Weird cooling system issue
 

First, I have a 1988 turbo.

It has been overheating lately. The first time it did it I was out of town and towed it to a shop and they fixed a severly leaking hose. Picked it up drove it around, it worked fine. Drove it home (hour and a half down the highway) it was fine. Drive it the next day, it overheats again. Called the first shop they said get a diagnostic and get back to them.

I do so, and they say there are several leaking hoses. This shop is only like five miles from my house so I decide to try and get home and work on it myself. Pick it up, drive it and it works fine. Drive it the next day, fine.

Today I have time to look at it. And find that there is a leak somewhere in the system in the lower part of the engine, not worried about that yet, easy fix. But, once it starts getting up to temperature it starts spitting coolant out the valve near the thermostat. The thermostat is new, water pump is faily new. I can't think why it would do that. I am not the greatest mechanic so I need some ideas on this one.

idk if this has to do with it. but is the thermostat oem?

It was the last one in stock so if I had to guess I would say no.

well usually thermostats for rx7's that arent from mazda go bad.

wait.... valve by the thermostat? you mean the aux fan sensor or the weep hole in the water pump? have you checked your heater hoses?

AND ^ +1 get oem mazda thermostat, the aftermarket ones tend to get stuck resulting in a severely over heating motor or one that takes days to fully warm to operating temps.

I'm not sure what it is. It's in the same metal attatchment with the thermo. Here is a pic of it in action..

http://i38.photobucket.com/albums/e1...8/100_0088.jpg

Thats supposed to go to the overflow bottle. That is why youre overheating. When the car gets shut down it sucks air into the system.

Use only OEM thermostats, last engine i rebuilt was die to an aftermarket thermostat.

So, I should get a new thermostat. What are you saying about the overflow. I don't ever remember anything being attatched there..

Yep that's your problem right there. That "Valve" you were talking about, is supposed to be connected to a hose that goes straight to the plastic overflow bottle. That's probably the only "leaking hose" that you have... lol...

There should be a reservoir to the left of you hood latch, with a tube connected to the cap leading to that nipple.

heres a quick referance to what reservoir everyones referring too. you should have a hose running to this

http://i11.photobucket.com/albums/a1.../T2Engine2.jpg

While you're at it, never go to that mechanic again. If he doesn't know what an overflow is for, he's bound to mess your car up.

The only thing I can see going to that resivor is a hose coming from the radiator cap. Where would I attach another hose?