122 PTO Clutch Removal

[ironman]

Originally Posted by ironman

I think I read somewhere that just tapping the center button with a hammer while you put rotate pressure on the basket, it will move a little bit with each tap. Never tried it though.

Originally Posted by Jeff in Pa

I have tapped the center button on the PTO with a dead blow hammer to get the PTO to rotate a little at a time,

I think I read somewhere else that "Great Minds Think Alike"

[ironman]

Originally Posted by Nailhead

Thanks everyone!

I forgot to ask: where do you get the setup gauge for the clutch?

If you are good with a ruler, tin snips, and a file you can make your own out of some light guage aluminum.

WF upper, NF lower

[mortten]

Xtreme Motor Works, CC Specialties, or it comes with the rebuild kit.

[coakes00]

I cut one out of an old license plate with my Dremel.

Just make sure you have even tension on all fingers. I had one that became a little loose after tightening the jam nut and within a min of being on the motor it started to rattle pretty bad. It didn't come apart on me but if I wouldn't have checked it probably would have just like it did on the PO before I got it.

[Nailhead]

Confession time: I had the PTO engaged when I was trying to start the tractor the other day... Good thing, though: I would have gone on my merry way & probably lost that bolt & finger in the grass.

Ironman: thank you for the suggestion & prints, but I hang gutters for a living & reserve my weekends as a "tin snip & light gauge aluminum-free" time period. A time-out, if you will.

Mortten & Coakes: Thanks for the info-- after I get coffeed up, I'm going to go dig into this thing & see what parts I'll need. I'm starting to see a use for Loctite on these bolts, but I'll have to wait until I get the PTO apart to see how relevant that might be.

[Nailhead]

Got one set of set screws out, but the other two are still in there-- it seems one was pre-stripped, and the other cammed out when I was trying to get it undone. I used a nearly-new Bondhus T-handle wrench, so I'm confident tool quality wasn't the issue.

Between playing password games with this website, and wearing out a new cobalt drill bit trying to drill out one of those screws (I got about 1/8"), I am thoroughly disgusted with this little yellow & white time/money pit. Drilling doesn't look like it's going to work (cobalt is about the best I know of), so the only option seems to cut it off with an OA or cutoff tool. If I do this, I'll have to buy a new PTO, which pretty much exceeds the amount of money I want to put into this thing.

Any further suggestions, because destruction of that PTO means the whole mess gets pushed out the door, and to the curb.

[Jeff in Pa]

Set screws are made of tough material. You will need high quality drill bits and a variable speed drill plus oil for cooling.

Slow speed is the key here. High RPM is only going to work harden the set screws and make your life even more difficult.

Let me know if you have the engine out or if it's still in the tractor before I do a write up.

Jeff

[Nailhead]

Originally Posted by Jeff in Pa

Set screws are made of tough material. You will need high quality drill bits and a variable speed drill plus oil for cooling.

Slow speed is the key here. High RPM is only going to work harden the set screws and make your life even more difficult.

Let me know if you have the engine out or if it's still in the tractor before I do a write up.

Jeff

I used to work in the oilfield-- I've drilled hundreds of holes in steel, using a slow speed & oil as a cutting fluid. You can tell where the sweet spot is speedwise by the feel of the bit biting, and the shavings produced. NONE of that happened in this instance, and doesn't seem likely to, because I varied drill speed all over the place, and got nothing. As I mentioned, this was an essentially new, sharp cobalt bit. Ten minutes, and 3/32" ruined it, oil & all. There aren't enough cobalt drill bits in town to support that rate of success.

As for a write up, I have no idea what you mean.

Thanks, Jeff. I'm going to sleep on it, and see if I have any further interest in this thing when morning comes around.

Chris

[Jeff in Pa]

Originally Posted by Nailhead

I used to work in the oilfield-- I've drilled hundreds of holes in steel, using a slow speed & oil as a cutting fluid. You can tell where the sweet spot is speedwise by the feel of the bit biting, and the shavings produced. NONE of that happened in this instance, and doesn't seem likely to, because I varied drill speed all over the place, and got nothing. As I mentioned, this was an essentially new, sharp cobalt bit. Ten minutes, and 3/32" ruined it, oil & all. There aren't enough cobalt drill bits in town to support that rate of success.

As for a write up, I have no idea what you mean.

Thanks, Jeff. I'm going to sleep on it, and see if I have any further interest in this thing when morning comes around.

Chris

Chris, You say "cobalt drill". Cobalt brand or as ingredient ? You need a high quality drill, not what they sell in the local hardware store. Precision Twist or Guhring would be my first choices.

For write up , as in how to do it.

~~~~~~~~~

Turn the engine so the hole is in a location that is comfortable for you to both drill and to stay centered. You said you got one pair of set screws out already. Use a 1/4" or "F" ( .257 ) drill to see where the threads start. If there is room, use that drill to give a good centered area on the set screw to start drilling.

I would start with a 3/16" ( .1875 ) drill and run it SLOW. Plenty of lubricant and steady , even pressure. I would NOT go to the tap drill size until you have drilled thru all the stuck set screws. Get a puller and pull the PTO off. there will only be a little bit of the set screw major diameter left and that will deform enough to come over the bearing.

Once it's off, then drill will the proper tap drill size. That's how I did the one on my first 125. I used three drill bits on each hole. ( actually the equivalent of three drill bits as I sharpened them. As a machinist for over 35 years, I have a good eye for hand sharpening )

Clean the threads with a good quality tap. ( once again not the junk they sell at the hardware store )

The tap drill size for 1/4-20 NC is a #7 drill ( .201 ) but use a 13/64 ( .203 ) if you don't have numbered drills.

Good luck
Jeff

[Nailhead]

Originally Posted by Jeff in Pa

Chris, You say "cobalt drill". Cobalt brand or as ingredient ? You need a high quality drill, not what they sell in the local hardware store. Precision Twist or Guhring would be my first choices.

For write up , as in how to do it.

~~~~~~~~~

Turn the engine so the hole is in a location that is comfortable for you to both drill and to stay centered. You said you got one pair of set screws out already. Use a 1/4" or "F" ( .257 ) drill to see where the threads start. If there is room, use that drill to give a good centered area on the set screw to start drilling.

I would start with a 3/16" ( .1875 ) drill and run it SLOW. Plenty of lubricant and steady , even pressure. I would NOT go to the tap drill size until you have drilled thru all the stuck set screws. Get a puller and pull the PTO off. there will only be a little bit of the set screw major diameter left and that will deform enough to come over the bearing.

Once it's off, then drill will the proper tap drill size. That's how I did the one on my first 125. I used three drill bits on each hole. ( actually the equivalent of three drill bits as I sharpened them. As a machinist for over 35 years, I have a good eye for hand sharpening )

Clean the threads with a good quality tap. ( once again not the junk they sell at the hardware store )

The tap drill size for 1/4-20 NC is a #7 drill ( .201 ) but use a 13/64 ( .203 ) if you don't have numbered drills.

Good luck
Jeff

It's part of a cobalt steel bit set I bought at Fastenal several years ago, which has always performed really well drilling steel. I had started with a 9/64 for quicker drilling, and because it looks to be the size of the screw minus the thread depth, if that makes any sense.

I've already got a #7/1/4-20 combo that I used for grounding equipment in my previous life, so I got that going for me.

Thank you very much for the write-up-- I really do appreciate it. Tonight, I'm going to forget about the little parasite, and tomorrow (or whenever), I'll decide whether I want to devote further time/energy/money/garage space to it. There's a National Guard training camp in eastern Wyoming that loves stuff like this for their gunnery range, and that continues to be tempting.