G clutch again....

[coonie minnie]

So, a month or so ago I got the clutch back together on my G. New facings, toggles, dogs, bolts. Yet I still have a problem... if I set it up nice and tight, like it should be, it won't stop. If I loosen it so it won't drag, it will slip very easily.

What am I missing????

The bearing seemed good, I repacked it with grease so I don't think that is dragging.

I've replaced the pulley brake, and messed with the adjustment.

The drive disk is on correctly, and about flush with the end of the crank.

I THINK the brass fork is in the right place.

I and T suggests milling some off the operating sleeve in such situations.... is this something I need to consider?

The tractor had similar symptoms prior to coming apart. I did find a crack in the center disk, and a cracked dog... I hoped this would solve the issue. Ideas out there??????

 

[coonie minnie]

I would add that I was a bit concerned with the new dogs... they were from an aftermarket supplier, and the holes were not drilled particularly straight.

 

[RLA]

Well from my experience if the drive disk to flush with the crank shaft it's going on too far. You could reinstall a worn inside clutch
disk & see if that helps I believe your issue is it's dragging on the inside facing. Or you could attempt to make a brass shim for the driver
as a test. I've used a pop can too. If you can get it to fit & if you get it tight it will last a VERY LONG time. It's cheaper than buying a
driver. This is my 2 cents.. LOL

 

[Mark-Ia]

Is your clutch brake adjusted correctly?

 

[Broken wheel]

If you used an after market pully brake pad, they are too thick. I had the same problem on a J D 70. If there is too much wear on the sleeve the clutch will start to engage when you pull the clutch lever back. You can check that by pulling back on the lever when the pully is stopped and see if it starts to drive again.

 

[coonie minnie]

Thanks for the advice, gentlemen...

 

[Ken in MN]

I recently did a clutch on a late G and had somewhat similar issues. In my case, the aftermarket disc/facing that slides onto the bolts was binding on the bolts. I drilled the holes out just enough for them to slide freely on the bolts.

 

[coonie minnie]

I'll look at that, too.

 

[coonie minnie]

I was wondering about this as well. Thanks

 

[RLA]

Only other thing might be give it a little more crank shaft endplay.

 

[coonie minnie]

End play is pretty tight right now...

 

[kurt v]

Do you have the discs on the correct pins (rod) ?

 

[RLA]

I had a issue with a 620 black dash, but I had too much clearance in the inside disk, I figured that out after I replaced everything new & still had a problem. New dogs, pin's, adjusting T bolts, brass fork floating plate all the disk. Only thing that wasn't new was a adjusting plate, drive disc & pully. Drive disk fit perfect & lacked a little better than a 1/8 from flush with the crank. When tractor was shut down & clutch adjusted seemed perfect, but when running wide open it would fall out. Loosen the adjustment it would not fall out/ disengage but it would slip. What what happening only pulling on the outside of the disk. I tired moving the crank shaft but was already against the the plastic spacers inside the case. If I install 2 worn disc on the inside it worked perfect. I removed the pulley from our 630 which worked perfect & installed on ton the 620. The clutch worked perfect, with little effort to snap in & it wouldn't slip. So I put the whole pulley on the 630 & it suddenly had the same problem. What I found out in the end the pulley on the 620 was cut too deep. When I bought the tractor the man told me, ever since he owned it, they clutch was hard to get it right & keep adjusted right. I thought I could fix that easy? Once I found a good used pull asy, the tractor now has a nice clutch. There was almost 3/16 difference between the 630 pully & the 620 pulley measuring from where the cover mount to the machined clutch face.. The used pull I bought came off a 630 also, it was a struggle but it's fixed.

 

[coonie minnie]

I'm not completely clear on where you are measuring from???

 

[coonie minnie]

On a G, they go on the bolts... there are no pins like on a 70 or similar...

 

[RLA]

Outside edge of where
clutch cover clips on, also measured down through the bearing to the drive gear , that distance was shorter too but can't recall how much. Both drive rears on either clutch appeared to be pressed on the same. Where the pulley was machined for the inside disc with naked eye you could see the difference . What I needed on the inside disc that was a clutch disc near 3/8 thick or maybe more. I ran it for awhile with 2 worn disc, much thicker than one on the inside position, but I wasn't sure how long it would last? Plus thought about one breaking in 1/2 & causing engagement when I didn't want it. So I J/B Welded two disc together. It worked fine for a few months , but I bought a used Pulley in the end & fixed it right. Paid big money for it too... I thought about filling the drive disc so it would go on father, but it fit perfect so I didn't. That part was correct, it was the pulley assy that wrong. Took the pulley to a machine shop & asked about spray welding or adding 3/16 to it, I didn't know if it would hold up & they though the same. Looking at one pulley I would have never found the problem as looking at a Known Good pulley it became obvious. Having a 630 with the same parts was the key to my success.

 

[620 John]

(quoted from post at 11:44:12 05/08/21) Outside edge of where
clutch cover clips on, also measured down through the bearing to the drive gear , that distance was shorter too but can't recall how much. Both drive rears on either clutch appeared to be pressed on the same. Where the pulley was machined for the inside disc with naked eye you could see the difference . What I needed on the inside disc that was a clutch disc near 3/8 thick or maybe more. I ran it for awhile with 2 worn disc, much thicker than one on the inside position, but I wasn't sure how long it would last? Plus thought about one breaking in 1/2 & causing engagement when I didn't want it. So I J/B Welded two disc together. It worked fine for a few months , but I bought a used Pulley in the end & fixed it right. Paid big money for it too... I thought about filling the drive disc so it would go on father, but it fit perfect so I didn't. That part was correct, it was the pulley assy that wrong. Took the pulley to a machine shop & asked about spray welding or adding 3/16 to it, I didn't know if it would hold up & they though the same. Looking at one pulley I would have never found the problem as looking at a Known Good pulley it became obvious. Having a 630 with the same parts was the key to my success.

This is pretty interesting because i know someone with a 620 that has an issue like described. I know the clutch driver on this one is about flush with the crank but from what you're describing that might not be the only cause. Thanks for the info. I'll keep it in mind next time I can look at it.

 

[PJH]

RLA - Thanks for the detailed description on your 620 clutch. I'm having similar puzzling issues with my 620 clutch. I also have a 630 with a perfectly operating, easy to adjust and trouble free clutch. I'm gonna do some measuring.

 

[RLA]

It must be a late model 620, Black dash for it to have the same parts as a 630. my serial # 6221964 J/D made CHANGES & made it a better clutch in the end.