Originally Posted by JW51
I just re-used the cap from the Harrison. Now I’m wondering what the replacement is rated for. How would I tell?

I'd suggest calling the supplier and asking what the pressure rating is. Be aware that if the radiator is built to handle a higher pressure, then the heater core becomes the limiting factor. It would need to be upgraded as well.

Any engine that routinely runs 20 degrees over the thermostat setting either doesn't have enough radiator, or the cooling system is terribly dirty.
Jerry

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