Pinion Shaft ...Whoa !!

[Five Five]

While re-assembling my 107" motor I ran into a little issue that put the brakes on the project .... so I thought I would post my findings and results in the event any of you should run across this.

Here is my question to S&S cycle (tech support)

Subject: FW: Pinion shaft re-assembly

Hello Dean
I have a tech question regarding my S&S motor .... I am re-assembling my lower end and while putting the gears and keyways on my pinion shaft I noticed a lot of linear movement of the oil pump drive gear along the pinion shaft around .100"... It just doesn't seem right. Attached is a short video of the gear .... spacer ...gear ...am I missing something.

Bill

[ame="http://www.youtube.com/watch?v=LJgN_7fqv88"]http://www.youtube.com/watch?v=LJgN_7fqv88[/ame]


Here is the response from S&S ...

That is exactly how that should work! Generally there will be around .100" of play.

Dean

 

[barhopper]

Nice. You da man.

 

[Five Five]

Nice. You da man.

It took me about 12 hours to re-assemble the motor and fire it up ..... "It sounds so good" ..... :2thumbs:

 

[RazzBarlow]

Congrats, Bill! I know you've been itching to hear that sound for a while!

 

[Five Five]

Congrats, Bill! I know you've been itching to hear that sound for a while!

Thanks Razz .... cant wait to get off work and put some miles on her ...

:2thumbs:
"Five"

 

[john sachs]

55,
While the play/movement is normal, you need to be sure the oil pump drive gear on the pinion shaft has the chamfer facing the inside of the motor. :up:
John

 

[Five Five]

55,
While the play/movement is normal, you need to be sure the oil pump drive gear on the pinion shaft has the chamfer facing the inside of the motor. :up:
John

John ..... in the video the chamfer is facing outside I did pull the gears and spacer off to put in the woodruff keys.. gear, spacer, gear, nut .... I cant say with 100% certainty the orientation is correct ...... I will pull the cam cover and take a look .... I've put a few miles on the motor ...what kind of damage will it do if the chamfer is facing the outside ??

 

[pisssed]

It took me about 12 hours to re-assemble the motor and fire it up ..... "It sounds so good" ..... :2thumbs:

Glad You back on the road 55!:up:

 

[john sachs]

55,
There is a radius machined on the pinion shaft where the drive gear butts up against.If the gear is installed wrong it can set up a stress riser,which will lead to a crack around that part of the pinion shaft......(chamfer needs to face radius).:2thumbs:
John

 

[Brew]

Congrats on getting her running Five...:2thumbs::2thumbs:

 

[Five Five]

Glad You back on the road 55!:up:

Thanks Pissed ... :2thumbs:

 

[Five Five]

Congrats on getting her running Five...:2thumbs::2thumbs:

Thanks Brew ....:2thumbs:

 

[Five Five]

55,
There is a radius machined on the pinion shaft where the drive gear butts up against.If the gear is installed wrong it can set up a stress riser,which will lead to a crack around that part of the pinion shaft......(chamfer needs to face radius).:2thumbs:
John

John ..... with that said I'm going to open it up just to double check ..... thanks for the learning opportunity...

:2thumbs:
"Five"

 

[KnotSo]

Good to hear you got her back together and we all look fwd to seening the vid and hearing it run

 

[Th3InfamousI]

55,
There is a radius machined on the pinion shaft where the drive gear butts up against.If the gear is installed wrong it can set up a stress riser,which will lead to a crack around that part of the pinion shaft......(chamfer needs to face radius).:2thumbs:
John

I realize I am digging up bones here but wanted to put a picture to this as its very useful information. I don't see this mentioned in the service manual anywhere.

Chamfer needs to face inside of motor. The Pinion Shaft has a radius on the inside.

Radius:

Chamfer on gear faces radius on pinion shaft

Wrong Side or facing out.

 

[Mr. Wright]

Every bit of information helps. I'm thinking about doing my engine this winter. It sucks a qt of oil at about 2500 miles.