OldIHC

Just wondering if anyone has installed a valve on the heater supply to the cab heater so it can be closed in the summer months? I know it helps in releaseing some engine heat but the cab does get even hotter with the extra heat.

Most I've seen have a valve right at the cylinder head for shutting off flow to the heater. Not sure where you would find one, but 89799 R91 was the part number.

Pretty much like this one at ScoutParts, except the outlet was straight, and it didn't cost quite that much. Speaking of which, is someone going to grab the tailgate on Ebay for $2,500?

Thanks does that also act as a drain Port?

No. It goes on the top of the cylinder head, next to the valve cover, so would be at the top of the engine. The block drain is on the right (passenger) side, roughly between the back of the generator and the front of the exhaust pipe.

This is a picture of the valve I believe you are talking about. When I open coolant comes out but when closed I don't feel any difference inside the cab . Wonder if it is defective.

367972C92 is a 1/2"npt x 3/4" hose valve, I don't know what the part number is for 5/8" hose. The ones you have, the wings at the top open a bleeder, they don't shut off the flow to the heater. There are smaller valves for 3/8' NPT but again I don't have the number with me. All my trucks use the number I posted.
https://parts.kysorhvac.com/e2wShopping ... 3100002320
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