The overflow tank on my radiator also went away, with feeling. I looked for a replacement and had no luck. So I just mounted a one gallon plastic container that had used windshield cleaner. Attached to MH where old was located, used industrial size large wire ties to attach. Ran hose from radiator to this new overflow tank thru a hold that I cut into the screw-on cap. Two years ago and still running. Hope this helps.
1993 Gulfstream Sun Voyager DP 30'
200 HP Cummins B5.9, 4sp Allison AT542
Toad 1998 Honda CRV, 2006 Honda CRV
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