(Home) Heating/cooling problem

Thanks for the info so far. I am beginning to think that we do have a suspect head/gasket, as the problem has got worse.
Running at standstill, with rad cap off (it's a Toyota cap), I get a lot of creamy froth and a lot of bigger bubbles. Revving the engine blows water out - seems to lose about a pint fairly quickly. It seems suspicious to me, but I don't know what it should look like with a 'good' one. Anyone able to describe?

The garage (Imperial Car Co, in Poole) said the coolant had been checked with some gadget which can identify the presence of combustion gases??? But I think we've had the rad done since then, so it's possible we have either multiple problems or just a new one.

Problems developed shortly after we had the vehicle, it has overheated several times. Did seem to improve for a while after new stat. No obvious wet patches under vehicle.
Get bubbling in the overflow tank after stopping, following a quite short run. The rear heater seems OK.
This afternoon I found that the front heater warms up (but only once we get going, despite the gauge indicating normal temp on the drive), Ok for a while, then blows cold for rest of trip. Stop for half an hour, drive off, and it does it again... Hmmm
The car otherwise starts and runs OK, and does not generally overheat on around-town use.

I have yet to check the fan.

TIA,

Malcolm

PS we have tried the recommended garage in Bournemouth (Waltham garage). It was they who replaced the stat, but they pointed out that they were not townie specialists. But still helpful and not over expensive. A little bemused at how they came to be recommended on the 'net as Townace specialist, though.

- (#7074) Malcolm Bebb, 7 Feb 03