John Deere 870 engine/ transmission sound

[Freedom.acres]

This is a 1992 John Deere 870 with about 1300 hours. It is making a humming/ whining sound that seems to originate from the distribution box located at base of steering column. When the whining starts the motor rpm’s also increase any insight would be great.

 

[bmaverick]

This is a 1992 John Deere 870 with about 1300 hours. It is making a humming/ whining sound that seems to originate from the distribution box located at base of steering column. When the whining starts the motor rpm’s also increase any insight would be great.

You have basically a Yanmar kit tractor assembled at a Deere facility. Its a Yanmar FX24D in red paint and different hood otherwise. Both are really nice machines.

A few things to check.
- Fuel bowl for cracks or leaks.
- Fuel bowl o-ring gone bad.
- Fuel injector pump issues, even with the governor rod.
- Clutch plate noise issues can resonate to that area.
- Starter/flywheel issues in the area.
- Hydraulic suction pipe with the 6-inch jumper hose could have a leak.
( I just fixed mine, so I know about this noise down there too.)

Is there a decompression linkage or cable on this 3TN84 engine? I know the 3T80 and 3T84 had them.
If the lock nut moved, a slight open air to the 3 cylinders would be had. A little less power and more engine RPMs.

Its great the machine has a 3T84 family engine. Yanmar put it in nearly EVERYTHING. So parts globally can be found easily and at good low Yanmar parts network prices. No green paint insane markups.

I might have the Service Manual some place or know where to grab the PDF. It will help you on the hunt to solving the issue.

 

[Freedom.acres]

You have basically a Yanmar kit tractor assembled at a Deere facility. Its a Yanmar FX24D in red paint and different hood otherwise. Both are really nice machines.

A few things to check.
- Fuel bowl for cracks or leaks.
- Fuel bowl o-ring gone bad.
- Fuel injector pump issues, even with the governor rod.
- Clutch plate noise issues can resonate to that area.
- Starter/flywheel issues in the area.
- Hydraulic suction pipe with the 6-inch jumper hose could have a leak.
( I just fixed mine, so I know about this noise down there too.)

Is there a decompression linkage or cable on this 3TN84 engine? I know the 3T80 and 3T84 had them.
If the lock nut moved, a slight open air to the 3 cylinders would be had. A little less power and more engine RPMs.

Its great the machine has a 3T84 family engine. Yanmar put it in nearly EVERYTHING. So parts globally can be found easily and at good low Yanmar parts network prices. No green paint insane markups.

I might have the Service Manual some place or know where to grab the PDF. It will help you on the hunt to solving the issue.

Any chance I could email you a quick video with some audio to listen to the sound.

 

[bmaverick]

Any chance I could email you a quick video with some audio to listen to the sound.

You could post it on YT or other site and the link here. I'm at work having no ability for outside content to play. Email and forums is all I can do really. I can listen to it tonight.

 

[Freedom.acres]

You could post it on YT or other site and the link here. I'm at work having no ability for outside content to play. Email and forums is all I can do really. I can listen to it tonight.

Thanks

 

[bmaverick]

Any chance I could email you a quick video with some audio to listen to the sound.

Does this 870 have OE power steering? The hum/whine on my phone sounds like a bearing going bad.

STEERING SHAFT BEARING

There are cam shaft bearings and bearings at the flywheel.

 

[Freedom.acres]

Does this 870 have OE power steering? The hum/whine on my phone sounds like a bearing going bad.

STEERING SHAFT BEARING

There are cam shaft bearings and bearings at the flywheel.

The tractor is fairly new to me and although fairly mechanically inclined I’m pretty new to working on tractors what would I look for to find out if it has power steering because I’m pretty sure this model was made both with and without. Thanks

 

[loggin]

The tractor is fairly new to me and although fairly mechanically inclined I’m pretty new to working on tractors what would I look for to find out if it has power steering because I’m pretty sure this model was made both with and without. Thanks

I believe your tractor is geared, does have a 2 stage clutch? Does the noise go away after depressing the clutch in either stage? Just trying to eliminate certain areas.

 

[Freedom.acres]

Does this 870 have OE power steering? The hum/whine on my phone sounds like a bearing going bad.

STEERING SHAFT BEARING

There are cam shaft bearings and bearings at the flywheel.

I believe your tractor is geared, does have a 2 stage clutch? Does the noise go away after depressing the clutch in either stage? Just trying to eliminate certain areas.

Geared yes 2 stage clutch yes noise is intermittent but does not go away when depressing clutch. I’m fairly confident the sound is coming from distribution box at base of steering column

 

[bmaverick]

The tractor is fairly new to me and although fairly mechanically inclined I’m pretty new to working on tractors what would I look for to find out if it has power steering because I’m pretty sure this model was made both with and without. Thanks

When seated on the tractor, to the left side a hydraulic cylinder to the front axle pitman arm would be there for power steering.

Listening to the noise in the YT vid, it's constant and does wind up and down with RPMs. I would assume it's a bearing.