Prop

alaf1501

Junior Member
I own an 1989 E-34 and would like to get more power from my Universal 23hp. Does anyone have any ideas to share as far as using a larger prop?
 

Loren Beach

O34 - Portland, OR
Senior Moderator
Blogs Author
You need to provide us with more info. Exactly what type and diameter and pitch is your present prop? You have plenty of engine (probably a Universal M25XP). If you cannot maintain about 5.5 or 6.0 knots at about 2500 rpm against a moderate headsea, perhaps your present prop has too much or too little pitch. If you like lots of blade area, and do not mind losing a knot of sailing speed potential, change to a 3 bladed prop. If your prop is factory stock, it is most likely a two blade fixed.
As long as you maintain enough tip clearance (about 15% of the diameter of the prop) where the blade is closest to the hull, you want as much diameter as you can.
If you lucked out and have a feathering prop courtesy of the prior owner, just have the pitch changed.
You did not say if you are able to fully rev up your engine to 2900 or 3000 rpm with the present prop.
And if the present prop has too little pitch, it revs up to peak rpm's easily but the boat never goes over 5. or 5.5 in smooth water....
Loren
(1988 Olson 34 with a Universal M25XP and feathering Martec Prop)
 

sailingdeacon

Member III
Campbell prop

If you want power and sailing performance, and need to keep the costs down, seriously consider the Campbell 3 blade prop. See it at http://www.westbynorth.com/ If you email the guy, he will call you back. My experience two years ago was great. He helped me with the custome made prop and delivered it in two weeks. The company is small and the prop has some very unique properties. MIT studies are available. But best of all it is only a little more costly than a 3 blade MIchigan. For power with a boat your size and engine you have, you need a 3 blade prop. - especially against wind/tide/chop - as we have in this area of N.C. I had similar problems with a previous boat until I got the Campbell - and noticed almost no extra drag. I now have a E34 with a 30 hp engine and a 3 blade maxprop.
 

Anders

New Member
Anders

I repowered my E35 from an atomic 4 to a M25XPB and still have the 3/4 shaft with a Martec folding 12x7 prop. Is it possible to change the pitch on that prop to something that can be used, or should I get a new one with a larger diameter, and a more pitch? Anders.
 

Loren Beach

O34 - Portland, OR
Senior Moderator
Blogs Author
http://www.martec-props.com/

They are just down the freeway a bit... dime 'em up and find out if yours can be re-pitched.
If not, they often have trade-in props and might put together a swap deal for you.
IIRC, you may be speaking to a helpful person named Sheila when you call; if so, tell her I said hello.
Loren
 

Anders

New Member
Engine swap

I would like to know from e35 owners what kind of propeller they are using for the M25XPB and if they are happy with their choice? Anders
 
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