Mark 3 Starter

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Mark 3 Starter

Postby chasesa » Wed Jul 14, 2010 6:16 pm

Should the starter pinion turn counter clockwise when viewed looking at the pinion end of the starter?

My starter turns counter clockwise but when installed and engaged with the gear inside the primary it spins freely when starter button is pressed.

The driven gear turns freely in one direction but is hard to turn in the opposite direction which I assume is the correct direction to start the motor.

Suggestions?
Thanks
Stephen
1968 750 Commando
1975 850 Commando, Mk.lll
2004 BMW R1150RT
1966 Yamaha YDS3C "Big Bear Scrambler"
1966 Yamaha YM1 305
1971 BMW R75/5 (2011/12 winter project)
1975 Bultact Alpina 350 (when I get 'round to it)
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Re: Mark 3 Starter

Postby speirmoor » Wed Jul 14, 2010 6:46 pm

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Re: Mark 3 Starter

Postby lcrken » Wed Jul 14, 2010 8:40 pm

Starter should spin counterclockwise when viewed from primary case, the big idler gear it engages will then spin clockwise, driving the gear on the crankshaft counterclockwise, which is the direction the engine turns.

Sounds like you might have the sprag clutch reversed.

Ken
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Re: Mark 3 Starter

Postby L.A.B. » Thu Jul 15, 2010 3:36 am

lcrken wrote:Starter should spin counterclockwise when viewed from primary case, the big idler gear it engages will then spin clockwise


No.

The starter armature turns CLOCKWISE-when viewed from the primary side, as its gear engages with the small idler gear [5] and not the large overload backfire device gear [6]. http://www.oldbritts.com/image/1975_g12.jpg

Image

http://www.oldbritts.com/e_start_gears.html
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Re: Mark 3 Starter

Postby Ron L » Thu Jul 15, 2010 8:23 am

As LAB says, the starter turns clockwise. If yours is turning counterclockwise, has it been converted to a four pole field coil with four brushes? When using a Harley field coil and brushes, you need to move the brushes one position in the holders or it will turn backwards.
Ron L
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Re: Mark 3 Starter

Postby lcrken » Thu Jul 15, 2010 12:59 pm

Oops! My bad. Looks like I left out one of the gears in the train when working it out. Should have been more careful.

Ken
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Re: Mark 3 Starter

Postby chasesa » Thu Jul 15, 2010 2:17 pm

Thank you All. With your advice that the starter turned clockwise I was able to get the starter shop to make the fix quite easily. It's a 4 field conversion (with 4 brushes) but was turning counter clockwise. Thet fixed it easily, AND upon installation, voilà, it woked perfectly!
Regards!
Stephen
1968 750 Commando
1975 850 Commando, Mk.lll
2004 BMW R1150RT
1966 Yamaha YDS3C "Big Bear Scrambler"
1966 Yamaha YM1 305
1971 BMW R75/5 (2011/12 winter project)
1975 Bultact Alpina 350 (when I get 'round to it)
chasesa
 
Posts: 190
Joined: Wed Dec 26, 2007 5:25 am
Location: Fredericton, NB, Canada


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