Don't be tempted to replace your muffler with just any design. Catalina's design is simple, but it is no accident. A muffler must have the correct geometry and volume to minimize the possibility of water flowing back into the engine when the boat heels. A customer's report illustrates the point:

During a re-power by a very well respected yard, it was suggested the muffler be replaced with an "upgraded" production built muffler. After all of the money spent for the new engine, the customer felt it was a smart idea.

Motoring out the first day, the new engine performed beautifully. But after a fine sail, the engine refused to start. Back at the yard, water was discovered in the engine! After much time, confusion, work, and expense (for the yard), the engine was rebuilt and they were back sailing... with the same result!.

After two engine rebuilds, they finally realized the problem was with the muffler design. Water from the muffler was flowing into the engine through an open exhaust valve when the boat heeled under sail.

• Base: 13-1/2" X 14-1/4"
• Top: 11-1/2" X 12"
• For additional dimensions, refer to the annotated photo at left.

If you decide to replace your old muffler you will need to confirm the dimensions above and the dimensions on the photo below under "More images" match the muffler in your boat. We have no way to guarantee this is the muffler installed in your boat as Catalina didn't maintain records as to which muffler design was installed in each hull. If the dimensions match, it is the correct muffler. If the dimensions don't match, order our Aqua Lift Muffler, Custom part #Z2877 pictured below.

1) This item does not conform to the shipping table in the Shopping Cart. Additional shipping must be calculated. When you place your order we always call with a shipping quote before billing your card. For a quote in advance, just call 800/959-7245.

2) A 50% nonrefundable deposit will be billed when your order for this special order item is accepted. The balance will be billed when the product ships.

3) This is a custom made part. You provide the information we need to build this product for you. Once you order it we are going to build it just for you, just as you asked. We never want to see it again, and no one else wants it either. So be careful and order it correctly the first time because it can't be canceled, returned, or magically changed into something different!

Two ways I have seen an old muffler fail are:
A) The seam at the bottom edge can fail. This can sometimes be repaired by removing the muffler. After a thorough cleaning, you may be able to saturate the failed joint with WEST epoxy, clamp and allow to cure.

CAUTION! The muffler must be pressure tested to 5 PSI while immersed in a water bath to check for leaks after any repair is attempted. Carbon monoxide is colorless, odorless, tasteless, AND DEADLY. If it leaks after your repair, YOU COULD KILL SOMEONE. We highly recommend the installation of a carbon monoxide detector.

B) The bond between the inlet tube and the box itself can fail. This typically occurs because the vibration of the engine is transmitted directly through a rigid hose to the stationary muffler. In this case, it is impossible to achieve a successful repair. Even with the installation of a new hump hose to help isolate the vibration (which we highly recommend), there will be much vibration transmitted to the fiberglass tube. To be strong enough, the repair would have to be made on the inside of the muffler where you have no access. In order to leave the enough fiberglass tube exposed for the hump hose, a repair from the outside would be too small to be secure enough given the serious safety concerns involved.