I've been having a slight overheating problem after long hard driving. I've tried everything. 3 thermostats, finally got OEM, radiator clean+flush, fixed all leaks, new waterpump, and I've done the blown seal test( thankfully it's not) However, I have no air pump and have not upgraded to the dual pully yet and also need to get a better alternator belt because the one I have has stretched and I can't tighten it any further. It has about 1/2-3/4 inch play. Could this lack of power to the waterpump cause overheating due to poor coolant circulation?
Thanks,
Damon

 

its possible that the loose alt. belt is causing your problem, however there are many factors in the equation of overheating, osme of which you've covered already.

1. Thermostat
2. Radiator (not only flowing well but also the shape/cleanliness of the core)
3. Ducting/belly pan (or lack there of)
4. Clutch Fan
5. Oil Cooler (same principles as the rad)


Thats pretty much it....one thing to check for that I've noted as frequent cause of overheating is that if your car was equipped with A/C and has ever leaked at the condensor, the seepage of the refridgerant oils onto the front of the rad will quickly cause a large build up of crud and plug the flow of air through most of the core.

 

Did you check the connector(piece where you put the radiator cap) where you put the cap on both the radiator and the one by the intercooler on the passanger side, specifically The one by the passanger side is made of plastic and it sometimes cracks from heat which could be your problem.

 

I've got a wierd radiator cap set-up. I have no radiator cap. I only have the cap on the filler neck that has the nipple for the over-flow built into the flange. The cap I use for that is a pressure spring loaded one. I also bleed the system from the bleeder on the radiator whenever the engine is cold to burp it and also always idle the car at low RPM until heat blows out the vents before I drive it.
thanks,
Damon

 

its not a good idea to keep the clutch fan with only one belt, that is why they sell dual belt pullys when you get rid of your airpump. do you ever notice that belt slipping when your at a stop?

 

I just ordered a dual pully from bonzaitoyota. I'm also heading over to Kragen to get better belts. I don 't think I'm going to drive the car for more than around the block test drives until i install the new stuff. I haven't noticed any slipping, but considering the single belt is soo loose it has to have very little turning power. does anyone think that this could have the ability to affect overheating though?
Thanks,
Damon

 

just make sure to buy a pair of belts at once in the same package so you are sure they are the same length.

 

+1 for dual alt pullies.

 

No doubt, cool as crap. I can'y wait to see how it will affect my slight overheating problem. Hopefully it will fix it. Don't think I have a blown seal and this is the last thing it could be. I've checked everything on classic auto's check list, plus about seven more things.

 

ok, update, i just pulled the thermostat and i discovered everything is coated in this sticky brownish red goo. and the thermostat was really sticky so i think im going to replace it


what happens if i dont have one?

if i have 2 much water and not enough coolant can this goo (if you know what it is, its kind of oily) become, for lack of a better term, less gooy??

 

Make sure you order the thermostat from Mazda. Others suck. Check with your haynes manual for proper placement when installing. That goo thing sounds nasty. I have no idea what that is. Doesn't sound good though.

 

YOu need that radiator cap. Its what creates pressure in your system, without it your garunteed to overheat. Get a high pressure cap while your at it. For every pound of pressure the cap can handle you can add 3 degrees to your coolant boiling point so most people neglect this but its one of the most frequent causes for overheating.