Exhaust Flange
Morning John:If your beating yourself up trying to find a factory replacement for your exhaust riser, you can stop now. I've been through it with a Universal M25. The only part unique to the engine itself is the flange that bolts onto the manifold. Apparently every boat manufacturer that uses the Universal and other engines as well, custom make the exhaust risers/injectors to suit their particular model. Mine blew earlier this year and after calls to Torrenson and other supplier's, I finally figured that out. Like Rch said, the exhaust/riser/injector is simply 1.25 inch piping, elbows, and a nipple welded in the proper spot. Most are of black iron. You can take your exhaust out and take it to just about any plumbing/machine shop and have one made up to fit for a lot less than what you will pay a marina shop to do it. If your flange is in good shape, all you will need in addition is a gasket which Torrenson does have. If you haven't done it yet, I would soak the flange and associated bolts real good with WD40 or some other penetrating oil and let it sit for a couple of days before trying to take the bolts out.Luck!