If you trust Rock Auto….

Your upper hose is roughly 1.2” ID

Your lower is 1.5” ID

Alternate idea: buy one of the universal coolant flush kits. It will include a fitting that adapts a garden hose into your heater hose. Splice that into your looped heater hose to provide the inbound pressure. The t shaped fittings in this kit:

https://www.walmart.com/ip/Prestone-Automotive-Flush-N-Fill-Kit/16817507

Buy a couple cheap PVC pipe caps, the male threaded kind, and deadhead the radiator hoses into those. Maybe buy a few different male OD to make sure you can match your radiator hose IDs.

Clamp tight and you should be able to hold that 20-30lbs pressure Jerry referenced earlier.

Last edited by JW51; 07/13/2024 12:43 PM.
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