Just for info value a long sustain climb up 500ft made Diesel Bongo hit 99C here so I just stopped for a bit !Simon Jones wrote:I read in one part of the thread that coolant came out the expansion tank but it was also mentioned no coolant was lost. One of these cannot be correct. Sounds to me like either the water pump is not doing its job, there is a blockage somewhere or there is an airlock in the system. Get an external temp sensor connected to one of the heads and you will be able to get a better idea of what is happening. On my V6 I think the hottest its got is about 96C on the climb to Applecross (Bealach na Ba), which if you know it, is basically like driving up the side of a mountain.
I am imagining that if your coolant is hitting boiling it is definitely going to be coming out from somewhere at that stage, overflow, seal round expansion tank, a tiny pipe hole. a pipe end seal. I think it might be worth trying to understand where the cooling inefficiency is that is letting it get that hot.
A thorough coolant system flush maybe, blocked channels in some parts of the engine, a fan not working that should or not running fast enough, rad as someone suggested, have you checked your oil level and/or changed it recently ? That is an important coolant which people forget (6 or so litres of it). Just a few thoughts.
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