Hey, I just installed a new water pump on my 87 na and it did good cooling for about a day, but now the temp slowly rises past the supposed 1/4 of the way up the temp gauge. I am pretty sure it will over heat if I let it. What could it be? I am not running a thermastat and I dont have any other ideas of what it could be... How would I know if I had blown coolant seals? It doesn't have oil in the coolant but it is going somewhere. Any help would be nice. Thanks

 

Even with a perfect cooling system, you're going to run over 1/4 on a warm/hot day...If she goes much over 1/2, then start trying to find problems...If you're not blowing steam out of the exhaust, especially on start up, don't worry about the coolant seals just yet...

How's your overflow tank? Is it "adding" coolant after shutdowns? Is your rad cap in good shape? I've always run with a thermostat, though there are arguments for & against...Might want to try putting a known good one back in to see if that helps...

 

When does it overheat? All the time or only when ur stopped at a stop light? If it tends to get hot while ur idling it could be ur fan clutch. Just a thought.

 

it does good while it is running for about the first 10 minutes, then the temp gauge slowly crawls up tward going over half way. The over flow does get alot of water and steam after shutdown, and it doesn't burn coolant when you start it. I found a 13bt engine with and HKS turbo and a "tuned sport" transmission, whatever the hell that is, but the guy wants 1500 for the whole car, would that be an idea? What would it take to convert? Thanks for any help!

 

Sounds like you need a new rad cap first off...

 

so you think a radiatior cap could be the stem of the problems huh?

 

Also BTW it does the boiling coolant thing when you start it and run it warming up when it is cold. It doesn't make air bubbles, but it looks very agitated, of course, I dont have a thermastat in it either, could that do that?

 

If it were me, I'd put a new rad cap AND a new thermostat on her, and see what happens from there...

I am assuming through all of this that you've confirmed your fan is working...

 

Ah, sound like a bit of enlightenment here. Thanks will do that asap

 

Maybe air in the system?

 

Na, isn't air in the system and I am sure the fan is working, wouldn't make a difference going down the road even if it wasn't. Shiesh, this is getting to me. I wanna go kick something.... perhaps go to town and stomp some Honda stockie ***... hmmm..... thanks for the help

 

UPDATE:
Replaced the cap with a new one, both 13lb. Nothing different. I dont know what else could be wrong. I am going to get a thermastat asap but with out it it should run cool right? never warming up right? So WTF how come I cant keep this bastard cool?

 

Well, if you want to start dreaming about things it could be, think about a rad being clogged, a rotor housing passage or two all corroded up, the water pump housing corroded to hell, your temp sender being bad, yada, yada, yada...

Just thought I'd cheer you up a bit

 

Most likely as thermostat problem. I'd suggest a Mazda thermostat than a Stant POS.

 

I was having some cooling issues with my 88 convertible. I figured that the water pump may have been going bad so i replaced it. I also replaced the water pump manifold gasket. It is a must when replacing the water pump on any rotary engine. They eventually start leaking and could definitly cause an over heating problem. The gasket is pretty cheap. It runs about 4-8 bucks from dealer and to replace it, the purchase of a water pump gasket is required, 6-12 bucks from dealer as well. Replacing the manifold gaket is a pain in the *** though. It requires that you disconnect the oil nozzel lines which are at times brittle and easily damaged. I also replaced two coolant lines running from the upper intake manifold (which were badly corroded) and flushed the cooling system with prestone core cleaner (did it twice just incase). After completion...all heating issues ceased to exist.

 

See if you can rent one of those heat detector guns or whatever to see if you have any hot spots in your radiator. Do you have a clutch or E-fan?

 

I have a clutched fan, if I ran some of that cooling system cleaner through the 7 would it help? I heard it is extremely corrosive and would cause leaks on older cooling systems. Thank for any help, next step to cool it off is to drive it into a lake