Having problem with muffler on 1978 Cape Dory sailboat. Welded once and now broken. Part not commercially available so we are considering having new muffler machined/welded. This is apparently a common problem. Any suggestions? Thanks.
Ljketchum@aol.com
Muffler problem with '78 Cape Dory Sailboat
Moderator: Jim Walsh
-
John
Fiberglass Muffler
Yeah, we also had a significant problem on our 30 footer. The pipe
leading from the manifold flange and the muffler were all
made of stainless. The problem is at the welds. It seems the welds
aren't passivated which allows the weld to fail from corrosion. We tried welding the seams and it helped for awhile until a new pinhole
leak would start somewhere else. As a result we decided to scrap the
entire stainless exhaust and made up a new riser out of bronze and
installed a Naqualift # ST-200 fiberglass muffler. The riser section was made from properly sized pipe fittings and all joints sealed with
JB Weld epoxy. The muffler was mounted on a marine plywood base coated
with West epoxy and the base glassed to the hull along side the transmission ( make sure you allow enough clearance for the engine movement fore and aft and side to side ). Everything except the plywood was available from West Marine. Don't forget to match the existing riser as closely as possible. The Naqualift is made by Marine Muffler Corporation. You will need to adapt the current hoses. We used a fiberglass elbow at the entrance of the muffler connected with a short piece of hose and from the other end of the elbow we used helical exhaust hose to make the fairly tight turn of the hose to meet the bronze 2" pipe nipple from the end of the riser. We came off the
exit of the muffler with the pre-existing exhaust hose leading to the
stern of the boat. Good luck.
leading from the manifold flange and the muffler were all
made of stainless. The problem is at the welds. It seems the welds
aren't passivated which allows the weld to fail from corrosion. We tried welding the seams and it helped for awhile until a new pinhole
leak would start somewhere else. As a result we decided to scrap the
entire stainless exhaust and made up a new riser out of bronze and
installed a Naqualift # ST-200 fiberglass muffler. The riser section was made from properly sized pipe fittings and all joints sealed with
JB Weld epoxy. The muffler was mounted on a marine plywood base coated
with West epoxy and the base glassed to the hull along side the transmission ( make sure you allow enough clearance for the engine movement fore and aft and side to side ). Everything except the plywood was available from West Marine. Don't forget to match the existing riser as closely as possible. The Naqualift is made by Marine Muffler Corporation. You will need to adapt the current hoses. We used a fiberglass elbow at the entrance of the muffler connected with a short piece of hose and from the other end of the elbow we used helical exhaust hose to make the fairly tight turn of the hose to meet the bronze 2" pipe nipple from the end of the riser. We came off the
exit of the muffler with the pre-existing exhaust hose leading to the
stern of the boat. Good luck.