JP3 starter position

[Pluto]

Having had the starter off to replace the fan belt on Kennet's JP3, it is now not engaging easily - though it wasn't brilliant before. Both gears, starter and flywheel, are unworn, which may not help, but I suspect that it is the distance between flywheel and starter gears which is critical. Can anyone advise as to the correct position/distance?

[Laurence Hogg]

Having had the starter off to replace the fan belt on Kennet's JP3, it is now not engaging easily - though it wasn't brilliant before. Both gears, starter and flywheel, are unworn, which may not help, but I suspect that it is the distance between flywheel and starter gears which is critical. Can anyone advise as to the correct position/distance?

 

From the JP2/3 manual: THE CLEARANCE FROM THE END OF THE PINION ON THE STARTER MOTOR AND THE START OF THE GEAR RING ON THE FLYWHEEL SHOULD BE 1/16TH" TO 3/32ND"

IF THE STARTER BRACKET IS REMOVED NOTE SHOULD BE MADE OF THE NUMBER OF PAPER SHIMS UNDERNEATH THE BRACKET. THE THICKNESS OF THESE SHIMS CONTROLS THE BACKLASH WHEN THE PINION IS MESHED WITH THE GEAR RING, THIS SHOULD BE 0.015".

 

Hope that helps.

[Pluto]

From the JP2/3 manual: THE CLEARANCE FROM THE END OF THE PINION ON THE STARTER MOTOR AND THE START OF THE GEAR RING ON THE FLYWHEEL SHOULD BE 1/16TH" TO 3/32ND"

IF THE STARTER BRACKET IS REMOVED NOTE SHOULD BE MADE OF THE NUMBER OF PAPER SHIMS UNDERNEATH THE BRACKET. THE THICKNESS OF THESE SHIMS CONTROLS THE BACKLASH WHEN THE PINION IS MESHED WITH THE GEAR RING, THIS SHOULD BE 0.015".

 

Hope that helps.

Thanks Laurence, just what I wanted.

[Arnot]

Thanks Laurence, just what I wanted.

Just a note of caution, don't use aluminium shims like a friend of mine did, it creeps and thins out after a while.

 

The brass shim replacements seem to be doing the job though (but difficult for him to polish)

 

Regards

 

Arnot