Deere 855 Hydrostat pedal problem

   / Deere 855 Hydrostat pedal problem #1  

WinterDeere

Elite Member
Joined
Sep 6, 2011
Messages
3,276
Location
Philadelphia
Tractor
John Deere 3033R; JD 855 MFWD
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?
 
   / Deere 855 Hydrostat pedal problem #2  
Sounds like the operator presence linkage is just barely hanging on the pedals. When you tap it hard, that is just enough to pop the pedal past the linkage.
 
   / Deere 855 Hydrostat pedal problem #3  
Check your parking brake. Sometimes a small press down on the parking brake button will solve this. There must be some kind of linkage from the parking brake to the pedals. If I put the brake on soft mine will do the same. Press down on the button and gone.
 
   / Deere 855 Hydrostat pedal problem
  • Thread Starter
#4  
Thanks, guys. Well, we're ramping up for hurricane preparedness, so it looks like I'll have a few days to play in the garage while the weather rages outside. I'll go thru that linkage carefully tomorrow, checking both the operator presence / seat stuff and the brake linkage.

BigEddy... what do you mean by parking brake button? The parking brake lever on the dash below the cruise control?
 
   / Deere 855 Hydrostat pedal problem #5  
I will be interested to see what you find here as mine seems to do exactly the same thing. One question, when it does this did you have the parking brake set? That seems to be when mine does it. I don't believe it's done it if I've been stopped and didn't have the brake set.
 
   / Deere 855 Hydrostat pedal problem #6  
The parking brake knob. If you set the brake softly then take it off then sometimes the linkage will still be locked and the pedals will not move without a stiff press. Reset the parking brake on tight and release and it goes away. Or. Press the knob down after releasing the brake. Presto.
 
   / Deere 855 Hydrostat pedal problem
  • Thread Starter
#7  
One question, when it does this did you have the parking brake set?

I hadn't been paying attention to this, but now I surely will. It's only done it 2 or 3 times. I often have my son sitting on the lap when I motor around the yard doing small jobs (never when using the loader or doing anything heavy), and I do make a habit of setting the brake when he's around, so that could be it.

The parking brake knob. If you set the brake softly then take it off then sometimes the linkage will still be locked and the pedals will not move without a stiff press. Reset the parking brake on tight and release and it goes away. Or. Press the knob down after releasing the brake. Presto.

Sounds like exactly the symptom I've observed, and maybe due to play / wear in the linkage? Have you owned your tractor since new? Will try this.
 
   / Deere 855 Hydrostat pedal problem #8  
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.
 
   / Deere 855 Hydrostat pedal problem #9  
Interesting. I need to use the tractor today to bring in coal/firewood. I'll have to experiment and see.
 
   / Deere 855 Hydrostat pedal problem #10  
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
 
 
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