Exhaust Insulation

DLSwan1961

unread,

Apr 19, 1997, 3:00:00 AM4/19/97

to

I am in the process of replacing the exhaust in my sailboat with a
water-lift type. In all the literature I have seen, it is suggested that
you insulate the short section of hot pipe between the ehaust manifold and
the water-injection point. Any suggestions on what to insulate it with?
Engine is an Atomic-4 30 hp gas.

Thanks in advance.

dls

Lionel Lavallee

unread,

Apr 20, 1997, 3:00:00 AM4/20/97

to

DLSwan1961 wrote:

Go to a speed shop and get some fiberglass cloth especially made for
the job. As a side note, they used to make the stuff out of asbestos...

CptnRn

unread,

Apr 21, 1997, 3:00:00 AM4/21/97

to

<<DLSwan1961 wrote:

This muffler wrap is expensive thru many marine mail order catalogues.
But I went to a marine chandlery next to a commerical boat basin that
specializes in supplying shrimp and other working boats and found 3" wide
muffler wrap at only 25% the cost of what is in the catalogues.

Daniel Branham

unread,

Apr 21, 1997, 3:00:00 AM4/21/97

to

test

JKline6766

unread,

Apr 22, 1997, 3:00:00 AM4/22/97

to

There is a reason that the water lift did not come with the atomic 4. It
will not start with back pressure on the system. That is why the boat mfg
that installed the atomic 4 went to the expense of water cooling the pipe
then dumping the water at the exhaust outlet. Many people have tried what
you are getting ready to do and ended up with water in their atomic 4.
Jim

Edward Seling

unread,

Apr 22, 1997, 3:00:00 AM4/22/97

to

I beg to differ. I ran an A4 with a water lift for several
years with no difficulties. Just has to be installed
correctly.
Ed Seling

Drew Lytle

unread,

Apr 22, 1997, 3:00:00 AM4/22/97

to

I did the water injection/pop exhaust upgrade to my atomic four about 4
years ago. First sail out, a following wave deposited water in the exhaust
outlet, which filled the pop exhaust, which, when heeling, backed up the
injection unit and flooded the engine. Major bummer.

However, after I dried it out, got it started and let it run for 4 hours to
evaporate any remaining water (I love Atomic 4's - they just keep going!),
I replaced the final hose from the pop back with a longer one that I
brought directly up from the pop exhaust inside the lazerette to the
highest possible point before sloping down to the stern outlet. I've never
had another problem.

I guess the two points would be:
1) keep the pop exhaust as close to the centerline and *below* the engine
exhaust outlet (and water injector) as you can
2) bring the exhaust hose as high above the waterline as you can *as it
leaves the pop exhaust* before sloping down the the outlet

Both of these will minimize the amount of water at any given time in the
pop exhaust, and prevent flood back to the engine from heeling or a rogue
following wave.

BTW, I kept the "hot" exhaust section as short as possible between the
engine and the water injector, and used fiberglass wrap about 2 layers
thick. It runs about 2 -3 inches from a wooden bulkhead and I've never had
fear of an ignition problem, although I liked someone else's comment that
you could put some metal flashing in between as a heat shield.

Drew.

JKline6766 <jklin...@aol.com> wrote in article
<19970422020...@ladder01.news.aol.com>...

Jim Demerest

unread,

Apr 28, 1997, 3:00:00 AM4/28/97

to

Edward Seling <e_se...@zharvard.edu> wrote in article
<335CDA...@zharvard.edu>...

>
> JKline6766 wrote:
> >
> > There is a reason that the water lift did not come with the atomic 4.
It

> > will not start with back pressure on the system. atomic 4.

> I beg to differ. I ran an A4 with a water lift for several
> years with no difficulties. Just has to be installed
> correctly.
> Ed Seling
>

I agreed with Ed. Ran a water lift with an Atomic 4 on my Ranger 29 for
thirteen years with no problems. The installation was recommended by
Universal as a fix to problems with the original stand pipe.

Jim D