Car overheating

[pippo]

People,
1987 sunbird GT non turbo, thermostat removed, AC on with the heat of the summer, driving 60 mph on the highway. Car's temp guage shows almost at halfway mark to red zone, which in our cars is bad news. Normally, a short drive to work temp guage is at say, 7:30 position, which is good. But at 60 mph for say, 20 minutes, temp reaches a scary 8:30 position, which , on our guages , is almost 1/2 way toward the red zone.

I know with ac on, and the condenser producing heat right in front of the radiator fan, engine will not cool as good as if ac would be OFF. Any ideas to help this situation?

Thanks, people.

 

[melsg5]

Does engine fan come on?
When fully cold, coolant is at proper level?
Nothing blocking radiator or AC condenser?

 

[92 Sunbird LE]

Add some of this and report back...

Doug in P.R.

 

[pippo]

Does engine fan come on?
When fully cold, coolant is at proper level?
Nothing blocking radiator or AC condenser?

You know about our cars- fan only comes on when it is in the RED zone- by that time, thew engine is destroyed, so I toggle switch my fan to ON way sooner. Coolant reservoir is wierd- I top it off, and it goes down to almost empty, retaining about only 1/2" of coolant. Then I top it off again, and same thing happens. But it never goes 100% dry/used up. But i am not burning coolant as I do not get white exhaust. Nothing is blocking the rad/condenser.

______________________________

 

[pippo]

Add some of this and report back...

Doug in P.R.

have you tried this Doug? Does it really work or is it just another elixir/snake oil product? I am willing to try it!!

 

[melsg5]

You know about our cars- fan only comes on when it is in the RED zone- by that time, thew engine is destroyed, so I toggle switch my fan to ON way sooner. Coolant reservoir is wierd- I top it off, and it goes down to almost empty, retaining about only 1/2" of coolant. Then I top it off again, and same thing happens. But it never goes 100% dry/used up. But i am not burning coolant as I do not get white exhaust. Nothing is blocking the rad/condenser.

You have a leak.

 

[92 Sunbird LE]

Used it ( another brand )in Arizona on my drag Monza with a Cadillac 425, never overheated or got hot even when racing in triple digits with just water ... That's with a smaller aluminum radiator then stock...some people add 2 bottles if they need to drop more...

Might be time for an all aluminum radiator or block/ radiator flush if it doesn't help....mine disappears also...."evaporates " due to the higher heat here but in winter cooler months it doesn't. , I run water and rust preventor .....no coolant in mine currently..

Doug in P.R.

 

[92 Sunbird LE]

This is the one I used, about 4 different brands are available...all do the same thing.....

Doug in P.R.

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[melsg5]

This is the one I used, about 4 different brands are available...all do the same thing.....

Doug in P.R.

Cooling System Additives - Turbo and High-Tech Performance Magazine

We find out how well cooling system additives really work and which is best - Turbo and High-Tech Performance Magazine

www.motortrend.com

 

[pippo]

You have a leak.

Could be, but if I do I cant locate it. Unfortunately, if I cant locate it I cant fix it.

 

[pippo]

Article says it works but not that much with a 50/50 typical mix of antifreeze/water. I think the best fix has to be get a bibber radiator. But, a bottle of that stuff is worth a try 1st! I hesitate to run just water with water wetter.

 

[melsg5]

Could be, but if I do I cant locate it. Unfortunately, if I cant locate it I cant fix it.

Have you tried a pressure tester?

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[92 Sunbird LE]

Forgot to add this, some of the early 2.0 head castings suffer from pourus aluminum, ( 2 different head foundries) I'll see if I can locate the article...

Doug in P.R.

 

[92 Sunbird LE]

Here you go....

Porosity issues​

In 1991, the Coscast cylinder head was replaced with the GM cylinder head which was manufactured by Kolben-Schmidt.[14][15] One of the most prominently recognized qualities of the Coscast head is its inherent lack of porosity; this was achieved by pumping the liquid metal into the mold rather than pouring it, hence, minimizing the presence of tiny air bubbles that usually form during the standard casting process. The Coscast head can be identified by a Coscast logo which is stamped under the 3rd exhaust port and a ridge on the head under the distributor.

The GM head was a poured casting, and featured a slightly different oil/water gallery design. These design changes required that a pair of Welch plugs be pressed in at either end of the head. In situations where a complete C20XE is still fitted to a vehicle, the presence of Welch plugs (or lack of) has proven to be the sole means of differentiating between GM and Coscast heads. A reinforced version of the GM head became available in the later years of the C20XE; however, these reinforcements meant that it had smaller inlet/exhaust channels than the other two.[16]

Since an engine's oil circulates at much higher pressures than its coolant, oil in a porous head has a tendency to gradually seep into the coolant galleries. A typical symptom of a porous head is usually a 'mayonnaise'-like substance forming somewhere inside the cooling system (usually, this can be found residing on the coolant reservoir cap). However, depending on the degree of porosity, symptoms of a porous head have a tendency to vary. Many C20XE operators have described the symptom as a curry-like residue or in more severe cases, a thick brown sludge which may overcome the entire cooling system. In such instances, engine oil will readily react with the sulfur in rubber components, hence quickly degrading coolant pipes and hoses to the point of failure. During the porous head debacle, GM faced bankruptcy – therefore dealers failed to recall affected models. Due in part, to the engine's immense prominence and demand, many businesses now specialize in the repair of porous GM C20XE/LET heads – by either sleeving the affected gallery or by injecting a polymer based substance into the porous region. Reportedly, a small number of total GM C20XE cylinder heads ever exhibited significant symptoms of porosity.

Doug in P.R.

 

[AustinandTrotsky]

You know about our cars- fan only comes on when it is in the RED zone- by that time, thew engine is destroyed, so I toggle switch my fan to ON way sooner. Coolant reservoir is wierd- I top it off, and it goes down to almost empty, retaining about only 1/2" of coolant. Then I top it off again, and same thing happens. But it never goes 100% dry/used up. But i am not burning coolant as I do not get white exhaust. Nothing is blocking the rad/condenser.

How do you toggle switch your fan to come on sooner?

 

[AustinandTrotsky]

Article says it works but not that much with a 50/50 typical mix of antifreeze/water. I think the best fix has to be get a bibber radiator. But, a bottle of that stuff is worth a try 1st! I hesitate to run just water with water wetter.

do you have a radiator that you reccomend?

______________________________

 

[92 Sunbird LE]

Red wire to fan( circuit breaker- fuse - battery.)

Black wire to fan ( switch - ground metal on dash)

Stock radiator works fine..

Doug in P.R.

 

[Apululu]

Sunbird LE, 2L, Coupé. 1994.
233.250 Kms
Hi, for the last 3 month's temperature was going up to red zone.. driving in mountain rich zone.. (Spain).. renewed termostate.. same thing.. also felt like I was loosing Hp.. Eventualy it was the catalysator.. full to the top...renewed him and flying again.