...and so the saga continues. Had clients booked this morning and the wagon was running like a top. Weather was nice, air temps were cool and the wagon was doing it's thing. This afternoon had some running around to do and on an uphill run in an 80 k zone, the temperature gauge went catastrophic. I could see steam venting from the edge of the bonnet and I knew that was not a good sign. I pulled off the road and popped the bonnet. Radiator - intact. No signs of blown hoses, thermofans both operational. Radiator cap was sealed and pressure relief lever was locked down. Water pump appeared to be fine and belt was solid. Coolant reservoir was not good though. One side of the tank had failed, allowing steam and coolant to erupt from it. Still not enough to cause an overheat event. I have noticed the engine temp on the gauge has been slightly elevated recently but not enough to be a major concern. My money is on a bad thermostat. Managed to get a new thermostat on the return trip home, poured 2 x 2 litre bottles of demineralised water into it while overheating twice. Tomorrow is a national public holiday in Oz so I'm pulling the thermofans, radiator and thermostat housing and hopefully my synopsis of a bad thermostat is correct. If I can get it maintain coolant temps I'll have to do a JY run and find a decent replacement coolant overflow bottle. I may paint the radiator core with black epoxy paint to improve heat transference after giving it a clean inside and out. Grrr, it's only been back on the road 3 weeks since the drivetrain was patched up 🤬
*addendum - listing for the thermostat on the store parts listing was incorrect. I didn't find out until I pulled the thermostat housing off and was able to compare it with the replacement I'd picked up. Go figure...