Grease crankshaft in primary

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Hey guys,

I am rebuilding my primary.It may sounds stupid, but would you put grease on the crankshaft or leave it dry when rebuilding the alternator on it.
I had the conversation with my stepbrother who’s a mechanic.
Regards
 
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not sure i'm understanding you're question. are you saying to lightly grease the crankshaft when installing the alternator rotor? if so, I don't think a light coating of grease would hurt anything.
 
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not sure i'm understanding you're question. are you saying to lightly grease the crankshaft when installing the alternator rotor? if so, I don't think a light coating of grease would hurt anything.
yes that’s what I’m asking. Grease it or let it « dry », cleaned off course
 
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yes that’s what I’m asking. Grease it or let it « dry », cleaned off course
just installed an alton e-starter, and when installing the alternator rotor, installed it dry. again, I don't think a very, very, light coating of grease will hurt anything. in my case, the rotor assembly was a very snug fit, so if I would have used grease, most of it would have been displaced by the rotor.
 

texasSlick

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The key prevents rotation of the rotor, the light coat of grease can be expected to ease removal of the rotor when necessary. One can extend that logic to the engine sprocket, but In the case of the sprocket, I opt to have the additional friction of the taper to prevent rotation, so would NOT apply grease to the sprocket taper.

Slick
 

Fast Eddie

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Indeed, I would NOT grease any taper fitting, they working by binding, grease works to prevent binding, so wouldn’t seem right to me.
 
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olympus

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Hey guys,

I am rebuilding my primary.It may sounds stupid, but would you put grease on the crankshaft or leave it dry when rebuilding the alternator on it.
I had the conversation with my stepbrother who’s a mechanic.
Regards
Put grease on the crank and leave it to dry?....No, and anyway it will never dry
Just for clarification are you suggesting putting this onto the crank gear taper or the chain teeth on the sprocket....the answer BTW is still No
The whole point of the tapers is friction... applying any sort of lubrication could cause it to spin
Assemble everything clean & dry
 
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I fully understand the taper and friction thing, and i'm assuming, you mean the crankshaft chain sprocket install, however, the sprocket is keyed - same with the alternator rotor - it's keyed. not trying to argue the point, but the original question was referring to the (keyed) rotor install. somewhat of a noob, and trying to jog my memory, but the way i'm looking at it, the chain sprocket needs to fully seated in position and it's keyed to prevent rotation. once installed, you shim the clutch sprocket so the two are in alignment. the taper is there, IN MY OPINION, so the sprocket can only install one way, and to be fully seated, as a starting point for sprocket alignment purposes, and has less to do with a friction fit to prevent rotation. while I did install mine assembly dry, I still say a very light coating grease shouldn't hurt anything. again, not trying to argue the point - just my 2-cents FWIW. peace....
 
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concours

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The key prevents rotation of the rotor, the light coat of grease can be expected to ease removal of the rotor when necessary. One can extend that logic to the engine sprocket, but In the case of the sprocket, I opt to have the additional friction of the taper to prevent rotation, so would NOT apply grease to the sprocket taper.

Slick
+1

rotor is a slip fit, keyed and then clamped, it’s not out in the elements, so no corrosion. No lube is needed.

Do NOT grease the sprocket taper.
 

oldbeezer

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I agree with Fast Eddie as to the taper fitting & friction, similar to the aau taper fitting to the end of the cam shaft to which there is no key.
 
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