[SennaMiller]

Just purchased an 855 compact tractor (year 1997). Had not been run very much for 4 years. Serviced fluids and used for a couple hours, forward and reverse petals were very stiff, but when you stopped pushing on them, the petal would come back to neutral and machine would come to a stop as it should. Seems like the spring or some other mechanism related to having the petals come back to neutral has broken, as now the petals will stay where you push them to (in forward or reverse) and have to lift up on the petal to get the machine to stop moving. I looked in the parts diagram and am having trouble figuring out what spring or mechanism is broken that is causing this behavior. I have several other parts that failed in my first hours, but have been able to figure all those out and order parts, but this forward/reverse issue has me stumped. Any help would be greatly appreciated. Senna

 

[Fedup]

I'm no authority on this series, but here's my take on your problem.

https://partscatalog.deere.com/jdrc/sidebyside/equipment/73152/referrer/navigation/pgId/14438610

It looks like the pedals are each connected to a rod (13) which then connects to cam (21). One pedal moves the cam forward, the other pedal moves it rearward. Whatever the centering spring mechanism is, would be involved with the movement of that cam. I would disconnect both of the rods first to see if the problem is mainly in the pedal movement. (stiff or rusty pivot bushings, etc) If the pedals are not the problem, then follow the cam to wherever it connects and look for something similar there.

 

[theduke]

Theres a few issues that pop up with these.

First...Figure out which 855 you have.
Early model is built off the 755....battery behind dash and fuel tank up front. 70 loader
Later model is more 955......Fuel tank behind dash and battery up front. 70A loader

The pedals have like 5 grease fittings on that same shaft as the master brake.
Grease all of them ..there are more inside the frame rails iirc.
Use wd or other spray oil and soak it all good after.

There is some cam system bunch of bs in between the 2 pedals somewhere.....been known to fail.

The Cruise control and parking brake linkages are ALL part of the system and tied to each other...its crazy.
Lastly.......follow the forward linkage.......press pedal and you will see it move just in front of rear axle.
Where that linkage bolts on is a 1" spacer...That bolt tends to loosen and sometimes break.
pita to get too but not horrible.

The manual has a huge chapter just for all this linkage.
Here is the manual..it covers 655-955.......its not perfect but this is all there is.

http://www.golftechs.us/Manuals/JDtractors.pdf

Verify Which 855 you own....likely the later one

 

[SennaMiller]

Theres a few issues that pop up with these.

First...Figure out which 855 you have.
Early model is built off the 755....battery behind dash and fuel tank up front. 70 loader
Later model is more 955......Fuel tank behind dash and battery up front. 70A loader

The pedals have like 5 grease fittings on that same shaft as the master brake.
Grease all of them ..there are more inside the frame rails iirc.
Use wd or other spray oil and soak it all good after.

There is some cam system bunch of bs in between the 2 pedals somewhere.....been known to fail.

The Cruise control and parking brake linkages are ALL part of the system and tied to each other...its crazy.
Lastly.......follow the forward linkage.......press pedal and you will see it move just in front of rear axle.
Where that linkage bolts on is a 1" spacer...That bolt tends to loosen and sometimes break.
pita to get too but not horrible.

The manual has a huge chapter just for all this linkage.
Here is the manual..it covers 655-955.......its not perfect but this is all there is.

http://www.golftechs.us/Manuals/JDtractors.pdf

Verify Which 855 you own....likely the later one

Thanks so much for all the information. The serial number indicates it is a 1997 year JD855, so it is a later built one. You are the second reply to mention the cam system. I will follow all the petal linkages and grease/lubricate and check for broken parts. I'll post to let you know what I find. I'm a farmer, so may take me a day or two to make time to do the diagnostics. I do have the full operators and technical manuals, so will check there to make sure I hit all the grease fittings in the forward/reverse system. Also, you mentioned that the cruise control and parking break are also in the same system...these are both very stiff as well, so thinking a thorough lube and WD-40 treatment may help, but I do think something broke, probably the cam system, as I did hear a clunk noise when the petal seemed to no longer want to return to neutral. Thanks for your help. Senna

 

[theduke]

Somewhere on the GTT forum is a fairly well detailed thread about this CAM part.
Theres some pretty good pics in there as well.

It may take a bit of searching but I bet googling your issue may take you to it.

Pretty sure it was a 955...but thats basicly what you have.......very slight difference in the 2.
rear axle is wider on 955
front wheels have 1 xtra lugnut on 955
and like 3 hp @ pto

and the sticker kit

 

[wesara4513]

I'm no authority on this series, but here's my take on your problem.

https://partscatalog.deere.com/jdrc/sidebyside/equipment/73152/referrer/navigation/pgId/14438610

It looks like the pedals are each connected to a rod (13) which then connects to cam (21). One pedal moves the cam forward, the other pedal moves it rearward. Whatever the centering spring mechanism is, would be involved with the movement of that cam. I would disconnect both of the rods first to see if the problem is mainly in the pedal movement. (stiff or rusty pivot bushings, etc) If the pedals are not the problem, then follow the cam to wherever it connects and look for something similar there.

y^^^^y


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