Alpha 1 upper gear shimming

[NHGuy]

I put a new input yoke on my drive last winter because it had a rough seal surface. It would not hold pressure. Now the drive whines more than before. I thought that since I was using the same gear cluster there would be no need to redo the shims. Apparently I am wrong. I thought that since I would be using the same gear cluster I could just put it back together and set the preload. Apparently something isn't the same though. So I am rechecking the gear spacing and while doing the reading I noticed there can be a standard drive gear or a heavy duty gear that is marked G-7 on it's inner surface. I also see that the standard gears have an index mark on them and the HD gears do not. Apparently you just assemble the HD gears to any tooth.
The HD gear uses a different feeler gauge than the standard gear. So, if the gear has an index mark is it standard? Or should I remove it and look?

 

[achris]

Re: Alpha 1 upper gear shimming

As long as you set the pre-load correctly and the cover nut and top cover screws were tightened up correctly, the shimming should NOT need to be changed.

As for indexing, that only applies to the 1.65:1 gear set. You should have 1.50:1, unless someone has changed it.

Check to make sure it's full of oil.

Chris......

 

[NHGuy]

Re: Alpha 1 upper gear shimming

That's what I thought, but I just checked with the gap tool and the space is too small. Bet I dropped a shim when I had it out. My workspace ain't exactly a scientific clean room.
There is a little bit of a track visible on one side of the teeth, hopefully proper shims will quiet it.
Oh and the oil was fine when I drained it. Still kinda green.

Yup, I get it about the indexing, I did see that was on the 1.65's. Just forgot about that while reading further.
And I have 1.47 gears according to a sticker that was on the drive.
Thanks for the knowledge.

 

[achris]

Re: Alpha 1 upper gear shimming

If you dropped a shim, the gap would be too big....
And the oil question was more about quantity than quality...

 

[Bt Doctur]

Re: Alpha 1 upper gear shimming

You dont list the year of the drive. If you removed the gearset by hand, then there is no pre-load setting. just torque the nut to spec.
If you needed a puller to remove the gearset,, then you use the "rolling torque" method for assembly

 

[NHGuy]

Re: Alpha 1 upper gear shimming

Yes, it was rolling torqued because it did not have the early type spacer in the center of the gear cluster. So are you saying that if it slides out it is torqued to the higher value? That could be my issue. Mine did slide out without a puller. Then I did the rolling torque thinking it was that setup. My #6 manual doesn't use that as a determining fact unless I missed it. I'll read it again.
If it needs the higher torque it will move the drive gear back and leave more room for my gap gauge. I might not need shims after all.
And I respectfully disagree about the gap Chris. I'm talking about the shims that go in the front of the drive before I put the horizontal drive gear cluster in. Fewer shims allow the cluster to go farther in , right?

 

[Bt Doctur]

Re: Alpha 1 upper gear shimming

Nope, if the gearset slides off the shaft you have an early gearset that used the inner small spacer and the outer large spacer. then you just torque the nut.If the gearset was replaced with the newer style that needs to be pressed on you are told to throw the inner spacer away and use rolling torque method for re-assembly.

 

[achris]

Re: Alpha 1 upper gear shimming

..
And I respectfully disagree about the gap Chris. I'm talking about the shims that go in the front of the drive before I put the horizontal drive gear cluster in. Fewer shims allow the cluster to go farther in , right?

Respect earned. Those shims, yes... less gap.

 

[achris]

Re: Alpha 1 upper gear shimming

Nope, if the gearset slides off the shaft you have an early gearset that used the inner small spacer and the outer large spacer. then you just torque the nut.If the gearset was replaced with the newer style that needs to be pressed on you are told to throw the inner spacer away and use rolling torque method for re-assembly.

What if it's been diss-assembled in the past and whoever did it didn't understand the way the 2 different bearing packs work, throw away the inner spacer and used the rolling torque method?

OP. you need to identity the bearing and gearset and (if necessary) obtain a new inner spacer...

Chris...

 

[NHGuy]

Re: Alpha 1 upper gear shimming

I had that thought, will have a look. Could have been there all along...I will report.