Snuck home at lunch to check on my patch job ....
Nope, silicone not even remotely dry. Like toothpaste after 16 hours. I guess silicone does have a shelf life or the temperature encountered during storage can render it "broken." (Tube I used was stored in the garage
)
Am still going to try to salvage this sump. Just need to get some new silicone.
Edit - err hmmm. I have a new question but I should probably start a new thread for it.