Rotary Cutter Slip clutch not slipping at factory specs...

[Farmwithjunk]

Maybe the 285 is too much cutter for my tractor? I have no idea. All I know is that the tractor dies before the clutch will slip.

I'm using a 286 on my MF150, which has essentially the same engine/tranny/rear end/pto as your 231. I have ample power (with my Perkins AD3-152). Are you talking about simply bogging it down in heavy weeds, or are you referring to the clutch not slipping when you hit (solid) a "buried treasure". Sounds like your clutch may need to be set a little "softer".

 

[Travis_R]

I'm using a 286 on my MF150, which has essentially the same engine/tranny/rear end/pto as your 321. I have ample power (with my Perkins AD3-152). Are you talking about simply bogging it down in heavy weeds, or are you referring to the clutch not slipping when you hit (solid) a "buried treasure". Sounds like your clutch may need to be set a little "softer".

Clutch is not slipping when I hit something solid...

If I loosen the nuts on the slip clutch 1 more full turn, I'll probably be able to turn the clutch springs with my fingers... I'm 100% positive the clutch is not froze up. I completely loosened all the nuts on the clutch to where I could spin the springs by hand. I then turned the PTO driveline by hand and the gearbox didn't turn. This tells me that the clutch is NOT froze up.

 

[EE_Bota]

Clutch is not slipping when I hit something solid...

If I loosen the nuts on the slip clutch 1 more full turn, I'll probably be able to turn the clutch springs with my fingers... I'm 100% positive the clutch is not froze up. I completely loosened all the nuts on the clutch to where I could spin the springs by hand. I then turned the PTO driveline by hand and the gearbox didn't turn. This tells me that the clutch is NOT froze up.

Why is the ability to turn the springs with your bare hands a problem? Does that mean the nuts will come loose? I would not care if I could turn the springs by hand.

 

[Egon]

The nature of a slip clutch of the type we are talking about usually ends up as an empirical adjustment to suite the existing machinery and conditions.:thumbsup:

True, there are Factory given set points but these may basically be for liability protection with in field adjustments in mind.

 

[Travis_R]

The nature of a slip clutch of the type we are talking about usually ends up as an empirical adjustment to suite the existing machinery and conditions.:thumbsup:

True, there are Factory given set points but these may basically be for liability protection with in field adjustments in mind.

I agree and believe this to be true.

 

[IslandTractor]

Clutch is not slipping when I hit something solid...

If I loosen the nuts on the slip clutch 1 more full turn, I'll probably be able to turn the clutch springs with my fingers... I'm 100% positive the clutch is not froze up. I completely loosened all the nuts on the clutch to where I could spin the springs by hand. I then turned the PTO driveline by hand and the gearbox didn't turn. This tells me that the clutch is NOT froze up.

If you want to experiment then mark the bolt positions, tighten the spring bolts just enough so that the clutch doesn't slip when you start the PTO and rev the engine to typical mowing speed. If it doesn't move from the mark then go mow and see how it works. You don't want the bolts too loose but can check that by seeing a) if the blade is cutting and b) that after a few minutes of mowing in typical grass that the clutch is not warmer than the PTO shaft. If you really want to you could get one of those infrared thermometers ($29 at HF this week) and do before and after readings of the clutch and surrounding parts.

 

[Travis_R]

If you want to experiment then mark the bolt positions, tighten the spring bolts just enough so that the clutch doesn't slip when you start the PTO and rev the engine to typical mowing speed. If it doesn't move from the mark then go mow and see how it works. You don't want the bolts too loose but can check that by seeing a) if the blade is cutting and b) that after a few minutes of mowing in typical grass that the clutch is not warmer than the PTO shaft. If you really want to you could get one of those infrared thermometers ($29 at HF this week) and do before and after readings of the clutch and surrounding parts.

Great idea, but there's nothing to mow here right now. :laughing:

 

[JRobyn]

There's nothing too difficult involved ..... disassemble it, inspect and clean it up isn't so bad. I remove mine ... it gets stripped down, checked and stored inside for the winter. ..... set of dial vernier calipers

Rant over..

Sean

Sean, I totally agree with your point that routine clutch maintenance is not difficult, but IMHO you are making it a lot more difficult than it needs to be! Mine sits outside all winter (has the little sheetmetal cover over it), and then at first mowing, the nuts/springs get loosened to about where the springs can be turned by hand, then engage the PTO (I up the RPM to about 2000, clutch the tractor, engage the PTO and then rapidly engage the tractor clutch to put just a BIT of "shock" to the slip clutch). This almost always forces the slip clutch to slip - slippage is obvious for several reasons - first a puff of rusty dust from the clutch plate/disks, then a not-so-subtle raspy sound of the clutch slipping, plus, the cutter is NOT turning. Then a bit of cool-down is in order before re-tightening the springs/nuts. I use one of those simple rulers with the sliding bar. It lets me re-tighten all of the springs to within maybe 1/64 in or so. One year I did have to put the cutter down on some thick grass to get the rusted clutch plates to free up.

 

[SPYDERLK]

Great idea, but there's nothing to mow here right now. :laughing:

From your descriptions it sounds as tho something is wrong with the slip clutch. It is only free when the springs are all the way loose and locked up as soon as the springs start to compress. If that is a true interpretation the slight internal movement caused by spring tension must be bringing 2 parts into a mechanical interlock condition. The normal friction connection between the input/output sides, common in a correctly working clutch, should be a pretty smooth progression as springs are compressed. If the clutch is actually giving an abrupt ON/OFF there is something wrong internally. You should probably check it out more carefully before you have to. It seems the tractor PTO clutch, and elastic torsion in the drive are the only non destructive force limiters you have right now.
larry