What is this part called?

I need to replace the part of the exhaust system that sits bebind the engine in my '95 Sport Nautique. I have repaired it multiple times and believe that it is now beyond repair. This is the fiberglass cylindrical feature that I would think would be called the muffler. I can't find anywhere online that sells this part. Am I calling it the wrong thing? I can order it from Corrct Craft but it is quite expensive.

Any suggestions?

Check with skidim.com I know it has a specific name, but I can't think of it, it is effectively a muffler though. You could also ask on correctcraftfan.com of planetnautique.com for the part number and possible suppliers.

maybe bypass both mufflers with straight pipes and put in a fresh air exhaust...??? Just a thought.

It is the muffler. Pretty sure they're all made by a company called Silent Choice or Silent Rider. I take it you have blown a few impellers?

Silent Choice makes the exhaust tubes (mufflers) for DD's as well. I'd check there.

I go through an impeller every couple of years. Nothing unusual.

What I am experiencing is loss of power. When I increase the throttle the rpms increase as usual, but the boat does not accelerate as it should.

Heat is what kills mufflers is why I said that.

Michael said:
"What I am experiencing is loss of power. When I increase the throttle the rpms increase as usual, but the boat does not accelerate as it should"

If the RPMs increase but the boat speed does not then it is an indication that your tranmission is slipping. That wouldn't have anything to do with your exhaust.

Perhaps when you increase the throttle the exhaust simply gets louder and you are thinking the RPMs increased? Watch the tach next time and verify that the RPMs do increase.

Aside from that, it sounds like your muffler has been fried. As Trace said, it sounds like you ran without cooling water a few times.

Don't do that!

The first indication that your impeller has gone is that the exhaust will get louder. This is because the water flow through the exhaust is very important. When the flow of water stops the exhaust gets louder due to the gases not getting cooled and the baffling of the water is removed.

If you run for any distance without cooling water the exhaust system will overheat. On the engine the exhaust manifolds are cast iron which can take the heat. At the "riser" the exhaust and cooling water are mixed and everything downstream of that is rubber or fiberglass which can NOT take the heat.

I have seen boats sink because their impeller fried, lost cooling water and then the 4" rubber exhaust hose melted, opening a 4" hole in the back of the boat.

If you suddenly hear your exhaust get loud, STOP! Shut the engine down ASAP. The exhaust system can fry much faster than the engine will overheat.

And when you say you "go through an impeller every couple of years", does that mean you replace them on a preventative basis, or they fail that often?

If they fail that often then something is wrong. Are you running the engine while the boat is on the trailer? You don't want to do that either.

Rod

Rod,

Thank you for the info.

Yes, the tach indicates that the rpms increase as they should when the throttle is increased.

I understand that the loss of power is not consistent with a bad muffler. I was having the same loss of power issue last season. Patched up the muffler with some fiberglass repair and it fixed the problem.

The exhaust does get a little louder when a crack in the muffler develops, but not significantly louder.

I don't replace the impeller as a preventative measure. It burns up after about 3 seasons of running the boat hard (w/ around 1800lb ballast) about 2-3 times a week.

Is there anyway to test the performance of the transmission. I changed the fluid recently so it is clean and full.

I have never ran the engine dry. Anytime the engine starts getting hotter than 160 I shut it down.

"I don't replace the impeller as a preventative measure. It burns up after about 3 seasons of running the boat hard (w/ around 1800lb ballast) about 2-3 times a week."
This is the problem with your exhaust. Replace at beginning of each year. Has to be easier than replacing every three yrs, then reglassing the muffler.

The loss of power is whole 'nother can of worms...

Not replacing the impreller at the begining of each season is bad JU-JU..

wow replacing an impellar that much does not sound normal to me