Rubber exhaust tube MI***

[Dually Driver]

When I put this basket case back together I didn't have a rubber flexible exhaust tube so I just went ahead. Now that it is up and running (slowly to break in the new gears and stuff)am I hurting anything running it without the tube that connects the exhaust to just in front of the prop???<br /><br />Mike

 

[hoot]

Re: Rubber exhaust tube MI***

i asked a similar question once. was informed that the hot exhaust escapes below the drive bellows and could shorten life of the bellows. maybe while moving not such a problem. maybe the hot exhaust could also affect the transom plate and heat up the bearing grease. probably not the best thing to do.

 

[jee70611]

Re: Rubber exhaust tube MI***

If you run it long, you could end up burning the exhaust valves. Without enough backpressure, the flames from inside the cylinder could escape before they burn out. I have run small engines for very short times without proper backpressure, but wouldn't recommend it. <br /><br />James

 

[Waterbugtoo]

Re: Rubber exhaust tube MI***

The only thing it will do is make more noise. It wont damage valves. Geeeze! Does thru hull exhaust burn valves?????? NOT!<br /><br />

 

[geriksen]

Re: Rubber exhaust tube MI***

Yea, this won't hurt anything. The Bravo III has an open ended bellows that isn't even attatched on the outside end. YOu can leave it off. You will just get some bubbling and a little more noise.

 

[jee70611]

Re: Rubber exhaust tube MI***

Waterbug,<br /><br />Geeze, You sure are defense eh? If I'm wrong just let me know OK. I will cede the issue to you . I was just giving my opinion based on what I have heard throughout my short life(nineteen).

 

[Ron-P]

Re: Rubber exhaust tube MI***

Waterbugtoo has a point, I had my bellows pop off the rear end on my Alpha1 and was concerned, but I was told that no harm to the engine will occur. My bellow popped off 50 miles from my home port cruising at 26mph happy to say no damage that I know of occurred.

 

[jee70611]

Re: Rubber exhaust tube MI***

That is good to know, because I was concerned with starting my motor with it out of the boat after I rebuild it. I figured I would just get a car exhaust and shorten it, but I guess an exhaust manifold off a car with a short pipe will do. That's what this board is for, to learn. Anyone else?<br /><br />James

 

[Bondo]

Re: Rubber exhaust tube MI***

the New model exhaust for the alpha is like the New bravo... only attaches to the transom end.....<br />run it... Louder is the Only draw back.....

 

[Waterbugtoo]

Re: Rubber exhaust tube MI***

jee70611,<br /><br />Didnt mean it to sound so offensive. Sorry bout that.

 

[Lou C]

Re: Rubber exhaust tube MI***

Dually, are you tallking about the exhaust bellows that is under the one for the u-joints? On mine, I noticed that the exh bellows is slit along the bottom, not compeletely closed like it shows in the shop manual. I asked around and found out that the aftermarket ones are like this (slit open) to let the exhaust exit faster to reduce carbon build up. So the only function of it appears to keep the ex from going up by the u-joint bellows. Mine would not ex at all from the ex holes in the bottom of the lower unit, most came out from the bellows and gimbal mount. I asked around and was told that this is ok. So maybe you want to put the bellows on for next season just to be on the safe side. BTW, real nice job on your boat, I saw the photos, did you rebuild the Cobra yourself??

 

[jee70611]

Re: Rubber exhaust tube MI***

Waterbug,<br /><br />I gladly accept your apology.<br /><br />Thanks,<br /><br />James

 

[Dually Driver]

Re: Rubber exhaust tube MI***

Lou C<br /> Yeah I put it all together. The guy that owned it drained the gear drive and didn't fill it correctly. He ran it with the uppper gears dry and you can see what happened. The gears were thumping so bad he thought the engine was broke so he took it apart. After he discovered it was the gears he was so disgusted he just wanted to sell. I bought it all apart and bought a new upper gear drive and put it all back together. I have about three gentle hours on it and it seems to be working fine, nothing leaking in or out..<br /><br />Mike

 

[Lou C]

Re: Rubber exhaust tube MI***

How hard of a job was it?? Looks pretty complex in the OMC shop manual that I have. I think the error while refilling is a common one, acc to OMC you have to take out the screw on the top of the outdrive, put it back in so it is resting on the threads but don't screw it in, then fill from the middle hole (slowly to let air bubbles rise to the top). Also if you get 2 quarts in you know you filled it enough. I let it sit overnight so any bubbles may get to the top, open top (level check) plug again, check it, then run it for a minute, stop, and check again.<br />If mine gets trashed and I am not sick of spending money (LOL) I may replace the OMC with a Volvo SX Cobra, these will mate with the OMC transom mount and you have to add an engine mounted impeller like the Volvos use. Nice smooth shifting cone clutch, and it is still in production, so parts are out there.

 

[Dually Driver]

Re: Rubber exhaust tube MI***

It wasn't too hard a job. I'm comfortable putting engines together, but never messed with a stern drive. I bought a Clymer manual from Amazon.com and it showed how to remove/replace components. Now, rebuilding some of this stuff is beyond my expertise and available tools. I'm well aware of my limitations and not afraid to get a pro when I need one.<br /><br />Mike