No Direction

No Direction is our 70ft Narrowboat which is now home to my wife Jayne and myself, it was launched on 4th February 2008.

We spend the Winters in a Marina and cruise in the warmer weather.

Wednesday, 8 June 2011

Propellers and a Windlass.

Wednesday, 8th June 2011.
Moored at Stoke Bruerne.

Jayne has always struggled a bit winding the paddles on the wide locks here on the Grand Union Canal so today she ordered herself a LockMaster Ratcheting Windlass, they're expensive but as she doesn't want to steer the boat then we have to make things as easy as possible, so that's Jayne sorted, the other problem it more complicated and will no doubt cost more money.

And that other problem is our singing/noisy propeller, we have had the noise since the boat was new and expected it to wear off, the singing is the result of water leaving the trailing edge of the blades and causing them to act like a tuning fork, we get the noise between 1350rpm and 1650rpm but 1500rpm is our happy cruising speed so we end up going faster than we want to get away from the noise.  The "Experts" say reverse into a a shallow area so the gravel/mud will rough up the noisy edge but this didn't work and when the boat was in dry dock I got the angle grinder out and ground the trailing edge into a chisel blade shape, (another fix) this had already been done.

I had considered one of the square bladed Axiom propellers but after reading various blogs over the last year have decided against  it.

So after drawing a blank I contacted Crowther Marine who are acknowledged propeller experts and according to there reply with our 50 horsepower engine,  3:1 ratio gearbox and a 20x15 propeller our boat is under propped, that means it's like driving your car around in 3rd gear, I noticed last year when we were on the River Thames that we were a bit down on speed compared to similar boats, having said that I am happy with the Canal performance, Just want the noise gone.

 So where do we go from here? The gearbox ratio/prop size was the decision of Colecraft (the hull manufacturer and engine fitter)  and Beta Marine (the engine/gearbox supplier), the investigation continues and we will keep everyone posted.

The Offending Item

I get the impression that there a lot of boats owners out on the Canal who are not 100% happy with there Propellers.

1 comment:

Starcross said...

Ray,
I'm still having trouble with mine after a year. It has "good days and bad days" but is completely unpredictable. I'll be interested in how you get on.
Jim
Starcross