Bbosa

It's a 200tdi engine fitted in a formerly 2.5 defender 110 1983 model.

I have done some good work on the rad, actually it had some rusty parts at the bottom. i have also made sure the bleeding doesnt leave any air pockets especially around the stat. I also found the alternator belt worn out and replaced it. NOW the result is that the gauge settles slightly below the middle and it seems to be staying there even on hill climbing. Is this the normal position given that I have just rebuilt?

I will try a heat sensing thermo

no I did not replace it and it was working properly prior to rebuild. I may have to check on the airlocks though.

I will check on the above but how do I tell its the engine that is not hot or the vice versa?

I just finished rebuilding a 200tdi defender 110 engine. It runs fairly good but the temp gauge indicates its extremely hot on climbing hills and stays close to red till you switch off the engine. How do I tell its actually the engine that is hot or the problem lies elsewhere? I suspect it could be either the belt, temp gauge, rad. How do I rule out the head gasket since I just put a new one on rebuild?