Trojan Boat Forum

Has anyone ever used 17" props on an F32? Mine, as most, are 16", leaving only about 2" clearance to the hull, so there may not be enough cleaance for 17's, but I don't know how much clearance is necessary.

Thanks,
Dave

I believe my 4 blade props are 17x14.
They run well and I enjoy the extra control while docking.

Generally the clearance needs to be 1/6 to 1/7 the diameter of the blade. If you go from 3 to 4 bladed props, you can generally decrease the diameter by 6 to 8%. Or you can decrease your pitch. Ultimately, whatever your prop size, blade numbers or pitch, it needs to be set so your engine reaches top rpm. I was thinking about going to 4 blade, as I hear it is much more efficient at cruise.

I run 17*14 four blades as well with no issues...I like the way they have changed the handling of the boat. Much more reactive around the docks.

I am running 17 x 17 on my 1980 F32. Good perfermance and no handling issues when docking.

cclark75006 wrote:I am running 17 x 17 on my 1980 F32. Good perfermance and no handling issues when docking.

What engine and max rpm?
Those seem to be too much pitch.... RU overloading the engine?

Sounds more like 3 blades...

My F32 Has Merc 350 cid...17 x 17 3 blade At survey with clean bottom wot 4200 rmp 36mph on GPS

It's not still running that well now with dirty bottom.

I'm jealous...I am no where near that with 318's...4000 rpms but totally clean I only see about 25 knots wot. Time for more power!!!

Anyone have a cost figure for 17" 4 blade props, Can I expect to recoup costs in fuel economy.

17x20's here on F32 a/ 1:1 Velvet Drive & Cummins 6BTA diesels here ... 28mph

Away On Busine$$ wrote:Anyone have a cost figure for 17" 4 blade props, Can I expect to recoup costs in fuel economy.

No . you won't see any major noticeable change in economy assuming you what you have now are correctly sized and in good shape .

Cmount wrote:I'm jealous...I am no where near that with 318's...4000 rpms but totally clean I only see about 25 knots wot. Time for more power!!!

Remember 25 knots is almost 29 mph .

Away On Busine$$ wrote:Anyone have a cost figure for 17" 4 blade props, Can I expect to recoup costs in fuel economy.

I saw a little better speed but not much change in economy. I am going to have a slight cup added this winter. My cost was 1500 for the pair of brass blades. Tweaks are included in that.

Thanks Guys.