Hi, don't know a lot about my Hiace except what mechanic tells me, Super Custom 2.4 TD 1993. Last August he serviced it and topped up water in radiator...as i drove home and turned the engine off it was like a kettle was boiling in the engine area and water poured out from underneath. To cut a long story short mechanic ordered and fitted 2 new radiators and thermostat as he said there was a blockage and he said the 'boiling kettle' noise was the newly topped up coolant not having anywhere to go. Drove around with no problems until now...it's happening again but not quite as bad as last time. He's flushed it out and is at a loss as to what's causing it, it seems we can do short journey's but just been on a jaunt over the weekend about 70 miles and it's making the noise again, he's taken thermostat out by the way. Temp guage not unduly rising, seems to have lost some water out of radiator and sounds like a kettle boiling but it's not losing water underneath or from anywhere. He says it could be the head gasket or anything and doesn't seem to want to bother with it now. Anyone experienced this problem or have any ideas?