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Lumbergh
08-25-2011, 10:17 AM
I am sure this is simple, but how does the exhaust keep water out while sitting on the water not running?

The rubber exhaust caps don't form a tight seal, so are there one way flappers upstream in the exhaust that hold water out?

Otherwise the exhaust would sit filled with water all the time while in the water not running.

Just wondering that while look at boat sitting in slip.

Thanks.

shepherd
08-25-2011, 10:45 AM
Not right now, Lumbergh, I'm kinda busy. In fact, look, I'm gonna have to ask you to just go ahead and come back another time. I got a meeting with the Bobs in a couple of minutes.


Ok.

Gravity keeps the water out of the engine. Look at the engine and you'll see the exhaust risers go way above the waterline. The flappers help keep the water from flushing in and up the risers when you back the boat down the ramp into the water or go into reverse.

Got it? I'm going back to work on my TPS reports now...

ricford
08-25-2011, 11:17 AM
Not right now, Lumbergh, I'm kinda busy. In fact, look, I'm gonna have to ask you to just go ahead and come back another time. I got a meeting with the Bobs in a couple of minutes.


Ok.

Gravity keeps the water out of the engine. Look at the engine and you'll see the exhaust risers go way above the waterline. The flappers help keep the water from flushing in and up the risers when you back the boat down the ramp into the water or go into reverse.

Got it? I'm going back to work on my TPS reports now...

See, it was simple.

Lumbergh
08-25-2011, 11:27 AM
Does the 1991 PS have mufflers between the exhaust hose and the transom flanges? Do these sit full of water then?

Just trying to understand the system.

Sorry if these are silly Qs.

tommcat
08-25-2011, 11:31 AM
has anybody seen my red stapler?

mayo93prostar
08-25-2011, 11:32 AM
Lum, yes there are mufflers under the floor. However, they are made of fiberglass, not metal. When you raise your motor box and look towards the back of the boat by the transmission, you should be able to see the "elbow" of the muffler sticking up and the exhaust hose attaches to this. there will be water in the mufflers when sitting in a slip, but as Shep said, it will not get into the engine.

shepherd
08-25-2011, 11:40 AM
Not silly. I just like that movie, sorry. :o

I think the flappers will keep the majority of the water out of the mufflers but I guess some may sit in the mufllers when the engine isn't running and the boat is in the water. But once you run the engine, the exhaust will expel most of the water out. Someone correct me if I'm wrong.

nitro5238
08-25-2011, 05:40 PM
The flappers mainly keep huge amounts of water from rushing in from the back should you ever find yourself in that situation.

Cooter
08-25-2011, 06:31 PM
MMMK? Great!

mikeg205
08-25-2011, 06:59 PM
Yup... everyone is right!!! if the water were to rise - above the risers you'd have a lot more to worry about than the engine... it's kind of like a siphon without the siphon... you would need a bunch of pressure to get the water over the risers..the flaps keeps the quick rush of water out... on a quiet lake you can hear the water gurgle in a bit...

thatsmrmastercraft
08-25-2011, 09:05 PM
Not silly. I just like that movie, sorry. :o

I think the flappers will keep the majority of the water out of the mufflers but I guess some may sit in the mufllers when the engine isn't running and the boat is in the water. But once you run the engine, the exhaust will expel most of the water out. Someone correct me if I'm wrong.

Right on the money. That's why when you start it after it sits for a few minutes you can throw some water out when it first fires up.