repairing an aluminum exhaust riser

[Gina Marie]

I found a rust spot under my starboard riser my mechanic indicated that if i sand it lightly then add an epoxy of some sort and keep monitoring it I can stretch out the life of the riser before I remove them. Any idea what I could use as a sealer????

Thanks

Gina Marie

 

[saltshaker]

Is it leaking? I would be careful here. I had a bad riser leak internally and coolant got into the #6 cylinder on a 6V92TA. Ended up doing a complete overhaul when all was said and done. If it looks bad on the outside then who knows what the condition is inside. I would replace it before you have a real problem.

 

[yachtsmanbill]

Aluminum doesnt rust. Is that a hose or a gasket or even a drain plug dripping? Are these Ns or Ts?? ws

 

[REBrueckner]

Sounds like it must be a water jacketed exhaust riser? If so, it's either stainless or cupronickel...copper colored. I have soft soldered the latter to stop a tiny water ooze, but for the former (stainless) epoxy is probably the way to go.

You could use liquid epoxy with a thickener to help build up some thickness over the hole or an epoxy repair kit available in hardware, marine, home supply and even pool supply stores. Fiberglass supply places would also likely have some. It's used for repairing swimming pool parts, metals, and bath tubs, for example, and seems to have strong adhesion.

I used to carry a small epoxy repair kit aboard my boats for such repairs....used it once on the housing of a raw water pump that was suddenly spraying water.....its an inexpensive repair item to carry aboard. Maybe someone else will post a current brand name they would recommend.

I found that the "temporary" repair on the outer riser shell lasted another 8 or 10 years I owned the boat but I always wondered if the inner shall was a heavier gauge metal. As noted above, you do not want to risk an internal water leak back down into aft cylinders....that spells major repair cost.