Pto not working right

[Rouany]

I’m trying to figure out what’s wrong with my pto it’s a John Deere 4105 and pto will engage and disengage as is supposed to but doesn’t have enough power to turn a brush hog and if I hook it up to a auger it spins it but as soon as I put pressure down it will stop moving

 

[Wagtail]

G'day Mate and welcome to TBN from Downunder.

What revs are you setting for using your 'bush hog'?

What size/make is the 'bush hog'?

Is this a recent occurrence?

Enjoy the site from wherever in the world you are.

 

[Rouany]

Like 2000 rpm it was working fine but doing some heavy brushing then stop for a drink and it just didn’t want to come back on but idont think the brush hog is the issue because it will not work with a auger I mean It will spin the auger but will stop moving as soon as I put pressure down on it also I can stop the pto with a 2x4

 

[Rouany]

I’m thinking if I don’t have the right pressure to and thru the valve then the clutch pack may be burnt but how do I check pressure and what kind of pressure should I have

 

[Wagtail]

Like 2000 rpm it was working fine but doing some heavy brushing then stop for a drink and it just didn’t want to come back on but idont think the brush hog is the issue because it will not work with a auger I mean It will spin the auger but will stop moving as soon as I put pressure down on it also I can stop the pto with a 2x4

First, if we (TBN) are going to be able to help you, we're going to need a wee bit of background information.

Have you owned your 4105 new or was it bought used? If 'used', do you have an Owner Manual? How many hours are on the tractor and, if over 400 hrs, did you drain & replace the hydraulic fluid?

What level is the hydraulic fluid? Ie: do you need to, at least, top it up?

2000 revs is OK for general, non-specific PTO implement, 4105 operations. The engine has a 'sweet spot': my 4105 likes it at 2100 rpm and can run 'all day' at that. 2500 rpm if I'm in 2x4 and on bitumen.

Your revs gauge shows, in yellow = 2800 revs, the revolutions required to ideally operate certain PTO implements such as a 'bush hog'/slasher or tiller. Each of those (or similar) implements have their own Owner Manual and maintenance schedules.

How big is the 'bush hog' that you're operating?

 

[RalphVa]

I had to run my 4010 @ PTO speed, which is about 3,000 rpm on it and probably the same for the 4105.

 

[ptsg]

A good working PTO will work from idle all the way to working RPM without slipping. Obviously the work it will do is a lot different between idle and 540. Heck, when I'm tilling the orchard, sometimes I just let the tractor go at idle while I'm busy fighting all the branches and moving them out of the way.

If it is slipping, something ain't right with the PTO clutch pack. The service manual should have the procedure to check the clamping pressure of the clutch pack and the values it should have. There is also the possibility of a stuck solenoid valve that isn't opening all the way, since this was kind of a sudden occurrence and not a long term issue that has gotten gradually worse.

 

[Tx Jim]

Ditto one needs to check hyd pressure on pto clutch.

 

[Rouany]

How do yo check pressure? Just put a gauge on the valve outlet or does it have a plug somewhere? What’s the specs I bought this tractor used but it was working

 

[ptsg]

Depending on the design, there could be various plugs on the PTO valve body that will check different things.

I think you really need a service manual to figure this out, otherwise it's like a shot in the dark. On the manual they tell you the correct port to check and what pressure it should be.