Noob question here:

I'm starting to work on my XJ more & more. I replaced the t-stat couple weeks ago. It went just fine. I realize this is prob simple for most but it was big job for me. Anyway, I used red rtv to seal the felt gasket, it was only way I could get it to seal. I waited 24hrs to refill coolant so rtv could setup/cure. Well now my radiator has a slow leak. Could be coincidence, my 2001 xj does have 125k miles. I'm planning to replace the radiator this weekend. I plan to do the water pump at the same time. I'm concerned about getting the water pump sealed without rtv. Could the rtv have caused my radiator to spring a leak? Is this a no-no? Any suggestions?

Also, anything else I should consider doing while I'm working I there? I may replace the serpentine belt too, what about the fan clutch? It seems to work just fine now but if I'm there I was considering it too.

Couple years ago I put a Hayden tranny cooler on too. Noob mistake, I mounted it in front of electric fan. I'll prob relocate it in front of radiator fan.