1/8 hydro engine/flexshaft installation

[Foolwitools]

Hi Guys,

I'm replacing the solid shaft in a 43" round nose. the motor mount is angled to match (more or less) the old solid shaft angle.

I'm thinking that the first thing I have to do is correct the motor angle. Do I want any angle at all (as compaired to the hull bottom) or is a slight angle better??

Does lowering the motor and mount as low as it can go have any advantage??

Bob the Fool :blink:

 

[Al Waters]

Bob,

I would keep the motor mount angle and as long as you can get a starting belt under the flywheel you are in good shape.

In going to a flex cable you will have an angle anyway.

Your next decision will be whether to use a 3/16 or 1/4 cable. I prefer 1/4.

To get a smooth curve transition from the motor collet to the strut, I simulate the distance and angle of the motor collet to the strut on a large piece of paper. I then take a driveline and lay it from the collet to the strut on the paper. This will give you the natural curve of the driveline.

Draw on the paper the outline of the driveline.

Then make a shaft log identical to the drawing of the shaft as it lay on the paper. This will also show you where to cut your hole in the hull where the shaft log will exit.

Good luck,

Al Waters

 

[Don Ferrette]

With the power of today's 67 motors a 3/16" cable in a heavy boat like a scale is a recipe for disaster. Go with a 1/4" with the stepdown stubshaft end to 3/16" like Aeromarine #1616.

 

[Mike Stewart]

Or 1/4" square drive flexshaft with 3/16" stubshaft. B)

 

[Foolwitools]

Thanks you guys,

more questions...........

Yes, I have a 1/4 cable w/stepped down stub in a teflon lined tube.

About motor angle, If I leave the existing angle in the motor mount the stuffing tube will end up with a hockey stick shape(only one bend)

I thought that an "s" shape ( two bends) was preffered................

Bob the Fool :blink:

 

[Hurricane]

There was quite a post about the bend and friction of a cable drive system so time ago and the S bend seemed to be the best, having the lowest amount of friction. Doesn't need to be much of a S bend, just a S. Not much differance with the lined or unlined tube as I remember.

 

[anthony_marquart]

Ive used both the s bend and the single bend. Don't know that I saw a big difference either way. If I have a boar with an angled engine I'll do a single bend,.. A horizontal engine gets an s bend. I've back to teflon liners only because I can leave the last 1/2 inch exposed. This makes strut adjustments VERY easy.

 

[Al Waters]

You need and S bend if there is no angle on your motor. If you have an angle on your motor and do not get an S bend, that is okay.

Look at it this way. If you want to know the most natural movement of a flex cable, hold the cable in between the palms of your hand. Rub your hands back and forth spinning the cable. Watch the end of the cable that is not in the palms of your hands. That is its most natural movement. A nice curve.

You are in good shape. Just select a shaft log just large enough so that it is not tight when you slide the driveline in to the motor collet but also not sloppy.

Good alignment is important also. You should be ale to drop the driveline in the shaft log and it fall right in to the moter collet (square or squeeze).

Thanks,

Al Waters

 

[Foolwitools]

Thanks everyone...............

I think I have a good idea of how this is supposed to go.

Happy Holidays,

Bob the fool :blink: