over heating

[elizar22]

i have a '97 venture that keeps on overheating.
i changed the t'stat,changed both fan motors,removed the radiator took it to get cleaned. they took it apart and cleaned it.
still kept on over heating .so i removed the t'stat.still overheating.
what can it be? help any1

[ademero]

The water pump impeller could be erroded away. Not circulating any coolant.

['97ventureowner]

At any time you opened the cooling system,(i.e. removing thermostat, or removing radiator,) did you ever bleed any air out of the system once you put it all back together? I've seen 'pockets' of air cause overheating problems which went away once they were removed.

[cjstew4]

Originally Posted by elizar22

i have a '97 venture that keeps on overheating.
i changed the t'stat,changed both fan motors,removed the radiator took it to get cleaned. they took it apart and cleaned it.
still kept on over heating .so i removed the t'stat.still overheating.
what can it be? help any1

First look at the posts on the first page of the Venture forum for intake gasket leaks and read most of them. Could be an internal intake gasket leak caused by a small external intake gasket leak or by that original bad tstat. Go to a place and have them do either a hydrocarbons in the coolant test, or a leak down test to determine if it is a head gasket leak. When overheated, is your overflow tank full? When cool enough where you can open the cap of the radiator, does the coolant want to just flow out and not circulate inside the radiator? My '97 broke down from overheating 300 miles from home at 1 a.m. Nursed it to the nearest big town. Next day, everyone believed it was the Tstat which was bad, replaced it at $300 due to the geniuses that designed its location, and still overheated. At a repair shop this week replacing the intake gaskets, going down to the head gaskets, etc. Whatever you do, do get it fixed before any out-of-town trips. And since it has overheated again since you replaced the tstat, my GM guy told me to replace the tstat again since it may have been compromised. Also, get rid of the orange coolant. Claims to be good for 6 yrs, isn't, and can contribute to premature gasket, etc wear. Refill with half green coolant and distilled. Keep us posted.

[cjstew4]

Originally Posted by elizar22

i have a '97 venture that keeps on overheating.
i changed the t'stat,changed both fan motors,removed the radiator took it to get cleaned. they took it apart and cleaned it.
still kept on over heating .so i removed the t'stat.still overheating.
what can it be? help any1

First look at the posts on the first page of the Venture forum for intake gasket leaks and read most of them. Could be an internal intake gasket leak caused by a small external intake gasket leak or by that original bad tstat. Go to a place and have them do either a hydrocarbons in the coolant test, or a leak down test to determine if it is a head gasket leak. When overheated, is your overflow tank full? When cool enough where you can open the cap of the radiator, does the coolant want to just flow out and not circulate inside the radiator? My '97 broke down from overheating 300 miles from home at 1 a.m. Nursed it to the nearest big town. Next day, everyone believed it was the Tstat which was bad, replaced it at $300 due to the geniuses that designed its location, and still overheated. At a repair shop this week replacing the intake gaskets, going down to the head gaskets, etc. Whatever you do, do get it fixed before any out-of-town trips. And since it has overheated again since you replaced the tstat, my GM guy told me to replace the tstat again since it may have been compromised. Also, get rid of the orange coolant. Claims to be good for 6 yrs, isn't, and can contribute to premature gasket, etc wear. Refill with half green coolant and distilled. Keep us posted.

['97ventureowner]

Originally Posted by cjstew4

Also, get rid of the orange coolant. Claims to be good for 6 yrs, isn't, and can contribute to premature gasket, etc wear. Refill with half green coolant and distilled. Keep us posted.

That isn't necessary, as it is now known that GM erred in claiming the coolant was good for 5 years/150,000 miles. You can continue to use the DexCool, just replace it every 2 to 3 years or 50,000 miles and flush the cooling system well before refilling with fresh coolant. It is also a good time to check or replace your radiator cap as these have been found to let air into the cooling system as they get older. I've made it a habit to replace my coolant in my '97 every 2 years/30,000 miles, and so far so good.