A better look for the waterbug

[Coyotes-R-Us]

Houston there Could be a problem... I just read that the type of clutch (Salisbury Clutch) off the old Johnson's where only rated to 40 hp. The 1600cc vw is rated at 60 hp. I'm thinking with the high altitude and loads of miles on the motor I'll probably be closer to 50 hp. Hope it will work...

[Corky]

I wonder...Do you think the clutch will have more or less load on it spinning a prop compared to moving the mass of the sled and riders ??? I'm thinking the load on the clutch will be significantly less with the prop...That should work in your favor also...

[Coyotes-R-Us]

That's what I'm hoping for.
I've looked at it hared and the exploded view and
Can't see where it can fail.
It is a splined steel shaft that it all slides on.
I can see maybe the belt slipping but that should/could
happen on any application . Same kind of belt on a 200hp
Snowmobile ???
https://www.manualslib.com/manual/95...page=77#manual

[Bart]

Looking at the exploded view of the clutch, I am not to familiar with this style. I hope this works, but you will be working 2 different governors, the clutch and the prop.
Where your clutch only has springs, which are rated for a 40 horse motor,
This would normally lead to some major over-revving, when matched with a 60 horse motor.
But with using the pitch of the prop, it should keep the motor from over-revving.
Now you can run into another thing to look at, with the clutch springs rated for a 40 hp motor, and using the pitch of the prop to keep your rpms in check. There may not be enough side pressure to keep the belt from slipping. Due to the torque needed to turn the prop.

[Bart]

when you say you can see the belt slipping, ,,, are you seeing the belt slip, or are you thinking it might?
CV clutches and slipping belts are not a good mix. slipping belts create heat, heated belts expand, & expanded belts will blow into a million pieces.
please put a guard or cover around the belt.
i have had a few belts explode on my snow machines in the past. when it happens it is a loud bang and will scare the heck out of you. usually i was racing across a lake or up a mountain side.
but there was one time i learn to respect the cover. i lifted the track off the ground, and was revving the motor to see how high the belt was riding up on the secondary clutch. for some reason i thought this is a dumb idea having the cover off. where i could look at the side and see just the same thing. so i put the cover back in place. revved it up one more time and the belt exploded, if that cover hadn't been there, i don't think i would have a face left, that's if i survived the impact. i wish i had a picture of what it did to the tub and cover of the sled. it would be a good show and tell. and the belt didn't even have a chance to get warm.
snowmachine belts have improved in the past 10 years. back in the 90's a belt would cost 70 dollars. and if it lasted 3 to 4 hundred miles that was great. (sometimes not even 30 miles.) this was on 100 hp sleds.
now the sleds are 180 hp. & the belts are 200 dollars and are lasting over 1000 miles. and a lot more is required of them.
technology has came a long way. and so has the clutching.
where you are working with an 60 hp motor. the clutching is still very important part, and little things cannot be overlooked.
industry had to come up with changes for the higher hp motors. but these changes can only improve the lower hp motors also. the first snowmachine i had, had only 60 hp. and the belts didn't last that long. due to heat build up.and on any given ride, i would carry at least 2 spare belts,
so something else to think about, on this build is how difficult will it be to change out the belt.

something also. is cv clutches / belts and water do not mix. my four wheelers have this belt set up also.and if water even a slight mist gets on the clutches. the belt slips.
so the cover needs to protect the clutches from rain, and water contact as you are out playing around.
i am not trying to discourage or distract you on this build, but as soon as the phrase belt slipping came up. so has a lot of memories from the past. from my school of hard knocks.
i would like to see this build of yours be an success, and problem free, from the get go. for you have put a lot of time and thought into so many small details on it.
hope the best of your endeavors
Bart

[Papee]

My thoughts are that on a sled take off locks it up. I think with the correct springs it would work the same as on a,sled in that instance. Where I think it will be a problem is letting off the throttle. I don't think there will be enough drag to keep the belt deep. You will have to over rev to get the clutch to lock up again. I think it would need constant pressure.

[Coyotes-R-Us]

I only hope to find out one day ....
A long ways to go yet

[Coyotes-R-Us]

A little more work.
I work nights and sleep most he morning, then Papa daycare
with my little Granddaughter, so I only get one peace a day fabbed up.
I still have to have my buddy weld it all together. But I have the secondary clutch on.
And working on the hub mount.
Looking about like I thought so far.

[Corky]

Well, slow progress is better than none...Are you running any bracing for the thrust to keep the tower from flexing ???

[Coyotes-R-Us]

YES I will, just don't have it on yet.
You think it will be a lot ?
I'm trying to make every thing mount to the "ring" that bolts to the motor .
So the motor can come off with every thing else staying in place.
And still move as the motor moves/adjusts...
I did how ever find out it will never clear the support beam of my boat port.
When I make the "cage" for the prop, it will have to Be hinged and the top will swing sideways
and I'll have to turn the prop to it's shortest spot.
Dang, about 10" to tall.

[Corky]

I'm trying to picture the stress on that tower as it enters/leaves the water or going over obstacles and slaming the front or back down...I would at least have a "tripod" type arrangement with a third support...Mabe even two coming down from the top on each side to counteract the thrust...You wouldn't need anything as heavy as the tower pieces just something to get the job done...
Remember how those first single plate type redrives flexed so much ?? And they weren't near as tall as what you've got there...Now the circle S redrive has evolved into a ladder type two piece unit so it can't flex under thrust... And the big V8 redrives are cast almost like a bellhousing so there's 0 flex with those too...Flex means stress...Stress means cracks...Cracks mean failure and flying parts..

[Coyotes-R-Us]

Thanks.
I'll keep that in mind, I tend to WAY over build.
I was planning At least supports one on each "Leg"
And one off the hub bearing/axle housing back to the Motor someplace.
I could run something to the hulls for an independent bearing surface, But it would have to Adjust
if I had to adjust the motor attitude.

[Corky]

Not only that you don't know just how much the hulls will move...I'd try to keep it contained to the "adjustable" area of the engine rigging as you've stated..

[Coyotes-R-Us]

Good point thanks

[Coyotes-R-Us]

I did a no load, no prop today.
All looked good. The clutch started to move at around 1800rpm.
I did not have my laser tack on the hub but it looked slower then the drive.
It starts out at 3x1.
As I increased the motor RPM the clutches both moved, as expected, the clutches
Topped out at 3000 RPM, right where I was hoping.
I should be like .70x1 there ,I would guess around the top end for the prop, 3100RPM.
I didn't run it long but It was quiet and smooth and looked to be running true.

[Bart]

now your cooking. have fun

[bgmcl60]

you keep going this thing is going to fly. not like an airplane i hope.

[Corky]

Great news !!!

[Coyotes-R-Us]

Well.
I did some more welding to make the prop tower absolutely ridge.
I did a dry running of the prop and drive at full power.
Every thing looked true and I felt no vibrations or odd sounds.
I did not run it long The clutch kicked in at 1500 rpm and at 3200 it
Had moved to it's extreme extent.
It is supposed to start at a 3 to 1 reduction then at full it should be at
near 1 to 1.
I was having a problem hand working the gas ,watching the motor tack, and
the lazar tack on the prop. But it looked like at 3200 motor speed it was 3100
prop speed. I was using my wooden 64" 34 prop.
It spun up to speed as fast at I could move the throttle.

I'm hoping the 3 blade 54" will load the motor a lot more, Or I'll need more prop.

I have since turned the prop around .
Sorry rookie mistake !!!!
Thanks Bart

[Coyotes-R-Us]

Ok !
I re plumbed the distributor as directed, and left off and plugged the second Vacuum line.
I used a * print out , worked great.
I found TDS on #1 marked it and took off the prop.
I fired it up with the timing light on it.
Ran it up to 3500 rpm and twisted the distributor till I hit
the stud that was used to hold the old manual fuel pump( I have it capped off ) and use an electric fuel pump.Not quite to the 28* mark with the vacuum line off as needed .
I was able to cut the stub off some to let the distb. turn farther.
I set it to 28* clamped it down, and put the vac line back on.
Put the prop back on and...
PERFICT!!! I now have enough HP to turn the prop up to the required 3100rpm.
That's all ,but it is right on 3900 rpm on the motor and holds . Nice.
I have a very short Video of the boat moving , on the snow.
Still lots of work to do like some way to steer , cage ext...
https://www.youtube.com/watch?v=aiE5J6tZvvI

http://https://www.youtube.com/watch?v=aiE5J6tZvvI