People with cooling problems - Read This
ericmf
06-09-2004, 10:54 PM
Hey guys,
A member of this website recently e-mailed me with problems from his cooling system. I had forgotton I was even signed up here, but since I feel anyones pain who has cooling problems I figured I would post the pointers I gave to him to all of you so the information does not goto waste. For the benefit of all please reply to the thread instead of PMing me. I've had quite a bit of trouble with my cooling system and have replaced almost every part outside the passages in the block and the heater core. So far I've invested almost $1,200, replacing the water pump, water pump belt, pulley and idler, radiator hoses, radaitor, and thermostat. Anyway here is our correspondance,
----Message from User----
I have a 95 Aurora and it over heats contantly like every day. I had the thermostat replaced and it still over heats I'm looking for help on this because I want to trade it in but dont want to trade it in like this I really want to fix the problem first. You see my water pump went out in the car in January and it cost me 1,200 to get fixed and they replaced my thermostat but I wasnt having problems with my tstat before the replacement it was actually fine at first but since the replacement its been running hot and 3 weeks ago I was going down the highway and it was fine until I got into some stop and go traffic and it completely shut down on me and I had to push it to the side of the road. I actually want to put my old tstat back in cause I asked for my old parts back when they repleaced my waterpump so please tell me what should I do?
----My reply-----
First, are you sure it is overheating? These cars run around 200 degrees and sometimes between the 200 and red area on the gauge in HEAVY traffic, I'm talking about traffic jams, not stop and go. If you have recieved the STOP ENGINE HOT message then you can be certain there is a problem.
I went through quite a bit getting my cooling system in order. I would first check out the radiator as this is a common problem on these cars. I am guessing that since you have a 95 you probably have more then 100,000 miles which is where the radiator failure commonly fails. It sounds shitty but 100k is actually pretty good for a radiator.
Anyhow take off the front clip, its black with air bag instructions on it. It is secured with 4 bolts upfront and 3 recessed on each side of it. When you goto pull it off pull back toward the hood, there is a little clamp that goes around the upper radiator hose, there is also another one you will have to push off, it looks like a giant plug w/ a strap around it, just pull on it toward the engine and it should break away.
Once you get that clip off start the engine and allow the car to get up to arond the 200 mark. Examine the top left of the radiator, (passangers side) look for small hairline cracks in the plastic housing that butts up against the aluminum core, if you see these or any excess build up of coolant on the outside of the radiator then there is your problem, you may also notice that there is alot of excess coolant on the back of the radiator directly behind the plastic housing that I just described, it will also be where the aluminum core clips around the plastic housing, this is a common place for leaks as well. Be aware that if your car has just recently started leaking you may not see any coolant on the ground yet. It takes a few weeks of build up in the pan that holds the radiator for it to overflow. This is a common problem causing these cars to overheat mysteriously because the car looses pressure in the cooling system. If this is the case then Message me again, I know where you can get a GM one for about $370, which is a steal considering the dealers want $700.00, if you are handy at all you can do this, it's not hard it just takes a little patience, If you are not good then buy a beer for a buddy who is good at it. I would not suggest replacing it with an aftermarket radiator, these cars are very picky and most aftermarket radiators require adapters that restrict coolant flow, this is a hot engine, I would not suggest changing the design much.
If you examine this and it does not help then ensure that all your hoses are good, if you don't see any leaks, make sure the car is at around 200 degrees or you may not see any leakage.
Next examine the thermostat housing, this is the area the upper radiator hose comes from, it is black and up against the water pump (metal/silver color) if you see no leaks there then make sure the water pump belt and idler pulley are working properly(driver side under a gaurd), they should be spinning straight with no sway side to side, the idler pulley may bounce a little, make sure it is spinning about 2/3's the speed of the the serpentine belt on the passengers side. If it seems excessively slow then your water pump or idler pulley is still having some issues. Also make sure that it is not making any noise.
If you find nothing, try flushing the cooling system, You can pick up a flush kit at walmart for around $3, you will also need some radiator flush (a cleaner $3-5) and some coolant(I use prestone, you'll need two bottles they are about $6). You will also need some distilled water, you can get this at and all the other parts at a local walmart, the water should cost you a dollar or two. (DO NOT GET SPRING WATER, you can use regular tap water to flush the system but when filling it I would spend the dollar or so and use good quality water for your 50/50 mixture.) Once again if you are not handy with a car a buddy should be able to help you here. If you decide to flush then message me. I'll give you some pointers.
Last try replacing your thermostat with a good one, some dealers and shops use cheap ones believe it or not it can make a huge difference in the summer. I use STANT 54MM thermostats, you can pick one up at Advancedauto Parts (Partsamerica.com) for around $15.
If none of these answers solve you problem then you could have an internal clog in your block passages or in the heater core, unfortunately I have not had to replace either of these parts and I've never heard of one failing in these vehicles. If you do come to this conclusion I might be able to get you some directions for replacement from my shop manual.
I hope this helps you,
Thanks and good luck,
Eric
PS. Keep the car, if this is all thats wrong, they're smooth rides...
A member of this website recently e-mailed me with problems from his cooling system. I had forgotton I was even signed up here, but since I feel anyones pain who has cooling problems I figured I would post the pointers I gave to him to all of you so the information does not goto waste. For the benefit of all please reply to the thread instead of PMing me. I've had quite a bit of trouble with my cooling system and have replaced almost every part outside the passages in the block and the heater core. So far I've invested almost $1,200, replacing the water pump, water pump belt, pulley and idler, radiator hoses, radaitor, and thermostat. Anyway here is our correspondance,
----Message from User----
I have a 95 Aurora and it over heats contantly like every day. I had the thermostat replaced and it still over heats I'm looking for help on this because I want to trade it in but dont want to trade it in like this I really want to fix the problem first. You see my water pump went out in the car in January and it cost me 1,200 to get fixed and they replaced my thermostat but I wasnt having problems with my tstat before the replacement it was actually fine at first but since the replacement its been running hot and 3 weeks ago I was going down the highway and it was fine until I got into some stop and go traffic and it completely shut down on me and I had to push it to the side of the road. I actually want to put my old tstat back in cause I asked for my old parts back when they repleaced my waterpump so please tell me what should I do?
----My reply-----
First, are you sure it is overheating? These cars run around 200 degrees and sometimes between the 200 and red area on the gauge in HEAVY traffic, I'm talking about traffic jams, not stop and go. If you have recieved the STOP ENGINE HOT message then you can be certain there is a problem.
I went through quite a bit getting my cooling system in order. I would first check out the radiator as this is a common problem on these cars. I am guessing that since you have a 95 you probably have more then 100,000 miles which is where the radiator failure commonly fails. It sounds shitty but 100k is actually pretty good for a radiator.
Anyhow take off the front clip, its black with air bag instructions on it. It is secured with 4 bolts upfront and 3 recessed on each side of it. When you goto pull it off pull back toward the hood, there is a little clamp that goes around the upper radiator hose, there is also another one you will have to push off, it looks like a giant plug w/ a strap around it, just pull on it toward the engine and it should break away.
Once you get that clip off start the engine and allow the car to get up to arond the 200 mark. Examine the top left of the radiator, (passangers side) look for small hairline cracks in the plastic housing that butts up against the aluminum core, if you see these or any excess build up of coolant on the outside of the radiator then there is your problem, you may also notice that there is alot of excess coolant on the back of the radiator directly behind the plastic housing that I just described, it will also be where the aluminum core clips around the plastic housing, this is a common place for leaks as well. Be aware that if your car has just recently started leaking you may not see any coolant on the ground yet. It takes a few weeks of build up in the pan that holds the radiator for it to overflow. This is a common problem causing these cars to overheat mysteriously because the car looses pressure in the cooling system. If this is the case then Message me again, I know where you can get a GM one for about $370, which is a steal considering the dealers want $700.00, if you are handy at all you can do this, it's not hard it just takes a little patience, If you are not good then buy a beer for a buddy who is good at it. I would not suggest replacing it with an aftermarket radiator, these cars are very picky and most aftermarket radiators require adapters that restrict coolant flow, this is a hot engine, I would not suggest changing the design much.
If you examine this and it does not help then ensure that all your hoses are good, if you don't see any leaks, make sure the car is at around 200 degrees or you may not see any leakage.
Next examine the thermostat housing, this is the area the upper radiator hose comes from, it is black and up against the water pump (metal/silver color) if you see no leaks there then make sure the water pump belt and idler pulley are working properly(driver side under a gaurd), they should be spinning straight with no sway side to side, the idler pulley may bounce a little, make sure it is spinning about 2/3's the speed of the the serpentine belt on the passengers side. If it seems excessively slow then your water pump or idler pulley is still having some issues. Also make sure that it is not making any noise.
If you find nothing, try flushing the cooling system, You can pick up a flush kit at walmart for around $3, you will also need some radiator flush (a cleaner $3-5) and some coolant(I use prestone, you'll need two bottles they are about $6). You will also need some distilled water, you can get this at and all the other parts at a local walmart, the water should cost you a dollar or two. (DO NOT GET SPRING WATER, you can use regular tap water to flush the system but when filling it I would spend the dollar or so and use good quality water for your 50/50 mixture.) Once again if you are not handy with a car a buddy should be able to help you here. If you decide to flush then message me. I'll give you some pointers.
Last try replacing your thermostat with a good one, some dealers and shops use cheap ones believe it or not it can make a huge difference in the summer. I use STANT 54MM thermostats, you can pick one up at Advancedauto Parts (Partsamerica.com) for around $15.
If none of these answers solve you problem then you could have an internal clog in your block passages or in the heater core, unfortunately I have not had to replace either of these parts and I've never heard of one failing in these vehicles. If you do come to this conclusion I might be able to get you some directions for replacement from my shop manual.
I hope this helps you,
Thanks and good luck,
Eric
PS. Keep the car, if this is all thats wrong, they're smooth rides...
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