Muffler (for Sabb) & Exhaust Fittings

Hello All,

When I first got Calypso, I installed a water lift muffler on the exhaust of the 10 HP single cyclinder Sabb engine she has. However, a few months into cruising I had problems with the exhaust valve sticking open (no compression when trying to start). There were heavy carbon deposits jamming the valve in the guide. I assumed it was backpressure related. I removed the waterlift muffler and have not had any valve problems since. But my ears ringing!

In retrospect, I think the problem may have been overload related. I may have been running the engine with too much pitch on the prop (variable/reversable pitch).

Do other Sabb owners use a muffler? What type and what has been your experience.

I do have a new set of valves and guides. I have a compression leak - I presume it’s the valve/seat.

Second topic: transom exhaust fittings. Calypso originally had a 1.5" mushroom through hull for the exhaust. This seemed to do an optimal job of splattering the exhaust all over the transom. I replaced it with an ugly plastic fitting which had a built in rubber flapper valve. This has since turned to dust. So I’m looking for a good replacement fitting. I’d like to get something that protrudes a good inch or two from the hull - to limit how much splatter gets on the hull. The single cyclinder Sabb slugs the exhaust flow more than multi-cylinder engines, which seems to aggravate the splatter issue. I have not found any decent looking fittings from mainstreem sources. I have seen the drawings for the custom-fab SLM fitting. Does anyone have any recommendations?

I do have a 2" Vetus fitting with corresponding internal plastic goosneck (recovered from a wreck in Puerto Rico), but this size is overkill for my engine - I’d like to avoid mixing and matching exhaust hose/fitting sizes. 1.5" is what I need.


Jeremy, I have a Sabb 10hp with a Vetus waterlift muffler and have never experienced the valve problem you did. Could it be that you muffler was too low in relation to the engine and that caused excessive backpressure?

I don’t understand how you are running the exhaust system without a muffler either. You have water injection into the exhaust elbow, right? From there how does the water build up volume and then ‘spurt’ up and out the exhaust hose/pipe to the transom without backfeeding into the engine? Did you just remove the waterlift and leave the low run section of hose?

Also, don’t you have a high ‘loop’ in the exhaust just pryer to the water existing the hull to avoid backflushing when running downwind?

My only problem with the engine was running it with too much pitch(load) and rpm which caused it to run hot in the tropics, so I had to back off the pitch…which I guess took a lot of load off it but also would only maintain 5 to 5 1/2 knots.

This year I had to re-prop (electrolosis…my fault)and went down from the longer blades to the shorter ones. I’m still experimenting with this.

As for the exhaust splatter… yes, we get the too but it doesn’t botter us much. Couldn’t you have a short piece of bronze pipe brazed onto a bronze thru-hull?

The above link is the type of waterlift I have. And I can’t say for sure but I believe it is a 2" and I ran 2" hose. This thought has just caused me to eye-ball the exhaust hose and I think it is 2" ID. Maybe we have different exhaust elbows? My Sabb is a '78.

Jeremy, forget my last post. I didn’t read down the forum far enough to see the info earlier info from you and Rod.