Bush hog blade stopping

[TMGT]

The tc40 uses a hydraulic actuated pto clutch pack, sounds like either the clutch is worn or more likely the pressure to it low (which will cause the clutch pack to wear prematurely).

You need to check the clutch hyd. pressure, if that is within spec you'll most likely be pulling the clutch pack out.

 

[workinonit]

Based on your description it definitely seems you have internal issues. If you don't think so, drop that bush hog off and put something else PTO driven on to see if the tractor responds the same way. I would be very, very surprised if you have something wrong with that bush hog. I think your issues are much more serious. Get to troubleshooting. And good luck.

 

[CobyRupert]

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

This was OP’s post (#14).
Seven pages later and we’re still wondering where the problem is?

If the tractor’s PTO shaft nearly stops but the tractor engine’s rpms do not drop, it’s an tractor PTO problem.

 

[ruffdog]

It has a new hydraulic filter and fluid about 5 hours ago.

Hmmm. Was the correct fluid used or the cheap yellow pail stuff? The wrong fluid may cause clutch slippage.

I would be careful with fluid type with a wet clutch.

 

[CobyRupert]

Does the PTO shaft look like this where it connects to tractor?
If the bolt is sheared, the mower’s PTO shaft will slow down, but you may think it’s the tractor’s PTO shaft that slowed down when it really hasn’t.

 

[Midniteoyl]

It has a new hydraulic filter and fluid about 5 hours ago.

I would head right back to this point and make sure nothing bad happened here, like a bad and/or blocked filter, blocked/damaged screens, blocked passages, wrong fluid (?), etc.

 

[Midniteoyl]

They do indeed intentionally de-tune machines to hit a target HP point.

By and large, I think most of it comes from less informed customers, and competition.

Take my brand of choice for example. Current models I think are the MX5400 and MX6000.

Lets say someone is looking for a 50 HP tractor......and they are looking at a 4052r deere. Then they go into kubota and want to look at something similar. IF kubota only has the MX6000.....and the next step down is an L-series.....kubota might not get a sale.....because it only has a 60 HP tractor to offer. And the "less informed" customer is gonna look at that and say thats an unfair comparison....and he'd have to go back to deere and compare a 60HP machine which is more money. ANd its an ever ending upward spiral.

Regarding "more HP is never a bad thing".....well it depends. The nature of having two identical machines with one turned up a bit....is it drinks more fuel. Comparing the MX5400 and MX6000 tractors....if all one was doing was loader work....ground work like pulling a plow....grapple work doing firewood, etc......then why burn more fuel to get the extra 6 ponies that you aint gonna benefit from. Likewise if its predominately a mowing tractor or some other heavy PTO uses.....then sure you can benefit.

Sure it cost them the same to make. But they still make a profit. Lets say the MX6000 has a profit margin of 30%. IF thats the ONLY model then you make 30% on everyone sold. But if you can make the SAME tractor....cut profit to 20%.....but increase customers and sales its worth it.

All of this is nothing new and has been going on for better than half a century.

Wrong thread?

 

[yanmars]

All fluids, filters etc. were changed just last year. Not many hours ago. Fluid supplied by the New Holland dealer for the tractor. The shear pin is not broken, I took it out to check. The nut holding the bush hog blades on still has the retaining cotter key intact.

 

[airbiscuit]

So what are your plans fore a fix?

 

[TMGT]

Have you checked the PTO clutch pressure yet?

All fluids, filters etc. were changed just last year. Not many hours ago. Fluid supplied by the New Holland dealer for the tractor. The shear pin is not broken, I took it out to check. The nut holding the bush hog blades on still has the retaining cotter key intact.

 

[LD1]

Wrong thread?

whoops

 

[DieselBound]

I'm in agreement with others who suggest this being a hydraulic issue. I'd take a close look at the various filters for the hydraulic system. The HST might be taking up as much of the hydraulic flow as possible and leaving insufficient flow to drive the PTO. With low-load there's enough flow for the PTO to handle the lighter grass.

Not sure how possible it is, but perhaps try putting your tractor into your higher grass and run the RC while NOT in gear/traveling. This would assure that all available hydraulic flow is available for the PTO. I'm no expert in any way on hydraulics, but I'm thinking that IF the cutter is able to cut w/o any issues that it wouldn't be a PTO clutch-pack but a basic system flow issue (filter would be an issue perhaps- I know that there are things like strainers- my B7800 has one and it's maintenance schedule calls it out to be cleaned).

Please note that "filters and fluid changed [recently]" isn't qualifying things. No idea if the prescribed procedures were done PROPERLY. Again, note my comment above on the strainer. If someone doesn't know about something like this then it's something that is likely going to be missed (until one finds one has a problem).

 

[ptsg]

I'm in agreement with others who suggest this being a hydraulic issue. I'd take a close look at the various filters for the hydraulic system. The HST might be taking up as much of the hydraulic flow as possible and leaving insufficient flow to drive the PTO. With low-load there's enough flow for the PTO to handle the lighter grass.

Not sure how possible it is, but perhaps try putting your tractor into your higher grass and run the RC while NOT in gear/traveling. This would assure that all available hydraulic flow is available for the PTO. I'm no expert in any way on hydraulics, but I'm thinking that IF the cutter is able to cut w/o any issues that it wouldn't be a PTO clutch-pack but a basic system flow issue (filter would be an issue perhaps- I know that there are things like strainers- my B7800 has one and it's maintenance schedule calls it out to be cleaned).

The HST is a separate hydraulic pump and motor combo. The only thing it shares with the rest of the hydraulics on the tractor is the fluid.

There is, however, two hydraulic gear pumps. One, the smaller one, handles the steering and the PTO clutch pack (lube and pressure). The second and bigger pump runs everything else on the tractor like, loader, 3pt and remotes.

To the OP, at this point, just grab the workshop manual for that tractor, get a pressure gauge and figure where to check the clutch pack pressures using the manual as guide. Then proceed from that.

 

[yanmars]

Did not check the pressure. Have no gauges at this time to do so. Will check the NH manual to see if there is a screen. Since my main tractor is down and I need to get areas mowed before grass waterway work can be started I mowed at follows. Tractor RPMs as should be, very slow forward speed. Mowed first 18 inches high, then 12 and then 6 or so. Got the mowing about done but it was very slow. Took about 4 times longer than normal but as least I was able to get it done almost. Did not bog down much so overall it worked.
I do not want to bring it to the shop at this time or I am without a mower.

 

[workinonit]

This was OP’s post (#14).
Seven pages later and we’re still wondering where the problem is?

If the tractor’s PTO shaft nearly stops but the tractor engine’s rpms do not drop, it’s an tractor PTO problem.

No, we're not all wondering. Not but one thing it can be.

 

[TMGT]

Did not check the pressure. Have no gauges at this time to do so. Will check the NH manual to see if there is a screen. Since my main tractor is down and I need to get areas mowed before grass waterway work can be started I mowed at follows. Tractor RPMs as should be, very slow forward speed. Mowed first 18 inches high, then 12 and then 6 or so. Got the mowing about done but it was very slow. Took about 4 times longer than normal but as least I was able to get it done almost. Did not bog down much so overall it worked.
I do not want to bring it to the shop at this time or I am without a mower.

Check the pressure asap, if the clutch pack isn't fried yet it will be in short order if you keep using it. Not familiar with the NH but other brands use a relatively low pressure for the clutch pack, usually around 4-500psi. Gauges and adaptors are cheap, the clutch pack and time to replace are not!
Hopefully its just low pressure and you can catch it in time and save it.

 

[yanmars]

I have parked it for now.

 

[airbiscuit]

Right answer.

 

[Tx Jim]

I have parked it for now.

If it was my tractor I'd block clutch pedal down when sitting idle for any lengthy period of time

 

[yanmars]

Just an update. I am thinking it is a PTO issue. When the PTO was turned off the noise ended. Also with the PTO off the tractor functions and operates normally with full power.

If it is a PTO seal etc. issue is that an expensive fix? For what I need to do now, loader work etc. I do not need the PTO.
Can use my other tractors for that but just curious if any idea about such repair costs for anyone having had that done. Thanks