So, I had an overheating issue last summer. Not really 'overheating', but running warmer than usual (varying from 1/4 to 1/2 on gauge when it used to be rock steady at about 1/3). Replaced thermostat, radiator, all hoses, and flushed block. No more 'varying'. Except that it would spit a little coolant into the reservoir tank and then not suck it back in. Replaced radiator cap. No more problem.
6 weeks later it has started the spitting-thing again. Every couple of days I have to bleed and fill the radiator and empty the coolant tank.
All replacement parts are from Mazdatrix.


Any ideas?

 

sounds like you have a blown water o-ring. rebuild or seal it

 

No evidence of combustion gases pressurizing the cooling system. Plus it seems erratic, it goes away for six weeks then comes back?

 

 

That sounds just like what my car is doing. Mine started when the radiator cracked. New radiator, cap, thermostat etc. Thought it I had it licked and the spitting into the overflow and not sucking it in is back. It is quite irritating.

Probably a coolant seal. If it's that I think my car is done. I've about had it with it. I am wondering if that's what cracked the radiator.

Be sure to let us know if you get it fixed.