Also posted in the Alfa group and in maintenance, but thought I'd try here, too.
After a track session at an airfield day on Monday, I was shocked to find that my 75 had dumped a load of coolant on the floor under the car.
A quick check showed that the radiator fan switch had failed, so I topped up the coolant, bridged the switch connectors so it ran continuously on the ignition and largely ignored it for the rest of the day (although I did get into the habit of cutting the engine and letting the fan run for a while before killing the ignition from then onwards)
However, later in the day, I pulled into the Severn View services to grab a coffee and came back out to find it had done it again. When I parked up this time, I didn't give the car a couple of minutes to cool with the fan on.
The temp. gauge is reading normally - never climbed above 85-ish degrees. I know the guage is working, 'cos I've seen it climb as far as
110 degrees in traffic.The water is coming out under pressure from one of the hose connectors on the expansion tank.
Any ideas? - I suspect the expansion tank cap may be allowing pressure to build in the system rather than letting it bleed away. Is this a possibility?
Digging around, the head gasket is unlikely to be the problem, but it's not completely unknown, just incredibly rare. However, it's supposedly an easy job - only a couple of hours to do, so it isn't the end of the world if it is the HG.