2018 John Deere 6135 problem

[DocMorrow]

Hello all.
I am a computer engineer and live nextdoor to a farm. I was asked to have a quick look at a problem the farmer is having with his tractor - a John Deere 6135. Although I doubt it has any electrical problems that I could be of any use in solving, he did ask my opinion on an issue it is having. It has an odd knocking (kind of bubbling) sound coming from the front side of the cab on the clutch side when going downhill - and only downhill. I suspect it to be a hydraulic issue somewhere on the cab suspension but the farmer thinks it could be the coupling between the engine and gearbox. I was wondering if anyone else has had a similar experience and if its something that needs an immediate fix before it becomes a major problem. As we all live out in the back of beyond, its a bit of a task (and expensive) to get someone to come out and look at it though he has had a local engineer take a look and he can't seem to find anything wrong. Having been out with him in the tractor, it is quite a disturbing sound and its not easy to place exactly where the sound is coming from.
Any suggestions are welcome. Thanks in advance.

 

[Tractortech]

Hello all.
I am a computer engineer and live nextdoor to a farm. I was asked to have a quick look at a problem the farmer is having with his tractor - a John Deere 6135. Although I doubt it has any electrical problems that I could be of any use in solving, he did ask my opinion on an issue it is having. It has an odd knocking (kind of bubbling) sound coming from the front side of the cab on the clutch side when going downhill - and only downhill. I suspect it to be a hydraulic issue somewhere on the cab suspension but the farmer thinks it could be the coupling between the engine and gearbox. I was wondering if anyone else has had a similar experience and if its something that needs an immediate fix before it becomes a major problem. As we all live out in the back of beyond, its a bit of a task (and expensive) to get someone to come out and look at it though he has had a local engineer take a look and he can't seem to find anything wrong. Having been out with him in the tractor, it is quite a disturbing sound and its not easy to place exactly where the sound is coming from.
Any suggestions are welcome. Thanks in advance.

Now Then..
How many hours has this tractor done?? What transmission does it have??
Are you sure about the tractor model number??

 

[DocMorrow]

He's not around at the moment, but I will check. His wife may be in, I'll wander over and take a look.

 

[DocMorrow]

Right. It is a 6135 and its the basic model "R", It's done around 4000 hours. It has a what amounts to an automatic, or semi automatic, gearbox. There isn't a clutch as such, not really familiar with it's gearing system but I gather that there is some kind of bush system that connects the motor to the gearbox - which is what he suspects may be the problem. There is also a pump that returns the hydraulic fluid back to the reservoir which has some kind of additive, I think, to stop the pipes from clogging which could be to blame.
Sorry, I am not that familiar with newer tractor's and the farmer isn't that familiar with the internet.

 

[acorn]

Just check that the draw bar pin (or anything else) isn't rolling round in the toolbox.......!.

 

[Tractortech]

Here's a link to JDParts, it should be the right catalogue, I'm sure you'll be able to navigate to the right one if not... It's only a model year thing..

https://partscatalog.deere.com/jdrc/navigation/equipment/4827

You can familiarise yourself with the drivetrain set up if you like.. Also, look up the operators manual here,,,,

John Deere - Technical Information Store - Technical Information Store

Official John Deere site to buy or download Ag & Turf operator’s manuals, parts catalogs, and technical manuals to service equipment. The site also offers free downloads of operator’s manuals and installation instructions and to purchase educational curriculum.

techpubs.deere.com

There are 3 transmission options as I recall. All 3 will have a damper bolted to the flywheel on the engine, a short universal jointed shaft connects this to the transmission. The pump within the transmission provides pressure for the transmission, the lower part of which is the 'reservoir'. The Powrquad transmission has an air pump to push oil from the Powrquad unit back to the main transmission. It's best to not refer to the oil as hydraulic fluid. It's transmission oil, Hygard from John Deere (other fluids exist obviously). It contains anti foaming and anti skwalk additives, hydraulic oil doesn't (though it may have anti foaming)..
Does the tractor have the right oil in and tobthe correct level??

 

[DocMorrow]

We have found the problem.
An engineer came to take a quick look. He found a piece of casting floating around in the bottom of the sump that seemed to be causing the crankshaft to shift when the tractor was at a certain angle. Surprisingly, it doesn't seem to have caused any major damage. He wasn't sure whether it was a part of one of the con rods or part of the engine casing, hopefully not part of the gearbox.
Anyway, I hope that this may come in useful for anyone else experiencing similar issues. I will see what the end result is and what the solution ends up being and post it up. Hopefully not as eye watering expensive to put right as I can imagine.

Thanks to you all for your insights.