Mercruiser165 exhaust dilema...

[Oshkosh1]

Re: Mercruiser165 exhaust dilema...

My new "plan of attack" here is as follows...assuming I don't find a good used elbow.

Plan "A" is to order a new one from OSCO...online for $120 or so. I'm also going to look at a riser from a 3.0L...which may(or may not) fit...in which case I'll simply attatch it with the bellows I already have. NOW...because I'm sure that whatever God it is that oversees such endeavours is not smiling on me at present, I don't plan on this working so...
"Plan B" is to have a 3" stainless pipe custom bent(I'll bribe them using bbq'd brisket...the currency of the stomach!lol!) to fit.

Ah, good grief...I might as well skip A and go right to..."B" 10lbs of tasty smoked meat and sauce to a mechanic is a no brainer!

 

[fishrdan]

Re: Mercruiser165 exhaust dilema...

Riser (top) - part that bolts to the manifold (looks like an elbow, does a 180 degree turn for your application)
Exhaust pipe (bottom) - bolts to the transom assembly
Exhaust elbow (middle) - goes between the riser and pipe (might not need one if rubber coupler/bellows will attach riser to pipe directly)

 

[achris]

Re: Mercruiser165 exhaust dilema...

Riser (top) - part that bolts to the manifold (looks like an elbow, does a 180 degree turn for your application)
Exhaust pipe (bottom) - bolts to the transom assembly
Exhaust elbow (middle) - goes between the riser and pipe (might not need one if rubber coupler/bellows will attach riser to pipe directly)

Correct name for that part is 'Exhaust Elbow'... Check any of the Merc manuals or parts diagrams....

 

[fishrdan]

Re: Mercruiser165 exhaust dilema...

Correct name for that part is 'Exhaust Elbow'... Check any of the Merc manuals or parts diagrams....

Hot dang, you're right! ( and I was wrong)...

So "Riser" is slang then, I guess?

Sorry for the confusion oshkosh

 

[Oshkosh1]

Re: Mercruiser165 exhaust dilema...

Sorry for the confusion oshkosh

I knew what you meant...

 

[Will Fish]

Re: Mercruiser165 exhaust dilema...

How about using a 3" rubber exhaust hose from the exhaust pipe, directly to the riser?

 

[Oshkosh1]

Re: Mercruiser165 exhaust dilema...

As it stands...there is no riser per se.

There is the original pipe, and the elbow. There's only about a 6" difference from the bottom of the elbow to the top of the pipe. The problem is that there is a severe bend needed. If I could find a rubber bellows long AND flexible enough to not crimp, THAT would be ideal. Can't find anything like it...so far the only thing that comes close to working is flexible stove pipe from an old pellet stove I have. It will take the heat, and is flexible enough to make the bends. 3" stainless is a no-go...not enough room to bend, and 2" galvanized is the only other option.

 

[Will Fish]

Re: Mercruiser165 exhaust dilema...

I was able to rig an exhaust using 3" exhaust hose (2ply reinforced w/ steel), with 2 fiberglass 3" 45s. I eliminated the upper exhaust pipe, coupled a fiberglass elbow to the lower exuast pipe, extended the fibeglass w/ 3" hose towards the riser, then another fiberglass 45 bending up, which I put a 3" exhaust hose onto and directly to the riser. I did not take pics of it, but will once I get back to the boat during the week.

Seems to work pretty well, as there are not 2 90's restricting the water flow.

 

[Oshkosh1]

Re: Mercruiser165 exhaust dilema...

I was able to rig an exhaust using 3" exhaust hose (2ply reinforced w/ steel), with 2 fiberglass 3" 45s. I eliminated the upper exhaust pipe, coupled a fiberglass elbow to the lower exuast pipe, extended the fibeglass w/ 3" hose towards the riser, then another fiberglass 45 bending up, which I put a 3" exhaust hose onto and directly to the riser. I did not take pics of it, but will once I get back to the boat during the week.

Seems to work pretty well, as there are not 2 90's restricting the water flow.

Sounds like what I'm thinking...
I tried get some pipe bent, however there is only about 4" of vertical space from the bottom of the elbow, to the top of the pipe. Couldn't make the bends.

So my options are:
1. Rig up a system similar to yours...using 2 45deg elbows and a small piece of straight pipe to join the two.
2. Use a piece of 3" chimney flex tube
3. Go through the hull...Probably not a good idea, I think that straight 6 would sound like an old tractor!
4. Keep the old piece meal 90deg...NOT what I want to do.

Where did you find your 45deg elbows??

A problem I have is that on MY elbow(for the 160, NOT the 165)...the pipe is only 2 1/8" not 3".

 

[Oshkosh1]

Re: Mercruiser165 exhaust dilema...

I found high temp silicone tubing(good for 400deg).

http://www.siliconeintakes.com/index.php?cPath=14&osCsid=6fd8c7bd509c4aa6fc6297e7ccfbd7af

Easily cut and joined. Best thing is that because of the difference in sizes I have (elbow exit is 2.5", exhaust pipe is 3") I can buy pre-manufactured bending reducers.

My only question is about the heat tolerance. Will this system see over 400deg heat? I don't remember the elbow being particularly hot to the touch though.

 

[Will Fish]

Re: Mercruiser165 exhaust dilema...

I found high temp silicone tubing(good for 400deg).

http://www.siliconeintakes.com/index.php?cPath=14&osCsid=6fd8c7bd509c4aa6fc6297e7ccfbd7af

Easily cut and joined. Best thing is that because of the difference in sizes I have (elbow exit is 2.5", exhaust pipe is 3") I can buy pre-manufactured bending reducers.

My only question is about the heat tolerance. Will this system see over 400deg heat? I don't remember the elbow being particularly hot to the touch though.

I am not familiar with the silicone hoses, but if the heat tolarance is acceptable, I would imagine it would be easier to install since it should be more flexible. I picked up the 2 45's at my local marine store, and are prefabricated fiberglass for exhausts.