Post hole digger gearbox stripped?

[zing]

Hey all, hopefully some of you have enough experience with gearboxes (PHD or otherwise) to be able to tell me if this gearbox is pooched or not. I gave it a try the other day and the drive axle is turning fine, but the auger stops as soon as it is touched to the ground. With the tractor turned off and the PHD in the air, I can turn the auger by hand and the drive axle doesn't move. There is a distinct clicking sound from the gearbox while I do it. I am not sure if that means the gearbox is totally stripped, or if there is something else going on, like a pin or something that is needed to engage the PHD. It is a John Deere 100 model PHD. I am linking a couple videos that show what is happening, if you have high speed and are able to view them. Any advice appreciated.

Unfortunately I don't ahve any good pics of it, but here are a couple of bad ones. I won't be able to get any better ones for a couple weeks since it is at the farm, and I am not.

Thanks

 

[zing]

It would only let me link one video in the post, so here is the second one. In this one you can hear the clicking sound as I turn the auger by hand.

 

[quicksandfarmer]

Usually there is a shear bolt that protects the gear box. My PHD has two, one on the PTO shaft before the gearbox and one between the auger and the gearbox.

A shorn shear bolt would act like that, enough friction to turn when there's no resistance but not enough to do any work. Would also click once per revolution.

 

[pmsmechanic]

Google john deere parts and look for catalog number 9969. It will give you a good idea of what to look for.

 

[zing]

Interesting. Good tips guys, I will look into that. Thanks for responding.


*** Edit, just had a look as per pmsmechanic's suggestion and found the ownerrs manual here in downloadable format. Excellent. http://manuals.deere.com/cceomview/5BP960380B_19/Output/5BP960380B.pdf

 

[Sawyer Rob]

It "sounds" like the gears are gone to me... Well, gone or have moved far enough apart to be slipping...

Take the bolts out of the top of the gear box and have a look...

SR

 

[buickanddeere]

There are low rpm, high torque direct drive hydraulic motors for post hole diggers. No shear pins, backs out from jams and no pto shaft in the way.

 

[zing]

Yeah Sawyer Rob, now that I have the parts manual with the exploded view of the gearbox, that looks like it will be my next step.

Buickanddeere, I have seen hydraulic PHD's, but i hadn't even considered trying to convert this one over. Without even looking into it I am pretty sure that is not in the budget. If I can't get this working with a few gearbox replacement parts from John Deere (hopefully) then I think I will be back to diggin by hand for a while. If I get to the point where I have to replace it, then I will look into the cost of a conversion from PTO driven to hydraulic as well.

Cheers

 

[buickanddeere]

I doubt that Deere built the post hole digger. If Deere doesn't stock the pieces, the identical part maybe from some jobber? Landpride, Lowery Machining,Shaver,Danuser and Harleman come to mind. My first TSC post hole auger digger was made by various lowest bidders to similar specs. To get it working after hitting stones. We had to fabricate the 1-1/2" to 2" sleeve from the gearbox to auger. The replacement shearpin pto yoke had to be re-drilled to line up. The factory auger's cutting tips were bending and needed heating and pounding back into alignment.

 

[Mace Canute]

The first thing I would suggest as a quick and relatively easy check is to pull the 1/2" pipe plug (#11 on page 48) and see what the gear oil looks like. If the gears are worn or a bearing has failed there should be a considerable amount of very fine metal in the oil making it look silvery. If there is metal in the oil you will have to replace all bearing even if they look ok because they definitely will have been damaged. This is in addition to any other damaged parts that need replacing.