Exhaust routing / fuel tank

[Laker]

I am preparing to re-install my A-4 in my Columbia 34. The exhaust components are all out of the boat , save for the thru hull. The original install has the combined exhaust hose - 1 1/2" by Invincible of New Jersey (anyone know of that manufacturer?) - routed straight aft from the standpipe. My point in this post is that the reinforced rubber exhaust lies on top of the fuel tank. Locals I have inquired with have told me not to worry about that , given the exhaust temps , and the pre-buy surveyor did not raise a red flag , but I thought I would throw it up to this panel. Access under the cockpit is extremely limited. I have considered adding some form of insulation to the hose in order to give me piece of mind , a buffer between the warm/hot hose and the tank. I could easily add that material , then feed the hose back through the route. Getting in there to suspend or attach the hose to some other structure is practically impossible.

What say ye all ? Laker

[ndutton]

My only concern is where the hose touches the tank for reasons of chafe rather than temperature. I'd add a sleeve of larger hose around the exhaust anywhere there's the possibility of chafe.

[Dave Neptune]

Laker, I am not familiar with the below decks on you boat but here goes. Since it seems that the route over the fuel tank seems the most direct perhaps this may work. You install a stand/support on either side of the tank, then lay in a "trough" between them and lay the hose inside it.

Dave Neptune:cool:

[Laker]

Dave ,

The very limited access I have to the area through which the exhaust hose is routed , I do not have the option to construct a support such as you suggest.

Niel , The hose does not show signs of chafe , but I share your concern. That is why I am considering some form of insulation - to guard against chafe and lift the hose off of the tank. I haven't come to a conclusion as to what a practical material would be...

[gary gerber]

Hi, check out sandsinsulation.com they offer on their site foam insulation for a large range of pipe diameters. Their product line looks similar to the foam insulation one can find at home depot. If you don't have severe bends in the exhaust hose this might work for you.

[Laker]

Gary ,

I have no bends. I will check that out , and thank you.

[gary gerber]

I thought I would mention, having rebuilt my exhaust system, that when you go to attach the reinforced exhaust hose a tool I found extremely helpful is an
automotove tail pipe expander which will temporarily expand the hose to facilitate slipping it on fittings. A 1 1/8" to 1 3/4" I.D. expander retails for around $10.00.