I just used this Bars Leaks stuff in my generator. It had a leak from one of the tubes in the core that corroded through. Put it in per the directions and the leak is sealed. I'm waiting on a new radiator to replace this one but I just wanted to keep the generator ready to run and also wanted to see if this actually worked,
https://www.amazon.com/dp/B002696FA2...t_details&th=1
FYI: The instructions say to use a different product for a "blown" head gasket. Not sure that really applies to your situation but just beware.
__________________
70 TA, 467 cid IAII, Edelbrock D-port heads, 9.94:1, Butler HR 236/242 @ .050, 520/540 lift, 112 LSA, Q-jet, TKX (2.87 1st/.81 OD), 3.31 rear
https://youtube.com/shorts/gG15nb4FWeo?feature=share