I have a 1977 FJ40 that I had rebuilt here in Nicaragua, including a full rebuild and machining of the 2f motor last year. I have been running on longer trips at higher speeds the last few months and started to see a few instances when I would get high on the temp gauge. I moved forward with all new radiator, water pump and thermostat. But I fear it was too late and I caused a major major damage. The temp stays at a constant 87c, but does climb up when I shut off the engine (I replaced the electric temp gauge with a generic mechanical gauge). Everything seems fine, but if I start the engine without the radiator cap, coolant surges out of the radiator, and I have to constantly top off the reservoir. I also get a strange smell, possibly coolant when I let off the gas at cruising speed. The oil does not seem milky, so I don’t think it is getting into the oil. The radiator is also always under pressure, even when it is cold in the morning. I am going to go get compression test this week, but I am trying to prepare myself for the worst. Is it possible I just damaged the head gasket, or am I more likely cracked a piston, block or need to machine the block again? More importantly, are any of these symptoms safe to continue driving?
