John Deere GP

[Mark-Ia]

Anyone know a place to look for the air intake stack?

Detwiler's in Wi had air stacks

 

[Rob_F]

A common problem with GP's is the locating pin that keeps the operating sleeve inline. The operating sleeve is what the brass clutch fork works off. The pin will get loose and then the hole in the sleeve will wear. The whole assembly will put pressure on the dog-bones and pivot assembly that the adjusting bolts work off, and not allow for a good adjustment or operation.

I took the clutch off again to further diagnose. I’m pretty new to this so bare with me. So is the pin that gets worn the pin that’s located about 4 o clock in the second picture and about 5 o clock right below the operating sleeve in the first pic? The operating sleeve moves in and out smoothly but if I twist it left and right there is quite a bit of play. The hole that retains the pin looks to have quite a bit of play. Is this the issue you’re describing??

 

[Mark-Ia]

I took the clutch off again to further diagnose. I’m pretty new to this so bare with me. So is the pin that gets worn the pin that’s located about 4 o clock in the second picture and about 5 o clock right below the operating sleeve in the first pic? The operating sleeve moves in and out smoothly but if I twist it left and right there is quite a bit of play. The hole that retains the pin looks to have quite a bit of play. Is this the issue you’re describing??View attachment 61041View attachment 61042

Yes, that's the pin that gets loose allowing the operating sleeve to rotate and bind up the dogs that that operate the toggles on the T-bolts. I had a local man take the pin out, made a new one that threaded into the clutch drum and bored the hole in the sleeve to accept the new pin. worked great afterwards. The GP was John Deeres "problem child" with many changes being made during it's 7 years of production.

 

[Rob_F]

Yes, that's the pin that gets loose allowing the operating sleeve to rotate and bind up the dogs that that operate the toggles on the T-bolts. I had a local man take the pin out, made a new one that threaded into the clutch drum and bored the hole in the sleeve to accept the new pin. worked great afterwards. The GP was John Deeres "problem child" with many changes being made during its 7 years of production.

Awesome thanks for the info. So I take it the large gear that holds the collar in place has to be removed?

 

[Mark-Ia]

Awesome thanks for the info. So I take it the large gear that holds the collar in place has to be removed?

Yes

 

[Rob_F]

Yes

I didn’t have a puller big enough for that gear so I brought it in to a machine shop. They were kind of weird about the gear and not being able to get it off. It should be that hard is it?

 

[Mark-Ia]

I didn’t have a puller big enough for that gear so I brought it in to a machine shop. They were kind of weird about the gear and not being able to get it off. It should be that hard is it?

I used a gear puller behind the teeth, with a piece of flat bar ground to fit the center.
might need some heat on the gear.

 

[Rob_F]

So I got the clutch back from the machine shop with a new pin. Everything looks good no more slop in the collar but I can’t for the life of me get this thing to snap and lock to engage. I have to push the hand clutch forward and hold it to make it move, it won’t stay engaged. I’ve tried adjusting the 3 castle nuts and still no luck. Im completely stumped.

I’ve got some play in the clutch linkage pin and in the top bushing of the clutch fork housing. That’s my next fix but it seems like there’s more going on than just that. Any ideas??? I also put in new clutch disks as well.

 

[Mark-Ia]

If the end play in the crankshaft is too tight, the clutch won't engage properly. Loosen the flywheel and move it u
ntil you get .010 endplay.

 

[bc]

Just wondering if this is what a neighbor had around 60 years ago? He would go around his field and it would go pop, a short delay, and then another pop and so on as it went around. Always thought it sounded like a one lunger used in oil field engines. It was kinda like the belt pulley and counterbalance on the other side is what kept it going.

 

[Rob_F]

If the end play in the crankshaft is too tight, the clutch won't engage properly. Loosen the flywheel and move it u
ntil you get .010 endplay.

Well I looked at it when I got home from work and zero end play so I loosened the flywheel and got .10 and still nothing. I took it for a ride after and it seemed like it was engaged harder than it did before but still wouldn’t stay locked. Took it for a lap around the neighborhood and by the time i got back to the house it barely moving because of slipping. I don’t get it.

What actually makes the snap in the clutch and holds it engaged?

 

[wore out]

Well I looked at it when I got home from work and zero end play so I loosened the flywheel and got .10 and still nothing. I took it for a ride after and it seemed like it was engaged harder than it did before but still wouldn’t stay locked. Took it for a lap around the neighborhood and by the time i got back to the house it barely moving because of slipping. I don’t get it.

What actually makes the snap in the clutch and holds it engaged?

''What actually makes the snap in the clutch and holds it engaged?"

The clutch "dogs" snap over center and have to be tugged the opposite way to snap to the disengaged position.

Look at which way the "toggles" are angled in either position. In the engaged position the "dogs" can't move any further and the "only way out" is when they are tugged overcenter to the "disengaged position".

And I see NO connection of needing 0.010 of crankshaft endplay for that to happen.

Too MUCH endplay can affect clutch operation, tho.

 

[Rob_F]

Just wondering if this is what a neighbor had around 60 years ago? He would go around his field and it would go pop, a short delay, and then another pop and so on as it went around. Always thought it sounded like a one lunger used in oil field engines. It was kinda like the belt pulley and counterbalance on the other side is what kept it going.

Could be but a lot of the old ones sound similar. You can definitely hear each cylinder fire on this one

 

[Rob_F]

''What actually makes the snap in the clutch and holds it engaged?"

The clutch "dogs" snap over center and have to be tugged the opposite way to snap to the disengaged position.

Look at which way the "toggles" are angled in either position. In the engaged position the "dogs" can't move any further and the "only way out" is when they are tugged overcenter to the "disengaged position".

And I see NO connection of needing 0.010 of crankshaft endplay for that to happen.

Too MUCH endplay can affect clutch operation, tho.

Ok thanks for the info… I’ll pull the clutch again and check the dogs out. Maybe they are worn enough they can’t snap? I’m getting pretty frustrated on this clutch. It seems like it should be so simple!

 

[Rob_F]

''What actually makes the snap in the clutch and holds it engaged?"

The clutch "dogs" snap over center and have to be tugged the opposite way to snap to the disengaged position.

Look at which way the "toggles" are angled in either position. In the engaged position the "dogs" can't move any further and the "only way out" is when they are tugged overcenter to the "disengaged position".

And I see NO connection of needing 0.010 of crankshaft endplay for that to happen.

Too MUCH endplay can affect clutch operation, tho.

It’s like it doesn’t even remotely come close to snapping to engage

 

[Rob_F]

Well I’ve have the clutch torn off for about the 25th time in the last few weeks. Still no luck to get it to snap. All I can figure is there isn’t much movement in the clutch dogs when you lock and unlock the collar. How much do they really move??

Also I noticed when I slide the collar to locked position it hits the big c clip underneath the big gear. Is it supposed to ride over top of that? The machine shop broke it when they repaired the alignment pin and replaced it. Seems like this could be the problem and is not allowing the collar to slide completely to locked position??

 

[Rob_F]

I meant snap ring not c clip

 

[Cash4Toys]

Not in anyway gonna say I know anything about a GP clutch, but typically an over-center clutch does not move very much at all. The linkage should get tight just prior to center or linkage inline, then when it goes just over center it will snap in. In a previous post you stated in was slipping, hence the reason your working on it. My assumption is that you have something that is bottoming out prior to getting tension on the plates, and thus allows slippage, and could by why you cant adjust it to snap over center. You mentioned collar and snap ring possibly being an issue, causing interference and you could very well be on the right track. Hopefully someone that knows GP's will be able to help you out.

 

[Rob_F]

Finally got it!! It was the new snap ring the machine shop installed that was not letting the clutch collar fully engage. I took an angle grinder and was able to make it flush so the collar slid over it. Works like a charm now and snaps hard. Almost took out my camper when I first tried it . Thanks everyone for the help.