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Tim Tim is offline
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First recorded activity by BoatBanter: Nov 2006
Posts: 19,107
Default exhaust hose...with or without wire

On Mar 23, 5:45*pm, bpuharic wrote:
On Tue, 23 Mar 2010 19:39:55 -0400, Wayne.B





wrote:
On Tue, 23 Mar 2010 19:15:38 -0400, bpuharic wrote:


looking to replace exhaust hose...one section has wire reinforcement,
another hose on other manifold does not.


any thoughts? this stuff isn't under much pressure and i think wire
can create local hotspots, leading to the wire tearing loose from the
hose over time....


engine is 350 merc on a 27' tollycraft


Hose is rarely attached directly to a manifold - it would get too hot
and quickly burn up. *Most often it is attached to something called a
"riser" or "elbow" which is the point where raw cooling water is
injected into the exhaust flow. *


yep, the old stuff is connected to the risers..



All of the exhaust hose that I'm familiar with is wire reinforced. *It
prevents the hose from collapsing when it is bent into a radius. *I
guess it's possible that if you had a totally straight run you could
get by without the reinforcement but I'd talk with an expert before
doing that.


these are pretty straight runs, but there's no guarantee, i think
that, as the hose ages, it couldn't buckle under use...- Hide quoted text -

- Show quoted text -


Well, consider the heater hoses n a car. Even in an enclosed system
like a car, there is usually a nylon webbing embedded inside the hose
and not steel mesh. Now on a radiator hose, especialy on the top hose
there is usualy a large "spring" fitting on the inside, to keep the
hose from collapsing and still make the hose pliable for shaping but
rigid enough to keep it from collapsing on cool down. then again we're
laking abotu nclosed systems on cars that run 190 degrees too.


Bob, if you're running a raw water system I think I'd just the simple
stuff with the nylon mesh inside. My hoses on my 350 GM are common
from NAPA. even the ones that carry the water to the manifold risers.
Now from the manifolds to the outdrive or exhaust ports in the hull,
that might be a different issue that I have no knowledge of.