YSB 8 Smoke & Carbon Issues - CD27

[Richard G.]

YSB 8 in my CD27 has lost about 1/3 power and is exhausting carbon and black smoke under any more than 1/3 + throttle. Increasing throttle position does not increase RPMs under load nor boat speed while under way. No problem at lower to medium RPM but definitely not full power. When advancing the throttle the carbon and smoke appear. In neutral, RPMs will increase beyond what they will under load.

Have installed a new exhaust elbow, new injector, recently had fuel tank cleaned and fuel filters for engine. Hull is clean, and do not believe although I will check, is there problem with prop.

Anyone with similar experiences and solutions?

Thanks.

[M. R. Bober]

It could be several things, but the most likely is a badly fouled prop. It's also the easiest to fix.

Mitchell Bober
Sunny Lancaster, (Where it won't be as sunny next week.) VA

[jneely]

I have had the same issues with the same engine on our CD 27. Cleaning the barnacles off the prop has always solved the problem. We had a barnacle "colony" the size if a softball at the end of one season. It is a wonder the prop could push the boat at all.

[Richard G.]

Thanks for the replies. Fouled prop was indeed the culprit. Glad to have replaced the mixing elbow and the injector as well as now no partially burnt fuel escaping and mixing elbow was original to boat as well.

Many thanks.

Richard