I have fitted the GM 10 Kw electric motor my cat so she now has 1 diesel and 1 electric motor . Fitting was not difficult and it all works ok . On launch though a problem revealed itself . The coupler could not hold onto the saildive splined shaft and so spun . No damage but now needs a better coupler. I need a splined sleeve with 20 splineds to fit inside the coupler by machining . This is very hard to find as the female spline is part of the flywheel so cannot be re used . As this is quite a popular conversion I hoped there was a coupler available to do this connection? Has anyone found such a thing ?
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coupler from VP 120S sail drive to 10 KW Golden Motor
- Thread starter gramos
- Start date
Option one: you take the original flywheel to a machine shop and they turn it down into a flanged spline hub. To this you attach whatever coupler fits your engine shaft via screws.
Option two: You buy Volvo Penta part nr. 22562311 wich is option one as made by the factory. It was used on 2001-2003 series engines before they switched to dampening. Hard to find used with good splines.
Option three: you measure the splined shaft, figure out what you need and order a splined hub online from a specialist supplier like splineshop then weld it into your coupler.
Option four: you take the input shaft housing off the gearbox (don't loose the shim) and bring it to a machine shop. They remove the shaft and machine the splines away turning it into a hexagon that fits a drive socket. The drive socket gets welded into your coupler.
Option two: You buy Volvo Penta part nr. 22562311 wich is option one as made by the factory. It was used on 2001-2003 series engines before they switched to dampening. Hard to find used with good splines.
Option three: you measure the splined shaft, figure out what you need and order a splined hub online from a specialist supplier like splineshop then weld it into your coupler.
Option four: you take the input shaft housing off the gearbox (don't loose the shim) and bring it to a machine shop. They remove the shaft and machine the splines away turning it into a hexagon that fits a drive socket. The drive socket gets welded into your coupler.
Thank you , I am looking at the option 3 as favourite.I think I have found a splined sleeve and already have a coupler which fits the GM shaft .
I am very curious as to wich norm the splines were made to, please share if you found out. I only know the outside diameter of the shaft but don't know the other key parameters like inner diameter, tooth spacing, tooth profile, etc.
This shafts were a known weakness for a time because VP didn't use any dampening between the engine and transmission, just a rigid flanged hub bolted to the flywheel. Option four was an aftermarket solution to the problem while VP switched to using a dampening element.
This shafts were a known weakness for a time because VP didn't use any dampening between the engine and transmission, just a rigid flanged hub bolted to the flywheel. Option four was an aftermarket solution to the problem while VP switched to using a dampening element.
HelmutSheina
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I was wondering if flexplate couplings are used on different installations, with this spline configuration? Otherwise look for something over the counter as mentioned by R above. If it is proprietary, I doubt a custom machined part would be justifiable. Love to hear of your solution, and it is an issue others will face.
The DIN is 5480 and the flywheel on the removed diesel had the spline mounted in a rubber coupling onto the flywheel .sizes of the 120S shaft is 21.60 mm O/D . 19.50 mm ID. approx 28mm length
HelmutSheina
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Oh yeah, and photos please? So many people are interested in similar setups, and pioneers such as yourself are writing the manual.
Attachments
Bottom up Coupler with spider, . 120S spline . 120S spline #2. Golden Motor shaft with key. GM side which needs a splined sleeve fitting inside , machining then weld new splined sleeve . VP flywheel spline on old engine.
Thanks. I see that N22x1x20x9H isn't exactly common this days, but it shouldn't be completely impossible to find.
Update today . After searching for a sollution in England for a few days I came back with nothing . So I made a guide from a 22 mm SS tube by cutting a slot 6 mm to take the key . Then I pushed this onto the VP splined shaft which gave me a guide for grinding a slot for the key . Very careful grinding using a battery drill gave a keyway into the splines . The shaft is hardened but it gradually gave way by 2.8 mm and allowed the coupler to fit using a 6 mm key.pictures to follow
Attachments
Another update , I,m not sure if anyone is really interested in this ?
After sliding the GM motor forward ,
I finished the keyway cut in the VP splined shaft and now have the coupler fitted using keys at each end .
So , big moment , I started the electric motor ( which has 2x 5kw Li batteries connected ) and the motor ran fwd and reverse .
The prop was rotating but at a very slow pace , same in both directions .
I tried the 3 speed settings on the EZ controller hand throttle , but whichever speed selected the prop was not turning at the speed of the el. motor , and little boat movement .
Something not right here ?
Having not stripped down a VP 120S sail drive I am now researching how they function .
Is there a clutch in the drive train ?
At the front of experimentation lay many hurdles !
After sliding the GM motor forward ,
I finished the keyway cut in the VP splined shaft and now have the coupler fitted using keys at each end .
So , big moment , I started the electric motor ( which has 2x 5kw Li batteries connected ) and the motor ran fwd and reverse .
The prop was rotating but at a very slow pace , same in both directions .
I tried the 3 speed settings on the EZ controller hand throttle , but whichever speed selected the prop was not turning at the speed of the el. motor , and little boat movement .
Something not right here ?
Having not stripped down a VP 120S sail drive I am now researching how they function .
Is there a clutch in the drive train ?
At the front of experimentation lay many hurdles !
Everything is working as it should, the gearbox provides a reduction, there are several ratios, 2.2:1, 2.48:1, etc. If you want to eliminate it the only way is to remove the gearbox and bolt the motor directly to the leg shaft.
UPDATE , I had a very useful suggestion from another forum and today implemented that and
It worked !!
Going back to the GM website I found the default direction was opposite to the direction of the VP 120s sail drive . A short interface online allowed the motor to be
set to match the sail drive and bingo ! everything started working , prop thrust / fwd/ rev , all as intended .
It worked !!
Going back to the GM website I found the default direction was opposite to the direction of the VP 120s sail drive . A short interface online allowed the motor to be
set to match the sail drive and bingo ! everything started working , prop thrust / fwd/ rev , all as intended .
Yupp, the mechanical Volvo transmissions (including I/O units) have cone clutches for fwd and reverse, and they are held in contact by a thread on the intermediate shaft. This means that they can only operate with clock-wise input shaft rotation.
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