the 75 engine is running on the hot side 110 Celsius I am running the engine in my garage with a fan pumping air to the radiator. Today I installed a new thermostat (195) Still running hot. Even with the fan clutch being bad, the amount of air i am pushing thru the radiator is equal to driving at about 40 mph. I am looking at pulling the radiator out and if I have to, send it out to get it recored. The funny thing about this is that prior to putting this engine in the 1984 jag, I ran the engine in the 1975 donor car and it did not overheat. Is there something I am missing? I don't want to strip down the engine only to find out later that it was something I missed. The water pump and thermostat are new. Is there air trapped in the system? Anyone knows how to bleed this system? Help????. By the way I am using the sending unit and gauge from the 75. Planning to use twin electrical fans when I resolve this issue. BYE, BYE to the clutch fan. FYI I also tested the temperature by using an aftermarket gauge connected where the sender goes. It reads 230F.
Thanks all

 

I would have the radiator re-cored. Having this done cured my Series 3 problems back in the early 90s.

There are no special bleeding techniques needed for these engines, (apart from having the heater valve open when filling). The design is essentially preWW2, although the DOHC head was fairly advanced in 1948 !

Is the engine just a swap, or have you rebuilt it ?

 

Just a swap. Did not overheat while in donor car

 

dumb question but did you also transfer the TEMP GAUGE from the donor car to the '84?

in other words, how do you know the donor car's TEMP GAUGE was not bad?

 

Contrale: HOT IS HOT. Pegged high with the donor car gauge, pegged high with the original 1984 gauge, pegged high with the aftermarket gauge. Getting ready to come and get my tapa de valvulas. See thread of how I resolved the issue.

 

Another dumb question... which car is the radiator out of?

 

the radiator was out of the 1975 donor car.

 

BINGO! that's the problema.