Anybody familiar with the Slipstream folding prop?

[Loren Beach]

One more question please. Have any of your experienced the problem of the boat (preferably the 87 E34) pulling left or right under high speed forward power while using a two blade prop?

We have a flatter aft hull shape, being sort of a scaled up MORC design in general, but with the original stock two-blade fixed and the present two-blade featherer, we have no appreciable prop pull going forward. In reverse it wants to back to port, quite noticeable with the fixed prop and much less with the featherer. On our boat the shaft is on center, FWIW.

Best,
Loren

 

[34now]

wheel pull +3 blade, off-center shaft

Hey we had a lot of wheel pull (to port) on our 1988 E34. I put the details in a late March 09 post I started:
late 80's E-34- prop shaft position,
which you may be able to get thru at this address, or go back thru Maint and Mechanical by the title.

http://www.ericsonyachts.org/infoexchange/showthread.php?t=7266&highlight=Slipstream

Long story short the pull seems to be due to off center shaft and prop (do you guys have this?) as observed out of water sighting forward from center (prop is 3/4" to port) and/or teh assymetirc rudder (which would tend to make this type of wheel pull if enough assymetry. See the other post as I cannot remember all the numbers. We did not try to move the shaft nor did we buy a new rudder. Did a bunch of other stuff instead! including replaced teh sterring cable as the one side was worn out, and the quadrat was cracked.

We did put a new 3 blade prop on to replace th old undersized 2 blade. We put a Max prop feathering prop on there. Got a LOT more power and similar wheel pull at the same speeds, no less. So I am dubious about the idea of a 3 blade helping the pull. OUrs pulls enough to get very tiring and I put a thick bungy on it when motoring. When we take it out of gear most of teh pull goes away, so I think it is the prop wash.

I suggest seeing if teh prop is on center and maybe if we are lucky WE CAN FIND SOMEONE WHO KNOWS IF ERICSON/PACIFIC SEACRADT INTENDED FOR THE SHAFT TO GO OFF TO PORT. No answers to that one yet in this quest.
Enjoy the windy season!

 

[sailingdeacon]

34now: Yep, your situation is exactly like mine. I clearly see the shaft slightly turned to port - even thought the log (stuffing box) is at the center of the hull. For some reason I did not pay much attention to the pull earlier when I had a old feathering 3-blade prop... mainly because I did not rev it up because of vibration of the old prop. The new feathering slipstream high performance blade allowed me to rev up higher and notice the pull to port.

Yes, I get the same degree of pull to port as you - irritating - and yet none while under sail. It seems to me after many theories, we have nailed this down: while the 87 E34 (or later) is a suburb boat, this is its one flaw. I still love it.

I'll try the shock cord...