I can touch um without getting burned but its still hot. So my guess is they should be fine them 500 is pretty hot and with water running thru them should never reach 500 deg.
If you ever ran dry (blown impeller) it would not take long for it to reach that kind of temperature if you were running at cruise speed.
I run them on mine, no problems yet. I haven't lost an impeler with them yet either
You won't lose a impeller from using them an I'm sure they will work but for any reason you lose water flow through exhaust you will not be able to catch it befor it smokes the silcone when you are out cruising or wide open the std ones don't hold up to that either but the std ones can live longer under higher temps an when you do burn them. Now we sprung a leak captain lol
I don't think he's gonna lose the impeller....His is aluminum and 9" in diameter.....
I could be wrong but from what I have read these silicone couplers hold a higher temp then black Rubber exhaust hose.
You may be right i had burned a hole in my couplers be for an i was going to use the silcone ones from the simi shop but then talked to teage marine an they said dont run those just get the exhaust hose from imco so i did that an bought extra ones so i say F it run em see what happens they may last for ever i will say one thing the blue silcone looks alot cleaner
I still have my black rubber hose so if these silicon couplers burn or melt I can just replace it with a piece of my rubber hose.