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Posted By: samjaxfl 28 AB Radiator Cap - 06/28/22 09:41 PM
Hope everyone is doing well, happy Tuesday. Another question for anyone who may have insight if you don’t mind. Anything special about screwing these two back together?
I would have expected an overflow of some type which I did not see. The temperature gauge had a funny dry rotted seal between it and the cap which peeled away. Inside was a small brass screw and some other stuff that crumbled.
Figured I would put it back together with some rubber washers and stainless washers until it was snug but was looking for advise if that was not suggested.
Thanks Steve

Attached picture 28 rad cap 2.jpeg
Posted By: Rustoholic Re: 28 AB Radiator Cap - 06/29/22 03:33 AM
Hi Steve,

Welcome to the VCCA's website!

There should be an overflow tube coming out of the radiator neck that goes down to the side and dumps the overflow onto the ground. These wonderful old vehicles did not come with overflow tanks. As an aside, I added an overflow tank in each of my two trucks by attaching a rubber hose to the end of the overflow tube and ran that hose into a container. One one truck, the container is a whiskey bottle and on the other it is an old brass fire extinguisher. ;-)

When I put the '28 motometer onto my cap, I just cut out a washer out of 1/16 gasket material and have a brass nut under the cap to hold it on.

BTW, you can test the motometer by dipping the end into a cup of hot water. ;-)

Cheers, Dean
Posted By: samjaxfl Re: 28 AB Radiator Cap - 06/29/22 10:20 AM
Thank you
Posted By: TJPlatt Re: 28 AB Radiator Cap - 06/30/22 01:50 PM
Stupid question, does the motormeter probe have to be in the water/coolant to work properly? Reason I ask is my radiator will spit out water/coolant until it reaches it's natural level just above the radiator fins. When it's warmed up, there might be enough expansion to submerge the probe but I have not checked it out.

-Tyler
Posted By: Yobbo Re: 28 AB Radiator Cap - 07/01/22 02:16 AM
This article by the president of Motometer from back in the day answers the question of if the bulb should be submerged.
I found it on the internet so it has to be true.


Description: Motometer
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Posted By: Rustoholic Re: 28 AB Radiator Cap - 07/01/22 03:38 PM
Very interesting article. Thanks for posting it!

;-) Dean
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