rsross314

Hey , been looking into the mazda rx-7s and reading up on the fourms for awhile about all the different problems. Well three days ago i found a 87 5 speed coup non turbo with lsd. great body shape new motor (around 40k miles) and the guy let me drive it and etc drove great the shifter needs a bushing set but i just ordered a short throw. anyway , get it home next day driving around add coolent light comes on , ok no prob must just be low. top the radiator off check the overflow tank and its full radiator was empty almost. now its needing coolent once a day at least but the overflow tank is fine , it overheated today on my way home and started pouring hot water and steam out of the overflow hose , but the tanks still full. new themostate put in the day i bought it. what would the reason be for it not pulling water in from the tank to cool it down? I saw the threads on the coolent seals but i havent had any experience with that and wondered if anyone can give me some help or advic. Thanks
By the way iv had plenty of experience in working on cars (piston motors though) in general my other car is a turbo awd eclipse yeah i know dsm . Thanks for any help on this. The fourms have already given me alot of help just by reading old questions.

311unity13B

the cooling systems work just like any other system, flush the system, check for blockages....are the hoses hard as a rock when hot? does the overflow tank fill up when u shut it off? check for leaks, look at all hoses, esp the one behind the upper intake and the ones below that, check for cracks in radiator, do a pressure test if possible

rsross314

No, the hoses arent hard when hot, and yes the overflow tank doesf ill up when I shut it off.l It would be much help if you could tell me how to do a pressure test. Thanks, any other advice is very helpful.

camman

Two things. Loosing coolant and rad not refilling from resevior. first if the rad cap is bad and not holding pressure you will loose coolant and possibly not refill. Second, if you have a leak you will loose coolant and there won't be vacuum to pull coolant from the overflow into the rad. It will just suck air from where the leak is. Find and fix the leak and install a new rad cap.

rsross314

Yeah i did check the radiator cap and it is pretty fubar , im about to ride up to town and grab a new one and then come back and check the hoses if that doesnt help. but also its smocking from the exhaust when i crank it now and theres some water/condensation dripping out i know thats not too unusual but just wondering if that has any connection maby? Thanks for the help guys.