If I drive my 88 TII around the block it overheats so I pulled the thermostat out to see it it was the problem and I noticed when I took the cap off thats on the neck that comes out of the motor I noticed that water wasnt circulating. Would that be the water pump? any help would be appreciated thanks!!

 

Check your coolant hoses for tears....The same thing was happening to mine and it turned out that their was a hole in one of the hoses. The smallest puncture could cause the pressure to go down far enough to cause the coolant to not circulate.

 

Hmm almost 100% sure hoses are all good. is there any way to test the waterpump out of the car??

 

I'm not sure on an FC. But on the back their is a tiny hole. If their is moisture or small droplets it is bad....

 

if no water is circulating, (and there is water to circulate in the first place) then it would have to be your thermostat. They are notorious for going bad, or opening spiratically, I'm thinking about just knocking the center out of mine because it acts goofy.



It is possible that the water pump has quit, but i don't think i've heard of one quitting before. Just take out the thermostat, and refill the coolant system with water to see if it's pumping. If it's not pumping without the thermostat it would have to be your pump.



If it is pumping it's the thermostat. Just remember that without the thermostat there is a good chance that the coolant will move to fast to act as a good heat absorber, so you'll have to replace it with a factory mazda thermostat.



also air can cause huge problem in the fc's coolant systems. Make sure it's been bled properly.

 

I tryed to get all the air out of the system, is there and specific way to bleed the system??

 

it is also possible for a waterpump to be bad and it not leak.

The impeller inside the pump could be rotting out so it

wouldnt circualte coolant right.



Try a new OEM thermostat first, its cheap to change and if you

never changed it since you had the car now is a good time to do it

along with a coolant flush.

I never had air in the coolant, if you fill it properly you dont really get any,

but with the car warmed up you crack open the bleeder screw for a second.

 

I usually let my car run with the thermostat housing neck-cap off for aboout 10 minutes. Air will regularly bublbe to the top. When the coolant level decreses to where you can't see it, just add water.



When the thermostat opens it will try to splash some out, if possible, have a buddy hold the car at about 2000 rpms so the coolant flow will be constant, not shoooting out the top.



before you take it for a test run, make sure to add coolant to the overflow resevoir. Air bubles will slowly bleed their way out through the tank, you just need water to replace it.

 

Air in the cooling system.





I always drill a 1/8" hole in my thermostat before I install it. This way no air can get caught at the top just behind the thermostat when its closed. Sometimes this will happen and the thermostat will malfunction because its air vapor instead of coolent up at the top next to the thermostat.





The water pump isn't too bad to replace if that is indeed it. Just plan on a Saturday to do it if its your first time.

 

I would replace the thermostat first and see what happens. I drove my 88 na around for almost 6 months with my normal operating temp being about half way up. I thought this was normal until I replaced it with a new one and now the temp sits under a quarter! All that time my thermostat was wrong as a matter a fact I think it was a non-oem one. You can check the water pump for play in the shaft to see if its going out.