, talk to Bruce Archuleta (a service advisor), and tell him that "the kid with the blue 69 GTO sent you". He'll know who you're talking about. He gets things handled right the first time. He used to work over at Tony Coury Buick, and was offered the job at B&B, he left and coincidentally, he took all of his customers with him. Not to mention the guys at B&B are really knowledgeable. I promise, you will never have any problems ever again.

They do a lot of work on older cars too. I got my paintjob there, and had one of the guys helping me to get the engine running again when it caught on fire. Right now, there is a Red 69 GTO, and just yesterday, a guy with a white and black 1970 Yenko Chevelle came in for some suspension work. By the way, that car is worth more than 400,000 smakaroos. I'd say, if he trusts them, you and your 40k car can trust them.