PTO Clutch

dieselsnowmobile · #1 09-15-2009, 09:34 PM

New here, and I just bought a CC 104 that I bought to mow the .25 acre yard, so not huge. I will also use it to plow snow once I get a blade. I first learned how to mow on a 104, so a little history with the 104.

When I bought it, the PTO had no ceramic piece and no belt from the engine to the deck. I saw the they also make a brass piece instead of the ceramic, so I rigged one up using a brass barbed pipe. When I went to disengage the PTO clutch, the the button on the PTO kept turning along with the pulley and ate my brass right up. Is that the way it is supposed to work? I have never seen one in working condition. I cannot imagine that the button would keep turning when the PTO is disengaged, otherwise the ceramic piece would wear out incredibly fast. I have a feeling, the PTO clutch is shot.

What is the best way to fix it if it is in fact shot? I am some what mechanically inclined (change the head gasket on my car is about the biggest job I have ever done). Can I just buy a $50 PTO clutch rebuild kit on eBay and bet set? Or would I be better off buying a rebuilt PTO clutch for $175ish?

Thanks.

MBounds · #2 09-15-2009, 09:46 PM

Dieselsnowmobile: You can easily purchase a 759-3490 PTO repair kit. However!! The kit does not contain a thrust button (that's the one in the center of the pulley) nor does it contain the carbon-fiber wear button (found on the lever and presses on the thrust button). These must be purchased separately at extra cost. None of this totaled will get any where near the price you quoted. The repair kit comes with instructions and a gauge to adjust the tri-spring. Take a good look at the OCC Tech section and print off yourself a copy ot the IH self-locking bearing instructions. The PTO is installed on one of these. Not to mention that there is lots of experienced hands around here to help..just ask..

Myron B

Yosemite Sam · #3 09-15-2009, 10:03 PM

Yes the button in the center of the PTO (Thrust button) turns even after the PTO has disengaged (if the motor is turning then so is the button).

Factory Wear buttons are not ceramic but a sort of fiber (I'm sure someone here knows exactly what kind of fiber, but I do not) I believe that the "aftermarket" buttons are bronze not brass. Someone on one of the other forums has been experimenting with bronze bolts as wear buttons, and if I'm not mistaken, he had had pretty good luck so far.

Often times the wear buttons wear out quickly because of misadjustment, this comes in several forms, off to one side, too high/low, too much tension, or misadjusted PTO, jus t to name a few. Start by eyeballing where the buttons meet, look for misalignment when the pto is in the "not running position there should be a little air gap between the two. Hope this helps head you in the right direction.

ajgross · #4 09-15-2009, 11:57 PM

Just to add a bit, it is usually recommended that when you are not using the pto for anything, if at all possible, remove the belt and leave the pto engaged. That way the buttons are not in contact with each other, thus greatly extending the life of the buttons.

AJ

dieselsnowmobile · #5 09-16-2009, 08:19 AM

Thanks for the replies, I ordered 759-3490 along with thrust and wear button. It looks to also be missing a screw so I ordered that as well. I have searched this forum and read about about the PTO as much as I can. No off to buy PB Blaster and soak it until the kit comes in.

wshytle · #6 09-16-2009, 10:19 AM

Yosemite Sam - You stated that the thrust button is turning if the engine is turning. I have to disagree. When you disengage the pto by pressing the wear button against the thrust button it should stop therefore not grinding up the wear button. When you engage the pto the wear button should end up not touching anything therefore not grinding up the wear button. Alignment is important but not critical. If the thrust button and wear button are "off" a little it will find exact center automatically and as long as the wear button doesn't turn in its mounting hole in the rockshaft lever it should remain aligned.

Dieselsnowmobile - It's not a difficult job at all. There has been an extensive discussion on the matter on another website recently and everything was covered at least once. When you get the set screws out you can use a long, blunt punch at an angle on the carb side to tap, and I mean tap, the pto off of the crank. Keep turning the crank by hand and position the punch in the pulley lip of the pto. Do not hit the punch, just a good tap. It may take quite a few taps but keep rotating and tapping. It has worked every time for me.
Good luck

Wayne

Rhoderman · #7 09-16-2009, 10:37 AM

I just fought this battle last week.
There are two setscrews per hole. They are both pointed setscrews.

I would strongly recommend using either a 1/4-20 bottoming tap, or a 1/4-20 plug tap ground down so the first cutter is full thread. Then run that down onto the top of each setscrew to clean the rust out of the threads, down to the setscrew.

Use your best allen wrenches, or buy a very expensive good set. You will need the 1/8" one, and you only get one chance to slip. I have a set of HoloKromes that are incredible.

If you are successful getting the first of two setscrews out, run the tap down the threads again to scrape the rust out. On mine, the first one was in/out many many times at maybe 1/4 turn until I got it out. The tap made that part much easier.

You will discover that the point of the setscrew kind of wedges the sealed bearing into the pulley by running into the edge of the bearing. For that reason, if you have to drill it out, you will wreck your #7 drill bit. A #7 is predrill for 1/4-20.

The advice about carefully walking it off the bearing is good. On mine, I used a piece of 1/2" rod and alternated sides, carb, then starter-gen.

If you take off your hood and heavy cast iron front support, you will make your life a LOT easier. Beware that front support is VERY heavy!

Good luck! Don't get in a hurry, and if you have problems, post here. Someone will help you. They did for me.

Jim

wshytle · #8 09-16-2009, 01:14 PM

Rhoderman - I seem to be the "disagreer" today but I am speaking from experience. There are two set screws but only one has a noticable point. IH installed a larger set screw in the hole first and this is the pointed one. The point is designed to wedge behind the back corner of the bearing housing forcing the bearing forward (or pto backwards) against the lock ring inside the pto pulley. The second set screw is about 1/2 the length of the first and is there to lock the first one. It doesn't have the pronounced point, just a semi-flat point. I also use a very small amount of blue locktite on both set screws. Having said that, I have found different after market set screws and also set screws in the wrong order. I also put a small amount of grease on my finger and run it around the outside of the bearing before slipping the pto on. I mean a very small amount. I do this for ease of future removal. It slows down that fine rust that causes forum talk.

I like your advice about chasing threads. I have made a set of "thread chasers" from grade eight bolts by cutting and filing the threads and use them all of the time. Of course taps are probably the best but my bolts are easy to start then I finish off with a good blast of air.

I guess I'm a stickler for detail but one wrong bit of advice can really cause headaches so I simply try and back up and stick to what IH did in the first place. After all, their way has been proven with time.

Good luck to all....Wayne

wshytle · #9 09-16-2009, 01:23 PM

Also to everyone with the pleasure of mech. pto situations.

You need to purchase an extra 7/16" open end or combination wrench. Grind the sides of the open end to the thickness, or a little less than the thickness of the jam nuts that lock the thrust lever bolts (3) in on the backside of the pto. Dedicate this wrench to a pto repair box and you won't regret it. You can use any other 7/16" wrench for the outside nut but the inside nut is hard to hold with a standard thickness wrench. I even painted my wrench to keep myself reminded to leave it with the pto adjusters, etc.

Just another two cents worth . . .

Rhoderman · #10 09-16-2009, 10:16 PM

Quote:

Originally Posted by wshytle

Rhoderman - I seem to be the "disagreer" today but I am speaking from experience. There are two set screws but only one has a noticable point. ...

No worries Wayne. Thank You for correcting my misinformation. I was only posting what mine had, and, as I should have known, it was wrong. I actually do recall seeing the remnant end of a cup point setscrew when I was cleaning up. That was from one of the two in line that I drilled out. I spent a ton of time removing the two (in the same hole) pointed setscrews, so I thought they were all that way. It makes sense that they would chase a pointed with a cup point. After removing more pieces, I was able to recognize that someone else had been in there before me, but after the factory. If you agreed, there wouldn't be any point in all this, now would there? Thanks, and you are welcome to disagree with me any time sir!

Quote:

Originally Posted by wshytle

....
I guess I'm a stickler for detail but one wrong bit of advice can really cause headaches...
....

I couldn't agree with you more there, Wayne. I had no intention of leading anyone astray.

Here is my post last week showing my fun:
http://onlycubcadets.net/forum/showthread.php?t=1584

Regards,
Jim