Chinese backhoe hydraulic pressure issue

[brettski]

Filter is between the tank and the pump, on the suction side.

 

[CJONE]

BTW, CJ.......since July 1976
(Slapped ya back)

a day or 2! Funny when you try to help someone look at the crap you get!

 

[CJONE]

Many professionals here must remember that not many folks have a set of pressure-flow gauges or pump test stands laying around for occasional use. "In the field" type diagnostics work best. Lending your expertise and experience on common faults will go further than pointing someone to a catalog of test equipment. Once the problem area(s) is/are identified then it's up to the owner to decide if further testing is worth the expense. Personally, I was surprised the OP had a hydraulic pressure gauge. Perhaps he needs help on where to locate the gauge and how to use a valve to get a proper reading without a flow gauge instead of hearing all the back slapping and about all your years of experience.

And that is why both of our posts suggested using a pressure/flow tester so he can quit guessing. I know my shop will loan a tester out and in most cases do the test for free if the customer buys the parts from us. As far as the backslapping? I was just curious because from WD's posts his recommendations are usually spot on and not guessing like a lot of posts. Your comments make people that want to help, change their mind. CJ

 

[CJONE]

As far as the pump being deadheaded. Either the pump is worn or very poorly assembled to bypass the full flow internally or something breaks, housing, input shaft, drive key ect. I wish you were closer, I would happily help you figure it out. CJ

 

[brettski]

There is a Deere dealer reasonably close to me. They guessed about $300 to send a field tech. If I can tow the tractor + backhoe in on a trailer, about 1/2 that. The weight of both is just within tow capacity of the trailer, buy my 1/2 ton truck will be huffing and puffing (if not gasping).
So....what about this possible "work-around".....
What if I first remove the pump and crack it open to look for abnormalities. How complicated can it be? I mean, what if I find a pinched or rolled O-ring or rubber gasket or something. What else would I look for that would be visible evidence of declined integrity? Or, is that crazy and a waste of time?

 

[dfkrug]

What if I first remove the pump and crack it open to look for abnormalities. How complicated can it be? I mean, what if I find a pinched or rolled O-ring or rubber gasket or something.

I open and inspect most of what I get from China, and I buy parts from there directly. I have
found flashing, poorly installed seals, etc. The pump is not that complicated.....open it up, if
you are so inclined.

 

[CJONE]

I got sent a D05 control valve that literally had machining debris falling out of the ports. Worked fine after cleaning out, just glad I found it before mounting it up to try to use it. CJ

 

[brettski]

BRETTSKI:

You should also make sure the vent in the cap is
not blocked

I assume you mean the filler cap (vent cap). What havoc can a blocked vent cap wreak, other than not allowing fluid expansion as it warms? Can it affect PSI performance, too?

 

[Xfaxman]

If the pump is designed to run with motor oil and you are using low viscosity hydraulic oil, it will not develop full pressure.

 

[brettski]

If the pump is designed to run with motor oil and you are using low viscosity hydraulic oil, it will not develop full pressure.

Factory recommended 46 weight hydraulic fluid. I am running AW46 Hydraulic Fluid, purchased at Farm and Fleet.