Bush hog blade stopping

[CobyRupert]

Can you see the pto shaft (on the tractor side of any shear bolt) slow down when the blades slow down? This means the pto is probably slipping inside the tractor.

If the tractor’s pto shaft rpm stays consistent with the tractor engine’s rpm but the blades slow down, the slippage is elsewhere on the mower. Some shear bolts can be broke and look okay if the sheared head doesn’t fly out.

Like roadworthy says, check adjustment of pto clutch.

 

[LD1]

Can you see the pto shaft (on the tractor side of any shear bolt) slow down when the blades slow down? This means the pto is probably slipping inside the tractor.

^^^THIS

Basic troubleshooting.

The engine (indirectly through clutches and gears) drive the blades on the mower.

The only parts visible are
1. RPM's via the tach
2. The PTO shaft
3. The blades on the mower

Since 1. RPM's are not slowing, but 3. The blades are.....then you obviously have something slipping in between.

But what about #2. What is the PTO shaft doing? That alone will tell you if the issue is something on the tractor side, or on the mower side.

 

[Thomas]

Have you try mowing when grass good and dry?...it will give easy and better looking cut.

 

[yanmars]

The grass was dry. The tractor RPMs do not drop but the blade and the PTO shaft both slow and nearly stop. The New Holland does not have a foot clutch on the hydro trans. Will try to check more in the future. Thanks

 

[MESSMAKER]

Check your hydro fluid.

 

[yanmars]

I will but I am pretty sure I had it full a week or so ago.

 

[airbiscuit]

I've had shear pins break, with ends remaining intact giving the appearance that all is well. You've checked that, so the problem sounds like issues with the PTO clutch.

 

[LD1]

The grass was dry. The tractor RPMs do not drop but the blade and the PTO shaft both slow and nearly stop. The New Holland does not have a foot clutch on the hydro trans. Will try to check more in the future. Thanks

That's not good news. If the pto is slowing and the tractor is not....the clutch that drives the pto (inside the transmission/rear axle of the tractor) is slipping pretty bad.

 

[LD1]

How many hours and what's the age of this machine that a light duty kk 5' mower is slipping the internal clutch of a 40hp machine?

 

[yanmars]

The tractor has about 1850 hours on it, I would guess it is 20 years old or so. Never heavily used by me (us) but lent out and the guy abused it badly but i did not think he did any PTO work but bent the bucket and did other damage that was repaired.