JW03 back hoe on Jinma 284 le weak hydraulics? please advise.

[BryanMitchell]

Hey group,

Please relieve some of my "freak out."
I just bought a used Jinma 283 le today and the backhoe hydraulics are causing me to have a mini stroke. I picked up the tractor and the back hoe was not attached. I personally hooked up the auxiliary pump to the little removable plate area above the PTO. Back hoe worked while at the guys house so we loaded it onto a trailer hauled it 15 miles down a gravel road, unloaded it and started playing with my new toy and the dang thing started fine then just seemed to loose all pressure. I got about half of a scoop of dirt in the dipper and it couldn't even pick itself back up. I thought it may have had low fluid so I checked the on board hyd. tank and added about a liter, that didn't change things either. I shut the tractor down for a couple of minutes and looked things over, no leaks, or anything. So I started it back up and for about 3 minutes, or until I started moving the motions around again it had power then just died off again.
It acted like there may have been air in the lines I think or maybe the little pump wasn't turning fast enough to keep up with the demand? It didn't seem to matter what the rpms were either.
Is it possible that air could have gotten in, and how long should I have run it to get the air out? I also noticed when I hooked it up that when I unbolted the little cover plate that the pump mounts up to no hyd fluid came out like I was expecting, the guy said that little area should refill after the pump starts turning, if that is still empty could that cause this issue?
I called the guy and asked if it had ever done this to him and of course it hadn't. I plan on taking off the pump to ensure it is actually turning tomorrow...???
thanks in advance for any advice.
Bryan

 

[Ricks284]

Sounds like you're not getting enough hyd fluid flow. Is there a filter in that system? Maybe the trip down the road shook something loose that clogged it.

 

[BryanMitchell]

I'll check tonight, I didn't notice a filter on the parts book?

 

[erj]

Bryan,
The connection on the tractor where you connected the backhoe pump is called the “auxiliary PTO”. There is no hydraulic fluid involved. It is a mechanical connection. That connection turns the pump to produce hydraulic pressure for the backhoe. It draws fluid from the backhoe’s hydraulic tank, pressurizes it and feeds it to the backhoe control valves.
Since the connection is mechanical, the speed of the pump is driven by the speed of the tractor engine.

Please post pictures of your backhoe.

 

[RonMar]

A loose fitting on the suction side of the pump could be drawing air into the system. Is the pump making noise (howling/squealing) when you load it up? That would indicate air and cavitation in the pump. Another possibility is you dislodged something in the system and it clogged the pressure relief valve and that is keeping you from building pressure.

 

[Affordable]

Sounds like the relief valve on the valve bank is not set properly or has debris in it, we do not have many parts for those backhoes but the relief valves were a issue and most of the time just need adjusted or cleaning

Tommy
Affordable Tractor Sales
"Your Jinma Parts Superstore"
Home of compact Jinma, Foton, and Koyker Tractors and Parts, Wood Chippers, Backhoes - Affordable Tractor Sales Company