Posthole Digger Danuser F8 problems

Urban · May 22, 2020

I just bought an old used Danuser F8 and used it for the first time yesterday. I needed to drill four holes. The first three went great but on the fourth, when I lowered the 3 point to start the hole, the auger quit spinning. The PTO was spinning as was the auger but as soon as I put down pressure on the auger it quit spinning although the PTO continued to spin. The bolt that holds the auger on the shaft coming from the gear box is not sheared unless in sheered in the middle and neither side of the bolt came out. The auger did have a small leak when I bought it right where the shaft comes out of the gear box but in reading about these diggers, that seems to be a common issue with old ones and you should just add grease/oil as needed. I noticed that it was leaking worse at this point and could tell that there was water in the gear box by the milky look of what was coming out. One last thing... when I parked it and put the 3 pt down, I went around and rotated the auger by hand. It would turn maybe a third of a turn and then slip a bit, move a third and then slip, and so on.

I have not been back out to check it out any further, but assuming the pin didn't sheer, what else could be the cause? Any thoughts or suggestions will be appreciated.

Alan W. · May 22, 2020

Its the shear bolt. Ive had mine shear but not fly out.

Alan W. · May 22, 2020

Try turning the shear bolt with a wrench. Ifn only one side moves thats the problem for sure.
Sounds like water has got into the gear case. You need go drain it and replace.

Urban · May 23, 2020

I will try both tomorrow and report back. Hopefully, that is all that it is.

aczlan · May 23, 2020

Alan W. said:
Its the shear bolt. Ive had mine shear but not fly out.

Yep, especially if the slop around the bolt in the hole and you are using a grade 2 bolt, the end of the bolt can "smear" and keep the two ends from falling out.

Aaron Z

Urban · May 23, 2020

Thanks for the info. It is actually a grade 5 bolt. I was going to get a 2 but everyone I talked to said go with a 5. I am encouraged by the replies so far that the shear pin is the problem. I will find out later on today.

Urban · May 23, 2020

Well, unfortunately, it was not the shear bolt. Does anyone have any other suggestions? Could it be bearings or either of the gears?

RickB · May 23, 2020

If the input shaft turns and the output shaft does not the next thing is to remove the gearbox cover. You will not know anything until you take it apart.