slip clutch modification

[kyoders]

In attempting to get my PTO slip-clutch properly adjusted, I've found the biggest problem is getting access to both ends of the spring-loaded bolts for adjusting the clutch pressure. The clutch I have is pretty much like all of the ones I've seen on the net, with two outer "covers" sandwiching in the clutch plates, with 4 pairs of bolts around the circumference to hold the two sides together. The nuts on the bolts have a large spring on them to keep pressure on the clutch disks. These are arranged such that the bolt head is toward the implement (and covered by the large bell of the PTO shield), and the spring/nut is toward to tractor. There is an access cover in the top of the shield bell that allows access to one pair of bolt heads at a time. Adjusting all 8 bolts requires lining things up such that one pair of bolts is accessible through the cover, then putting a socket with extension on the nut end and turning the desired amount. Then rotating to the next set, rinse repeat, etc. Without taking the PTO shaft off the tractor, this means "jogging" the PTO until the next pair of bolts is accessible, which of course they never come around the way you want them to.

What I'm wondering is, would it cause any problems if I took the bolt-end of the outer clutch cover and welded a small piece of steel alongside where the bolt head would be? The idea is to keep the bolt head from turning, eliminating the need to have a wrench on that end. I originally thought of trying a lock washer, but thought that might introduce too much variation in the pressure, and also require a longer bolt. My next thought was to weld the bolt head to the outer plate, but then I realized a small stop next to the bolt would be enough.

Can anybody think of a reason not to do this? I can't, but I also can't understand why the manufacturer's haven't done this already. It seems pretty obvious that this would make adjusting the clutch a lot easier. The only time you would need to get at the back side of the clutch through the access panel is to remove the whole thing from the implement.

Kevin

 

[JohnMiller3]

<font color=blue>...My next thought was to weld the bolt head to the outer plate...Can anybody think of a reason not to do this?...</font color=blue>

It will take you about 1 minute to unbolt and slide the whole slip clutch assembly off the implement gearbox input shaft...

then using 2 wrenches and by staggering your adjustments (like tightening down a head on an engine...) you can properly complete the task of adjusting the slip clutch torque "slippage"...

By leaving the slip clutch assembly on, and trying to "fight" working in the small access space (within the slip clutch plastic shield), it will take much longer...

 

[kyoders]

John,

The implement end of the clutch has a bolt on either side of the splined sleeve to lock it into the groove on the gearbox shaft. Getting at these bolts is much more difficult than getting to the clutch cover plate bolts. If you turn the shaft to where you can get to the bolt head, the nut is at the bottom of the shield bell, which you can't get at from behind because the clutch fits inside the bell with only about 1/4 to 1/2 inch clearance around it.

I found a different (but very similar) clutch at TSC that had a spring-loaded quick release to attach to the gearbox shaft. The problem is, it had a male splined shaft to attach to the driveline itself, where the current one has the yoke built into the clutch. By the time I adapted everything, the extra length added would make the driveline so short that it would be dangerous to use, if it were even possible. The clearance to the PTO shaft on the BX is pretty tight. Each half of the driveline is currently only 12 inches. The manufacturer (Eurocardan) recommends that you have no less than 1/3 of the length of each shaft overlapping. I've checked full-range motion with the 3ph, and at worst it leaves about 5 inches overlapping. If I had to cut another inch off of the halves, it would put me under 4".

Kevin

 

[Anonymous Poster]

Kevin...

I didn't realize you had a BX2000... you may not have enough adjustment range on the slip clutch springs before the nuts come off.../w3tcompact/icons/blush.gif (in other words, I believe the lowest torque range will still be way beyond the BX2200 capacity, not slipping when you expect it to...)

You can buy 8- “5mm” springs (just about all sc have 6mm) to lower the torque slippage but by the time you get done (expense wise and time)... you may be better off using a grade 2 shear bolt arrangement...

You should have "plastic" access covers on opposite sides of the slip clutch plastic guard assembly... most cases you would install this guard assembly with the access on the sides versus top/bottom arrangement...