How much will a Bobcat 853 lift?

[busybeeman]

Hi, I am new to the forum but have been watching for a while. I have a 94 bobcat 853. To me it seems like the hydraulics for the lift arms and bucket are weak. I know that the lift capacity of the machine is 1700 lbs. I know it will pick that, but it will not pick up a full bucket of dirt. If you go by the specs it is supposed to raise the arms in 4 sec. it takes more like 6 sec. I feel like the hydraulics should be stronger. I am wondering if this is correct. I am thinking pressure relief valve or pump. Thanks for any input.

 

[Kermode]

An 853's back wheels will come off the ground long before you run out of hydraulic power. If your wheels are still on the ground when the hydraulics power out then you have a problem. I would hook a pressure gauge into the aux hyd quick connect and check pressure to start with. You may need a new hyd pump.

 

[busybeeman]

An 853's back wheels will come off the ground long before you run out of hydraulic power. If your wheels are still on the ground when the hydraulics power out then you have a problem. I would hook a pressure gauge into the aux hyd quick connect and check pressure to start with. You may need a new hyd pump.

The wheels will not come off the ground. Is it possible to be the pressure relief valve? The good thing is the pump is not to expensive.

 

[Tazza]

The wheels will not come off the ground. Is it possible to be the pressure relief valve? The good thing is the pump is not to expensive.

I believe the 4 seconds is for a machine without a bucket.
6 seconds isn't bad at all!

 

[busybeeman]

I believe the 4 seconds is for a machine without a bucket.
6 seconds isn't bad at all!

I put a tester on the aux hydro. When idle it is about 900 psi. When at full speed it goes up to 1500 psi but quickly drops down to 900psi. Is this the pump or something else?

 

[Kermode]

I put a tester on the aux hydro. When idle it is about 900 psi. When at full speed it goes up to 1500 psi but quickly drops down to 900psi. Is this the pump or something else?

I would say you need a new pump. If I recall correctly you should have 1800-2200 psi at idle. Pull your hydraulic filter, cut it apart and see how much brass and steel shavings are in there. Chances are it will be full of scrap iron. If the filter is clean, then you have an issue with the pressure relief valve.

 

[bobbie-g]

I would say you need a new pump. If I recall correctly you should have 1800-2200 psi at idle. Pull your hydraulic filter, cut it apart and see how much brass and steel shavings are in there. Chances are it will be full of scrap iron. If the filter is clean, then you have an issue with the pressure relief valve.

I have no experience with an 853. Is it a belt drive machine? If so, could this be a loose belt problem? Should hear a squeal if it's loose, but maybe not. ---RC

 

[Kermode]

I have no experience with an 853. Is it a belt drive machine? If so, could this be a loose belt problem? Should hear a squeal if it's loose, but maybe not. ---RC

853 is belt drive but if the belt is loose it will slip. The belt drives the hydrostatic as well so the drive motors will slow down too. When the belt breaks, you're walking.

 

[busybeeman]

853 is belt drive but if the belt is loose it will slip. The belt drives the hydrostatic as well so the drive motors will slow down too. When the belt breaks, you're walking.

I talked to the dealer today. They felt that the pressure relief valve is bad. It builds pressure then drops. I turned in the pressure adjusting screw and the pressure rose 200psi. They said it is common for the valve and not common for the pump.

 

[Tazza]

I talked to the dealer today. They felt that the pressure relief valve is bad. It builds pressure then drops. I turned in the pressure adjusting screw and the pressure rose 200psi. They said it is common for the valve and not common for the pump.

Could be a broken spring i guess. What is the damage on a new one?

 

[busybeeman]

Could be a broken spring i guess. What is the damage on a new one?

They said that is what they see, the spring breaks. It is $75 and has to be ordered. I should have it next week.