my 89 spfi wagon has started gettin hot while driving, when I slow down it cools down, never over heats but it gets up there. I suspect if I ran the highway and didnt run the heater it would over heat.

 

I know my water pump is failing, it leaks occasionally from the weep hole. but it should still be circulating coolant

 

coolant is full.

no mixing of coolant and oil

no bubbles in rad while idling.

no steam from exhaust

 

 

could it just be the water pump failing

 

i doubt the rad clogged but i think i have a spare i can put in.

 

when i swapped the motor i flushed the whole system and it was all flowing freely. this was about 3mo ago

 

 

any ideas?

Edited January 15, 201511 yr by AKghandi

A bad water pump can cause it to overheat. Try and flush the radiator again. Any kind of blockage in the radiator could cause it to overheat under load but not at idle due to more heat when the engine is under a load, ie driving around.

thats kinda what I was thinking, but i dont know how the rad could have clogged, the cooling system has been cleaned and filled with fresh coolant.

 

with my other wag, half the rad was clogged and it would run down the highway just fine.

 

i will be replacing the water pump tomorrow hopefully that cures it

It probably is just the water pump. My mom's Taurus had the same problem, it weeped and would get hot when driving. Replaced it and it was fine. The other thing you can look for is a sticky thermostat. If it's only opening half way or partially that could be a problem too.

i was thinking i would do the thermostat also... its only a few more dollars.

When my gl was doing this it was due to a clogged radiator. If you have a spare one you know is good I'd just throw it in there to be safe as well as a new wp.

Fixed.

Water pump was a reman with the stamped steel impeller.

Replaced it with an import direct new unit with the cast impeller.

 

Also did thermostat and rad cap

 

Temp never goes above the 1/3 mark

Glad you got this resolved. Thank you for the update

you did all three things together so now don't know exactly what the cause was but, so many times it can just be a pooey old radiator cap - often the original just give up after 20 years or so.They are a service item and lucky for us the originals or genuine are of such good quality, most don't even think of replacing !

 

+1 for the update