Re: 51 300 Radiator Cap?

Posted by Don Shields On 2016/6/30 22:37:52

There is controversy surrounding the correct pressure cap for 24th through 54th series (1951-54) radiators due, I believe, to a typo in the 22nd-54th series parts list. Both a 7# and a 13# cap are listed for "all" 24th-54th series cars. That's quite a difference in pressure, could they be used interchangeably? I believe the 7# cap is for 22nd-23rd, the 13# for the 24th-54th.

At time of purchase, my '54 Convertible had a 7# cap with the correct filler neck length. It dribbled coolant out the overflow tube at the drop of a hat, even when the cooling system was nowhere near overheating. If you let that go long enough, the system will overheat due to a low coolant level. Installing a low temp. thermostat and an electric cooling fan made no difference in the dribbling. So I thought I'd try a 13# cap. Had a heard time finding one, finally Max Merritt located a 14# cap so I bought that. The new cap took care of the problem. No more excessive dribbling, no overheating and the coolant stays at the correct level in the radiator. Based on my experience, I recommend that Tim proceeds with the 13# cap and lets us know if that works for him.