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I have had to replace the top rad. hose last week & as a precaution I did the bottom one as well. All seemed ok for 3 days now the little hoses that go to to the TB split on the way home tonight so I replaced them - they were pretty soft after 12 years I suppose. I then filled up the rad. and ran the engine with the cap off for a few minutes to let the air locks out. Then a funny thing happened - I started getting like a foam coming out the filler neck - anybody seen this before?

Is thi sthe first sign that the head gasket is going & leaking,

thnx

I can't say I've seen that, but it takes quite a long time for the system to purge itself of air, so that may be what you were seeing.

The correct procedure is at page E2-6 - you purge with the cap on, then check the level, top up and repeat. Do that and you won't see the bubbles

If you have a head gasket leak, you will lose coolant over time, as the gases force the coolant out, so just monitor the level daily before starting the engine.

thanks Ian - but I still don't understand why all the hoses split over such a short time!

Was it just a small leaking split or was it a violent burst of coolant? My guess is that the water thermostat is stuck closed or some object (like a gasket or o-ring) dislodged from somewhere and jammed into it. I've seen that before on my old mx3. The o-ring for the thermostat somehow ended up all chewed up and stuck in the thermostat. What type of hoses did you purchase? The ones from Mazda or just the OEM ones from a parts store. I find the Mazda ones are quite a bit stronger than the basic rad hose.

I hope that helps...

wouldnt be too bad to drain system and flush it. When you fill it up, fill it up, then let it warm up with open cap, then let it cool and then fill up again when its cold and you should be set

well I finally found out what the problem really was - the stupid thermostat was jammed shut - the rubber seal in the middle around the spring had persihed & wrapped itself around the spring!