Deere 855 Hydrostat pedal problem

[dminer]

My 755 has been giving me issues over the last year or so where the forward & reverse pedals would not go back to neutral a lot of the times.

I pumped the various grease fittings that are related to the hydrostat system and it helped a little but it still wasn't right. I crawled under the machine to see if anything was binding and what I found was a couple rollers that ride on a wedge next to the pump/motor were seized. I applied some grease to the wedge and things were better for a bit until the grease was rubbed off. I'll have to get some replacement rollers next year when I pull it out of storage.

I would suggest crawling under the tractor and examine the linkages and make sure there isn't any grease fittings you've missed and get an understanding of how everything works. It might be something fairly simple that need a little attention.

Jason

Jason,

My 755 exhibits the same tendency from time to time. My tractor has the mower deck on and it tough to get a look at anything under the tractor, especially anything inside the frame rails. Which side of the tractor are the wedges on, and are they inside the frame rails?

Thanks
Dale

 

[techwrtr2]

I had one 955 that the parking brake lever would not fully release when I stepped on the brake pedal. I would have to reach down and press down on the lever while stepping on the brake to get it to get it to fully release. On the 955 I have now, it fully disengages with a simple press on the brake pedal.

I experimented to day when I brought in some heat. Things seemed bound up at pretty much every point I released the brake so I pushed down on the knob for brake, it really didn't seem to move much but something definitely happened as each time the travel pedals engaged easily. This gives me something to look at when I find time to take the panels off for other repairs and maintenance.

 

[WinterDeere]

Well, I was under there today, doing the first full greasing of the tractor and FEL, since I bought the rig last month. All of the fittings showed fresh grease on them when I bought the machine, so I was in no rush, but since I already had the tractor in the garage to change some drippy hydraulic quick-disconnects, I went over all the grease points. I actually found a half dozen zerks that were completely clogged with rust or dried grease, and not accepting any grease when I pumped on them. I got all but one cleaned and flowing well, the troublesome one being where the steering cylinder connects to the right steering knuckle.

In any case, after a little playing around, the trouble with my pedals sticking does seem to be related to the parking brake lever. I found this lever is pulled down by a spring (not sure mine's right... will check the manuals), and this spring is too long to properly pull the handle all the way down. Manually pushing it down, as BigEddy described, seems to do the trick.

 

[Mechanos]

The tractor I had with the sticky lever was the first one I had. I just got used to reaching down and giving it a push to release the mechanism. It wasn't until I got the "new" one running that I realized how nice it was to just step on the brake pedal and go without having to reach down each time.

 

[WinterDeere]

Yeah... for me it's more about the fact that I might not be the only one using this machine. I don't want my wife or my father to have to remember to do that, or bump into something with the machine, when they have to press the pedal real hard to get it to move. I think the fix is as simple as replacing (or better arranging) the spring that pulls down on that lever.

 

[techwrtr2]

Yeah... for me it's more about the fact that I might not be the only one using this machine. I don't want my wife or my father to have to remember to do that, or bump into something with the machine, when they have to press the pedal real hard to get it to move. I think the fix is as simple as replacing (or better arranging) the spring that pulls down on that lever.

Your reasons to want to fix it properly are my own. There are other people who might want to utilize the machine and I don't want to have to spend a half hour every time they choose to use it explaining every odd quirk.

 

[bob arnold]

When my tractor sits and idles for a few minutes, such as when I climb off to close the overhead door after pulling it out of the garage, I find the pedals (both forward and reverse) sometimes seem to be stuck. Not mechanically stuck, but more like there's hydraulic back pressure on them, preventing me from pressing them to more than crawl speed.

If I tap either one of them hard, the tractor of course lurches a bit, but then they go back to feeling normal, and I can drive the machine normally after that. I'll obviously check the seat "operator presence" linkage, but like I said, I think this is a hydraulic problem. Anyone ever heard of this?

How did you come out on this? Was it the linkage to the seat or some other problem.

 

[WinterDeere]

It was the parking brake linkage. The spring designed to unload the parking brake when released (located near the park brake handle, under tractor) was so worn out that it would not fully pull this handle down. I never traced it to be sure, but I assume there's some pedal lock-out linkage connected to this. The fix was to be sure the parking brake lever is always pushed all the way down (released), before pressing the fwd/rev pedals. I had planned to replace this spring, but actually forgot!

 

[bob arnold]

It was the parking brake linkage. The spring designed to unload the parking brake when released (located near the park brake handle, under tractor) was so worn out that it would not fully pull this handle down. I never traced it to be sure, but I assume there's some pedal lock-out linkage connected to this. The fix was to be sure the parking brake lever is always pushed all the way down (released), before pressing the fwd/rev pedals. I had planned to replace this spring, but actually forgot!

I was hoping it was the seat linkage. My problem is that just pushing on the brake pedal to come to a stop causes the hydro pedals to stick. I think my problem may have to do with hydraulic pressure. In addition, the situation seems worse during colder temps, which also makes me think its hydraulic related.

Thanks for you reply

 

[techwrtr2]

It was the parking brake linkage. The spring designed to unload the parking brake when released (located near the park brake handle, under tractor) was so worn out that it would not fully pull this handle down. I never traced it to be sure, but I assume there's some pedal lock-out linkage connected to this. The fix was to be sure the parking brake lever is always pushed all the way down (released), before pressing the fwd/rev pedals. I had planned to replace this spring, but actually forgot!

You're doing basically as I've been for the last year. I usually will just push the lever down by hand when releasing the brake. One of these days I need to take the tin off my tractor and do some much needed work on it to repair a variety of needs. I just use it so much that I don't want to be without not to mention I only have weekends where the tractor lives to do any work.

Maybe if I got some lights on the Beaver again I could clear snow and do the other stuff I use my 855 for during the winter so that said 855 can get the treatment it deserves.