Forum Discussion

aaron7's avatar
aaron7
Explorer
Oct 15, 2015

What pressure or temp radiator cap for a 440 powered rig?

Someone replaced our cap at some point with the red lever style and that broke off. Would like to replace the cap with the proper original one. Wondering what pressure/temp one would've been st...
Golden_HVAC's avatar
Golden_HVAC
Explorer
Oct 15, 2015
7 PSI and the red handle is a great feature. It allows removing the pressure so that the cap can be removed while 'warm', and also prevents the cap from turning while the red handle is down.

You do not want more than 8 PSI. Your older system is designed to run on 6-7 PSI.

Yes you will need a overflow reservoir, and you can find aftermarket ones at any auto parts store, rated to hold the 250F water coming out of the radiator while climbing a mountain grade.

Good luck,

Fred.

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