Hydrostatic drive 853

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perry

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Does the hydrostatic drive on my 853 have a pressure relief valve?.
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Tazza

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Yes it will, ALL hydrostatic pumps have a relief valve set at around 5,000 PSI to prevent damage or bursting hoses. It will generally be behind a plug. It will simply be a spring and poppet. Each pump section will have one.
 

perry

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Yes it will, ALL hydrostatic pumps have a relief valve set at around 5,000 PSI to prevent damage or bursting hoses. It will generally be behind a plug. It will simply be a spring and poppet. Each pump section will have one.
I was leveling out a couple of 20 ton truck loads of clay and it stopped when I tried to pick up a large load, the tires were not spinning with the arms pushed all the way forward?. As I tilted up it gradually moved in worked fine.
Shouldn't the tires spin with the drive arms pushed all the way forward against a heavy load?.
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Tazza

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I was leveling out a couple of 20 ton truck loads of clay and it stopped when I tried to pick up a large load, the tires were not spinning with the arms pushed all the way forward?. As I tilted up it gradually moved in worked fine.
Shouldn't the tires spin with the drive arms pushed all the way forward against a heavy load?.
Thanks
Yes they should. If i push up against a large tree and push i just dig 4 holes with my wheels.
Te relief valves are just to prevent internal damage to the pumps or motors. In most situations i would suspect the relief would not open. 5,000 PSI is pretty darn high.
Did the machine bog down? Generally to get the pumps to go over relief the engine will bog down and probably stall. Still, you should get the wheels to spin.
 

skidsteer.ca

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Yes they should. If i push up against a large tree and push i just dig 4 holes with my wheels.
Te relief valves are just to prevent internal damage to the pumps or motors. In most situations i would suspect the relief would not open. 5,000 PSI is pretty darn high.
Did the machine bog down? Generally to get the pumps to go over relief the engine will bog down and probably stall. Still, you should get the wheels to spin.
would the arms lift?
sounds like a loose main drive belt to pumps and hydros
Ken
 

Tazza

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Yes, the arms and tilt worked just fine, I did install a new belt, could this be it?.
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It may be an idea to check that the belt tension is correct. It would explain the problems you describe.
 

skidsteer.ca

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It may be an idea to check that the belt tension is correct. It would explain the problems you describe.
The belts break in over 20 hours or so and often needs re tensioned, it drives both the pumps and hydros, but the pumps would require less power then the drives and the iggest demand would be when using both lift and drives at once.
The 853 does not have the spring loaded tensioner so it needs to be checked more often.
If you have it off check the oil level in the tensioner bearing to.
Ken
 

perry

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The belts break in over 20 hours or so and often needs re tensioned, it drives both the pumps and hydros, but the pumps would require less power then the drives and the iggest demand would be when using both lift and drives at once.
The 853 does not have the spring loaded tensioner so it needs to be checked more often.
If you have it off check the oil level in the tensioner bearing to.
Ken
Ken, Tazza.. you guys are right again!, the manual says to retension the drive belt after 5 minutes...WRONG. more like 8 hours. Just to be sure I drove up to tree and the tires dug 4 holes!!. The manual says something about a gauge tensioner?, The formula I've always used.........tighten belts enought so you can push the belt in the same thickness as the belt.
Is this acceptable?.

Perry
 
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