# JD 726 drive does not engage.



## Insanity

I have a JD 726 that will not engage the drive when the clutch handle is gripped. Everything in the drive compartment seems to be in place and able to move. No belts are loose or broken.

Looking for any suggestions?


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## micah68kj

Insanity said:


> I have a JD 726 that will not engage the drive when the clutch handle is gripped. Everything in the drive compartment seems to be in place and able to move. No belts are loose or broken.
> 
> Looking for any suggestions?


What is the condition of your drive disc? The belts can be great but if your disc is bad it ain't gonna budge. If it's questionable you'll want to clean it off and maybe even take some sand paper to it to rough it up a bit. Also clean the drive plate off.


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## Normex

micah68kj said:


> What is the condition of your drive disc? The belts can be great but if your disc is bad it ain't gonna budge. If it's questionable you'll want to clean it off and maybe even take some sand paper to it to rough it up a bit. Also clean the drive plate off.


And I may add if I may to check for the rod or cable adjustment connected to your drive handle, they can be tightened to have your friction disk press harder against the drive plate. But as Micah noted check your friction disk condition first, if you see lot of rubber near the friction disk and if the rubber ring is near the metal ring holding it then it's time for replacement.
Good Luck


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## jtclays

Agree to check the friction wheel to drive platter connection first. You say the belts are fine and accounted for. 
Looking inside the belly at the friction wheel and drive platter. When you squeeze the clutch handle at the handlebars, do the friction wheel and platter meet? Without squeezing they should be 1/16" apart at rest per the manual. You said everything inside the drive moves.
When you select a gear/speed, is the friction wheel moving sideways away from the center of the platter? It should.
If so, select say "3" and start the engine. Engage the clutch handle and you get no movement, try pulling up on the handle bars to clear the wheels off the ground. Do they turn now? If so you may have lost a key in the hub the friction wheel attaches to, or the nut is not snug on the friction wheel. Check out the second diagram below and see 10, 11, and 4. Easy way to check is with engine off, grab hold of the inner chain that hooks to the friction shaft sprocket on the opposite end of 11 (use a heavy glove or rag). Try turning the friction wheel either way with your other hand. The chain and sprocket should follow your movement. If they don't that 10 key could be shot.
If that checks out, engine off, clamp the drive lower pulley tight in a way that wedges the clamp/visegrip against the body or frame. Reach inside the belly area and try to rotate the platter that the friction wheel mates with. If you can turn that platter/plate you may have lost the key inside the plate shaft (first diagram, see 18 and 19). Or the set screw in the drive pulley (first diagram see 25, 26, and 27).

Another spot to check is just to the right of the differential (inside the belly along the wheels axle) for a roll pin or on some models a bolt (see 3rd and 4th pic) That pin/bolt needs to be there for the axles to rotate under load. 
Another off chance is your big wing nut on the left wheel is spun way out on it's threads, righty tighty that up snug and try a running engine clutch handle engagement if you find it loose.
Can you snap some pics of the belly area and the belt area (belt cover off) Someone may be able to see something completely missing, or in the wrong place that will solve your issue. Just FYI


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## Insanity

Here is the belt area. Both belts are in place. The loose one is the one that engages the blades.


Here is the compartment. Both chains are on the sprockets.


A close up of the friction plate. There does not appear to be any excessive residue on the plate. The rubber is a bit cracked. When I squeeze the handle, it does make good contact with the plate and I can not move it by hand.



A close up of the chains.


A close up of the belts in the compartment.


To my eyes, the belts and chains and friction wheel seems okay. The differential might be the next place to look then?


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## db9938

Insanity said:


> Here is the belt area. Both belts are in place. The loose one is the one that engages the blades.
> 
> 
> Here is the compartment. Both chains are on the sprockets.
> 
> 
> A close up of the friction plate. There does not appear to be any excessive residue on the plate. The rubber is a bit cracked. When I squeeze the handle, it does make good contact with the plate and I can not move it by hand.
> 
> 
> 
> A close up of the chains.
> 
> 
> A close up of the belts in the compartment.
> 
> 
> To my eyes, the belts and chains and friction wheel seems okay. The differential might be the next place to look then?


There appears to be a missing roll pin/bolt in your third picture.


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## jtclays

DB is right, you're missing the roll pin I have shown with the small screwdriver above.
The friction wheel looks like part of the pin is lodged in there so you may be able to use that for a diameter reference
If you have the machine tipped up, you can hold the differential or left wheel and turn the right wheel to locate the hole on the inner axle shaft. You may have a piece of the pin still in the inner shaft. Could be a small bolt and nut too, but the wear/rust pattern looks like it was a pin


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## jtclays

Since you're already in there, you should look at the axle bushings. They'll be right where each wheel hub meets the tractor body and fit in the hole of the tractor body. If worn badly,they will let the axle buck up and down and put stress on that pin you're missing. You can just wiggle the left wheel (chain side) as you have it in the pics and kind of tell. They usually wear in the upper half as the weight of the machine is down and the ground keeps contacting the tires, wheels and axle up. If they are just egged/ovaled at the top, you can try rotating the bushing around in the hole to put the thicker side at 12 o'clock until you can get new. I'd replace the friction wheel after you verify the bushings are OK or replaced, along with your pin obviously.


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## db9938

Are the axles just sleeves?


And good catch on the pin in the rubber. Missed that one totally.


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## micah68kj

I'd still replace that rubber drive. It looks like it's pretty far gone and with the roll pin stuck in it... .


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## jtclays

DB, Yes, the part you see cross way in the belly is a sleeve and not the actual axle. It's a complicated hook up as there are gears inside the differential connected to flats cut on each side of the real axles. The left being shorter than the right and the wing nut on the left wheel controlling the two wheel drive versus one. That pin makes the right the primary drive taking the rotation power from the spinning differential.
When everything is connected properly, it runs just like a cars rear end. Or seizes if not maintained


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## Insanity

The roll pin is indeed missing, and I was able to thread a pipe cleaner through the hole.

I do not think it was in the friction wheel, as when I went to grab it with a pair of needle nose pliers, it did not have the metal on metal contact I was expecting and I pulled off a bit of rubber. Might just be an artifact of the rubber molding as there was another similar looking bit on the same side of the wheel, but opposite location.

I measured the other roll pin at 3/16 inches, perhaps some can verify that. I was going to look around for ordering two new pins as I may as well replace both, and the friction wheel.


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## jtclays

I think they're just standard roll pins you can get in the drawers at Lowes/HD/Ace. That's one cool thing about the old blowers, no metric stuff.
Looked on JD parts and they call out the "groove pin" as 3/16''x 7/8" (that seems too short to me) and the bolt/screw as .190" x 2". I can't remember if i got them at Ace or Lowes, but I bought an assortment pack of roll pins. Use them on lots of stuff.


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## Insanity

I did see some 3/16 inch groove pins at Tractor Supply, but they were 1.5 inches long, thought that might be too long. Upon measuring the diameter of the axle at 7/8 inches, I was probably correct.

I will see about getting them at Lowes and see if that at least fixes the engaging drive correctly. At least I will know if that problem is fixed.


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## db9938

I may be wrong here, but I think you might have been ok with that length. There appears to be quite a bit of room in that location, without much interference. 

I'd just make sure you clear any remnants of the old pin out first.


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## Insanity

You may be right, the length of the one in place on the other side of the shaft is 1.25 inches. At the time though, thought it would have been. Regardless, I will hopefully get a replacement tomorrow.


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## jota21

Hello,
Sorry for dredging up an old thread, but my dad's 826D is having similar symptoms, but the original photos with this solution are missing, so i can't be sure. In this situation it looks like there is some sort of retainer clip that is missing, allowing the shaft with the chain sprocket to slide off of the gears (allowing the grease fitting to slip back into the drive compartment, which makes the drive disengage). I can't find anything about this specific piece on any parts diagram, so any help would be appreciated.

As a very unscientific test, i bent a piece of sturdy wire around the grease fitting, and the drive worked as it should, but i can't imagine that to be the proper solution.

Thanks in advance - Sorry the site wont allow me to post photos since this is my first post.


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## Copper116

Quick question if I may. In your first photo of the pulleys and belts by Insanity.. there is the brake lever showing. The brake lever with the rubber bumper that rides on the large pulley to get it to stop when you release the drive and auger. WHERE does the brake lever "spring" hook to. Not on the lever itself but the other end? My vintage 1032 didn't come with a spring. I have a spring now but can not locate where it hooks to. I can't find a hole, a pin or anything that looks like it would hold the spring. If someone could help me out I'd appreciate it.


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## jtclays

654


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## JLawrence08648

On a different note, that auger belt looks exceptionally loose for being not engaged.

However I agree, the rubber friction disk does look at the end of it's life. If you have a backup machine then keep using this machine. If this it's your only machine, replace the rubber friction disk and the two belts, besides a complete servicing, adjusting, lubing.


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## jtclays

JLawrence, The guy who originally posted hasn't been around in 4 years:surprise:


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