How do I remove my hydraulic pump?

[timcote42]

Greetings lubeheads. I am trying to remove the hydraulic pump that is currently attached to my rear PTO on my Kubota B7100. It runs the backhoe, and I'm supposed to put it on and take it off when attaching or detaching the backhoe. Just bought the rig and wanted the backhoe off quickly, and knew I was going to change up all the fluids, so I just removed the hoses and defered the pump removal (which initially seemsed tricky) to another day. Today is the day.

As you can see in this photo, the pump is coupled to the pto shaft with an odd cylindar and a fitting that look like an attachment pin. As you cannot see in these photos, there are also two set screws, about 5/32". I have tried to remove these set screws and found them completely frozen and I believe I have now stripped out the hex fittings. I suppose I will have to drill them out and re-drill/tap new holes for new set screws.

But this odd "attachment pin" thing has me baffelled. It doesn't push in, doesn't pull out, doesn't seem to turn, at least not without snapping a toothy vicegrip on it (which I really don't want to do right now). The back side of the pin seems to be a blind hole. What exactly is this and how does it work? Given it's location, I am sure that this thing is key to my removing the hydraulic pump, but before I exert any real force on it (a bang in with a hammer, a vicegrip pull out or turn), I though I'd ask someone who has seen one of these things before.....

Tim

 

[Farmerford]

Tim:

I sure looks to me like the typical spring loaded cross pin on PTO quick disconnects. Mine often get stuck and a few taps with a hammer usually loosens them up. They are usually tapered and the spring can push them into the groove in the shaft pretty tight over several hundred thousand turns.

You said the other end is in a blind hole. That's probably where the spring is, although I am not sure how it could be assembled through the small hole where the pin sticks out.

I would squirt some rust dissolver (PB blaster or your favorite) on it, tap gently with a hammer, and go away for a day or so to let the stuff work. Then tap the end with a hammer as hard as you can without mushrooming it. It should loosen and travel into the coupling so you can then pull the coupling off. Of course, if the set screws were rusted, and the pin is rusted, the coupling may be rusted on to the PTO shaft, pump shaft, or both. That will call for heating the coupling or more drastic action like cutting it off with an oxy-acetylene torch or grinder.

Good Luck.

 

[kennyd]

Give it some gentle taps with a hammer, you should be able to push the pin in and then slide the unit off the shaft.

 

[timcote42]

Gents,

Okay, thanks for the advice. I did as you suggested, gentle, then with increasingly fourceful taps with the hammer. Slowly, the pin retreated into the housing of the coupling, and it's now flush. A cruddy rust slurry (admixed with WD40) came out the other blind-hole end. The pin is now flush with the housing; it does not slide back out. Needless to say, the hydraulic pump did not jump into my arms...i feel no wiggle.

So I'm going to let WD40 work its overnight majic, but failing that, what do you suggest as a next step? I REALLY don't want to go the oxyacetyline torce route, especially as I don't yet own one. Can the pin be drilled out if necessary? Suggestions?

Tim

 

[blueriver]

Gents,

Okay, thanks for the advice. I did as you suggested, gentle, then with increasingly fourceful taps with the hammer. Slowly, the pin retreated into the housing of the coupling, and it's now flush. A cruddy rust slurry (admixed with WD40) came out the other blind-hole end. The pin is now flush with the housing; it does not slide back out. Needless to say, the hydraulic pump did not jump into my arms...i feel no wiggle.

So I'm going to let WD40 work its overnight majic, but failing that, what do you suggest as a next step? I REALLY don't want to go the oxyacetyline torce route, especially as I don't yet own one. Can the pin be drilled out if necessary? Suggestions?

Tim

Thats good that the pin went in, it does NOT need to be drilled out, once it went in it has a notch that matches the PTO shaft to slide on and off, the pin also holds it on!! I can assume that if that much "cruddy rust slurry" came out, more than likely it is rusted to the PTO shaft, without heat, you may have to try and get a lubricant around the PTO shaft into the area where the housing meets the shaft and fiqure a way to tap, pull, or whatever. Just keep working it till its loose, heat may be your only solution. Good luck!

 

[kennyd]

Sounds like the coupler is rusted on the PTO shaft, your going to have to keep working on it...Might try PB Blaster, it works much better than WD40 IMHO.

 

[timcote42]

Darn, another one of those slow, dragged out jobbies. Okay, I will try to fabricate some kind of a "puller" for this thing, try out the PB Blaster (whereever I can find that!) and perhaps go out and buy me a torch set-up so I can heat the thing too.....will keep you informed....Thanks to all! Tim

 

[kennyd]

Be careful with the heat, there are seals in the pump and the tranny!

 

[blueriver]

Be careful with the heat, there are seals in the pump and the tranny!

Those seals are delicate. Really, I believe with lube, tapping, pulling wiggling and just keeping after it, it will work loose. If not be very carefull with the heat.

 

[timcote42]

Those seals are delicate. Really, I believe with lube, tapping, pulling wiggling and just keeping after it, it will work loose. If not be very carefull with the heat.

Okay, okay---tap, pull, wiggle. I could devise a cute puller out of plate aluminum and 5/8" steel bolts too, if it comes down to that. Believe me, I'd prefer to avoid the tourch bit. Any suggestions on the best outlet for PB Blaster? I've not seen it at Home Depot....Tim