Exhaust Change fitment questions
 

Hey Folks,

I'm pulling out an OMC 454 (Donzi 22 classic) and replacing it with a 502 crate motor. I've pulled the OMC exhaust off (that was what caused the previous mill to seize up) At any rate,
I'm replacing it with manifolds and risers with new take offs from a 496 Merc.

Here's the situation/ question. The risers sit about about 4" higher at the peak than the old OMC stuff did. They angle down towards the transom and when rubber coupler hits the tailpipes they are about 2" higher than the previous exhaust. ...this is all been mocked up on the garage floor and I haven't installed the engine into the boat yet.

I am curious if I'll be able to force the rubber hose down a bit to match up with the tailpipe or if maybe I need to build a little angled coupler and spice that into the rubber exhaust hose to get the angle right?

Hope this is all clear. This stuff is new to me.

Thanks

Jay

Make an angled coupler. While the exhuast hose will bend, doing so can cause the water flow out of the risers to be restricted at the top of the riser (where the hose bends down. That can cause hot spots and melted hose. You might get away with it, but since you have the opportunity now...

A local welder should be able to fab something pretty reasonable.

it sounds like you are talking thru-transom exhaust. i think they make angled exh tips so the exhaust points down towards the water and up towards the riser. another option is make the elbows yourself out of fiberglass. i used PVC pipe once. they didn't last very long...

bending the hose will more than likely leak water, and as said above create hot spots and burn, cpperformance has an assortment of exhaust fittings so you can create the angles needed as well as have it looking good, if your mocking it up now do it right the first time and never worry again .......pvc?!?!?!?:lolhit:

hey, it was an attempt. there is only one way for sure to find out if something won't work.

not sure what 496 risers you have but there seems to be 2 different risers one about 10" and one about 8" be sure you have the shorter ones here is a pic of the taller ones