CONTINUOUSWAVE

PHIL--I will follow your good advice

PHIL--your collected propeller data for my rig is especially good to know.

I am sure I will be able to [select] a new propeller [that will produce some unspecified benefit].

boat.jpg [Moderator's note: the original image has been cropped to eliminate the surrounding area and parts of the boat not related to the engine mounting heightand the propeller blade arrangement. Note that the forum is pleased to host and include in-line images into posts to the forum, and those ...

I will put [the boat under discussion, a 17 SSL] on a trailer [in several days or when the weather moderates]. Then measuring the location of cavitation plate, changing propellers, or changing [engine] mounting [height] will be easy. The boat lives in a slip on straps most of the time. With the data...

The CMC hydraulic bracket appears to give about 5-inches of setback and 5.5-inches of lift.

Thanks for your help. I will try out a larger pitch and then maybe ditch the jackplate. Those shallow flats on the coast are where I really appreciated that thing. Four or five inches really saved the day many times.

The current propeller is a PowerTech LNR three-bladed 14 x 18-pitch polished stainless steel. Further tests confirm less oscillation with three more passengers added to bow seats, but still oscillating occurs if much positive trim used. Ventilation also begins to occur with positive trim at higher s...

I completed engine break-in period [on a SUZUKI 90-HP engine of unspecified model designator] on 17 SSL boat. [The 17 SSL exhibits excessive up-and-down repeated oscillation of the bow] at all planing speeds, at any vertical height, and at any amount of positive trim. [Trimming the engine to] full-u...

Does the setback of the plate increase bow oscillation at any given height? Do propellers alter bow oscillation very much? [The propeller on the Suzuki DF90 on the 17 SSL appears to me to be] a very good three-bladed propeller with cup. I will review options [for changing weight distribution] and ch...

Thanks for replies. My [17 SSL] has a CMC hydraulic jack plate and the engine is mounted two-holes-up. This gives a 4-inch setback. The 17 SSL models have the battery, the fuel tank, and bench seat near the transom. They are tail heavy, unlike a Montauk. The propeller is a stainless steel three-blad...

[For any reader, who, based on their personal experience with Bennett SLT trim tabs on a 17 SSL with a DF90:] what are the benefits of the 6-inch-size tab instead of the 10-inch-size tab? BACKSTORY: I have re-powered [a 1989 17 SSL boat] with a [Suzuki] DF90. [The new engine does not have a] hydrofo...