Hi there.

Im michiel from the netherlands.

Ive got a new engine in my S4 RX7 But when i got it returned The garage said.
That my cool system wasn't working properly

So we replaced the Radiator, Cool Fan, and Under tray.
And everything was ok.

The meter about half way. So i was driving my new engine. Till The ADD COOLANT buzzer went of.
Pulled over and refilled the Cooland

After a while i had it again, so i checked. And a saw it leaking thru the expansion tank.
Went back to the garage, and he said it might be the radiator filler cap. That isn't working properly. So i replaced that one. BUT NOT WITH A RX7 CAP but A regular MAZDA CAP is there a differance ??

I does any body have a idea whats wrong.

I dont have whit smoke
I dont have sweet smells
The cooland is all going to the expansion tank and that is flooding...
So the system isnt leak.

ANYBODY !!!!

 

You want to replace the pressure cap, not the fill cap. The pressure cap has a spring and you should use only an OEM Mazda one (I'm not sure if different caps were used between mazda or not). The flat cap is just that, a flat cap with no spring. You may also want to change the thermostat if you dont know the last time it was changed with an OEM one only also.

 

If your coolant reservoir is overfilling it could very well be the radiator fill cap. After awhile the seal in the cap wears out and it no longer seals allowing the coolant to flow into the overflow reservoir. See what happens with the new cap. I would also ask your mechanic to make sure he bled the air out of the coolant system when it was first filled.

 

I have a pressure cap MAZDA OEM. with spring brand new.

I ve repleaced the coolant myselfe but i guess I've bleeded properly
Ive done it as said in the manual.

Thermostat i didn't replaced yet

 

With the car cold try cranking the car with the radiator cap off and see if a stream of bubbles comes out of neck or if it comes gushing out.

 

When i fill the system completly full, till the top of the fill neck.

And i crank the car there are bubbles and the water is gushing out.

 

if you get bubbles in the rad nozzle it means that compression or air reaching the coolant within the engine, therefore indicating that a coolant seal COULD be blown. i dont like to jump to conclusions. AND if there is a blown seal and you dont have alot of money its not the end of the world, theres a liquid weld trick you can use to temporarily fix it.

 

Hope it isn't my water seal.
Just got a rebuild. 2000 miles agoo

But there is no white smoke, only ad a cold start, when it warms up the smoke is gone.

My local garage, said i has to be air in the system.

 

How did you bleed the coolant system? What I normally do is run the car with the cap off for about 15 minutes with the heater on at full blast while gently squeezing the lower radiator hose until you see no more air bubbles.

 

I think i've bleeded wrong.

I had contact with the garage he said to bleed as following.

Run the car idle for about 2 minutes
Take the cap off.
Refill.
Cap back on

And do that until there is no need for refill.

But There must be air in there someware Just got to be

 

Wow, what a PITA...
I just keep the rad cap off and keep filling until it spills over.
Make sure the thermostat has popped open first - check rad hose temp with your hand.
Once it's topped off, put the cap back on.
This usually works.


-Ted

 

There should be an air bleed screw on the side of the radiator (at least if a factory or koyo one). I usually fill coolant, run car, then open bleed screw until all air comes out.

 

How do I make sure that the termostat is open ?
And following the manual of mazda i've te run the car IDLE when filling. Is that correct ?

 

The tstat is open when the car is at normal operating temperature. Yea just leave it running and top off, gently squeeze the rad hoses to help coax some stubborn bubbles out and to speed up the process.