454 330 horse with aftermarket Hardin exhaust. One side needed a new rubber exhaust sleeve due to a small burn hole directly behind the header. I replaced it and within an hour of run time it was back again. Water flow seems good and water wasn't very hot that was dripping from it. Header itself was warm but cool enough to touch. Any ideas?? I'm lost and want to get on the water badly!!

If the hose is bent from manifolds and tips lining up , the hose will burn through. It needs to be a straight shot or you will have problems. Most Formulas have silent thunder boxes and Formula puts their tips in a slightly different spot for the muffler box. Jeff Wurl

It does have a slight angle, but that wouldn't examine why the rest of them are working fine, and only one is burning out. Could it be a blockage of water going out?

you must not have enought water flowing during high rpm runs,,,i would backflush,or look for a restriction

Explain... Sorry for the typo

http://www.offshoreonly.com/forums/g...er-flow-2.html

another problem could be ,some of the old rubber pieces from the seapump impeller is blocking water flow,,,my guess is that you have enought water flow at idle ,,but not at high speeds,,,look for post about water seapump impeller replacement,,and backflushing ,,hope this helps

Agree!

I've had this problem years ago with a pair of Gil exhaust. Can you post a pic of the riser?

Turns out it (more than likely) gravel in the oil cooler.