Re: [electricboats] Elco vs ePropulsion

Update: I'm excited.  I just placed an order for new brushes for my original ETEK motor.  Found that Thunderstruck has them again.  We'll see if they fit.

 

From: electricboats@groups.io [mailto:electricboats@groups.io] On Behalf Of Myles Twete
Sent: Monday, October 31, 2022 11:46 AM
To: electricboats@groups.io
Subject: Re: [electricboats] Elco vs ePropulsion

 

I can't imagine that the drive efficiency loss thru the "90 degree turn from drive shaft to prop" amounts to much.  The big loss is in using a small prop.

My outboard conversion has served me well now since converting a 25HP 2-stroke Tohatsu to electric in 2003.  There are few with conversions or kits running today that predate this.  Thunderstruck Motors had started not long before this and had not yet offered its boat kits yet---I bought my ETEK from them after watching them drag race motorcycles in Oregon in 2003.  My telling them about my boat and buying the ETEK from them may have got them interested in targeting the boat market.

Initially, I was not super impressed with the performance of my conversion, yet I was sold.  But then initially I was running with the stock 9.9" prop.  It did not take long before I modified my lower unit to accommodate up to a 14" prop.  I have been running with a 12" diameter 3-blade brass prop for about 18years now and have been quite pleased with the economy.  The amount of efficiency gain possible in going to 14" might be worth the expense and hassle, but probably only a small percentage.  Still, I may consider that one day.

One thing I will never do: Eliminate the lower unit gearing for some other drive or relocation of the motor to an underwater pod.

I do need to replace my original ETEK 8HP motor very soon.  It's served me well for 19 years+ now, but with 3 sets of brushes nearly gone now and none available anywhere these days, I need to upgrade.  I'm considering brush and brushless options.

-Myles Twete, Portland, Or.

The Reach of Tide: www.evalbum.com/492

 

From: electricboats@groups.io [mailto:electricboats@groups.io] On Behalf Of F. Neil
Sent: Monday, October 31, 2022 11:16 AM
To: electricboats@groups.io
Subject: [electricboats] Elco vs ePropulsion

 

I would recommend checking out the ePropulsion outboards. I first bought an Elco 9.9 and was not happy with the noise and low efficiency. I then bought an ePropulsion Navy 6.0, which is much quieter, and much more efficient with its' larger 3 bladed props. The Elco is basically built on the bottom unit of a small-propped gas outboard, and loses efficiency in the 90 degree turn from the drive shaft to the prop, whereas the ePropulsion is a more modern design, with direct drive motor underwater that the prop is directly attached to. There are lower kW units that would be cheaper than the 6.0 that would be appropriate for your smaller (displacement?) boat.