| I just went through a
long process replacing my muffler and trying to figure out what was the
correct muffler for the engine .... as opposed to what was originally put
in when the boat was built!
The original stainless steel
muffler was, according to the Westerbeke manual and a few experts I
consulted, the wrong size. The mixing elbow in my boat was a 2" ID
elbow. The original muffler was then "necked" down to 1
7/8" on the inlet side and further "necked" down to
1.5" on the outlet. The outlet then goes via the 1.5" exhaust
hose to a 1.5" thru hull exhaust fitting.
Now....For what I discovered.
According to the technical manual for the engine, the exhaust should not
be any smaller then the size of the mixing elbow, which in my boat is
2". In fact, for every foot over 10' it should increase by one
half inch. Since my exhaust length was exactly 10 feet, this required that
I replace the old leaking SS muffler in my boat with a Vernalift 2"
side in - 2" top out muffler. I purchased this at WestMarine as a
normal stocked item for about $115. I then replaced all the exhaust hose
with the proper 2" size and replaced the exhaust thru hull with a
2" thru hull to match. According to the local experts I have
consulted (I could never actually talk to anyone "technical" at
Engines1 or Marine Diesel Direct) this will eliminate the unnecessary back
pressure the engine as always experienced and might even increase
HP.
After a lot of pain and
appreciation for my wife's small size and ability to fit into locations I
can only barely get my arm into ..... I now have a new exhaust system. |
