Ford 800 backhoe hydraulic problem

It will be after I get home from work in order for me to get a picture of the hydraulic hose fitting and line size, at the time I didn't even know if my grapple design was even going to work. I wasn't going to fork out $200 -$300 for new hydraulic hoses if I didn't have to.
Regardless of size or location that orifice did not split your pump.

Failure to ensure a proper relief is in the circuit split the pump.

Period.

Dan
 
First let me compliment you on the neat plumbing.

Now here are my suggested changes to your plumbing. Its cheap and will make the loader valve the primary "fuse" in the hydraulic circuit and prevent any future accidental deadheading and damage to the pump.

Put quick connects on the hoses going to and returning from the backhoe. When the backhoe is removed simply connect the tractir side supply and return hoses together to maintain the power beyond loop. Should you fail to do that the inlet relief in the loader valve will unload the pump into the filter and prevent damage to the pump. Virtually GI proof.

Dan

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Hey that's a great idea! I really like how you took the time to use the picture to point out where exactly everything needs to go. That's idea has been put next on the list, right after I get the grapple cylinder restrictions sorted out. Thank you Dan
 
Hey that's a great idea! I really like how you took the time to use the picture to point out where exactly everything needs to go. That's idea has been put next on the list, right after I get the grapple cylinder restrictions sorted out. Thank you Dan

You are more than welcome.

i will just add that if you run two hoses wirh quick couplers to the rear for the backhoe outlets and make them "permanent" you will have a general purpose power beyond rear outlet that you can use for other things. Lets say you had a senior moment and bought something silly like a 3pt log splitter you could plug it in just like the backhoe :devilish:

Dan
 
Ok I disassembled the "sister" cylinder, I have 2 of them and from what I can see is the seals ( packings) are good and it looks to be the same on either side of pressure ring (seal). I'm going to assume that these cylinders could be used as 2 way cylinders.
 

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So it's looking like the hydraulic lines are too small for it or restricted or other cylinder is messed up inside.
Why do you say that? I have seen nothing to indicate that is a problem. The cylinder will max out at whatever pressure the inlet relief is set at - factory default is 2500 PSI. That won't crack a pump.

Dan
 
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Along with the original post about what split the hydraulic pump was the question that I had changed the FEL control valve and installed a three spool valve. I had built a grapple for the bucket, the cylinder that I'm using came off a bush hog mower and it was only being used as a lift cylinder (one way). As I had mentioned earlier I noticed that it was really bogging down the tractor engine when it was being used. Shaun told me to switch the grapple lines at the control valve with another set of lines to another tractor function like (bucket curl) too see if it was the valve or something with the grapple hydraulic circuit. I did that and it wasn't the control valve. We had come to the conclusion that either the cylinder was by passing fluid or the hydraulic lines were restricted or collapsed or maybe just to darn small for the fluid being sent through them.
 
Dan this is the valve I installed on my tractor.
 

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Along with the original post about what split the hydraulic pump was the question that I had changed the FEL control valve and installed a three spool valve. I had built a grapple for the bucket, the cylinder that I'm using came off a bush hog mower and it was only being used as a lift cylinder (one way). As I had mentioned earlier I noticed that it was really bogging down the tractor engine when itw was being used. Shaun told me to switch the grapple lines at the control valve with another set of lines to another tractor function like (bucket curl) too see if it was the valve or something with the grapple hydraulic circuit. I did that and it wasn't the control valve. We had come to the conclusion that either the cylinder was by passing fluid or the hydraulic lines were restricted or collapsed or maybe just to darn small for the fluid being sent through them.
It is not hose size. You could havec1/4" hose on those cylinders c and it would not bog the engine down. Many grapplesxactislly Gome with 1/4" hose because it's a miniscule flow and the smaller hose is easier to manage.

If the cylinder is bypassing internally you would have a high pressure pinhole leak out the vent and things would be covered in oil.

You have a double acting cylinder- plumb it as such. I see two hoses on the grapple spool. How can that work on a cylinder plumbed for single acting control?

Dan
 
Dan this is the valve I installed on my tractor.
That's max rated pressure- not the relief setting.

I was not going to go here but...

Those valves also have BSPP ports. Are you using BSPP port adapters?.

Here is a link to a far more reliable seller that provides real specifications


Dan
 
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This specified sae -10 ORB for all ports except sae -12 ORB for outlet port (return). I'm using sae - 10 ORB to 1/2 npt on the spools, sae -10 ORB to 1/2 npt on the inlet (pressure port) and sae -12 ORB to 3/4 npt on the return port. Now I am going to remove the sae -10 ORB to 1/2 npt fitting on the pressure side and install a sae -10 ORB to 3/4 npt directly from the pump, in order to bypass the diverter valve entirely at this time. This is the fitting that is on my hydraulic hoses now (small hole) if I had to guess it looks like a 3/16th hole in it. Here's the hydraulic cylinder that I'm using (it originally was a one way cylinder) as you can see I plumbed it to work as a 2 way cylinder, the fittings on the cylinder are sae - 8 going to a 06 JIC male 90° elbow. There are some examples of the sae - 10 ORB fittings.
 

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The cylinder was a one way cylinder with a vent installed on the neutral (Unused end of cylinder), that is why I disassembled the other cylinder just to check the packings (seals) earlier post with pictures. Just to eliminate the possibility of it by passing the packings and theoretically fighting against itself.
 
The cylinder was a one way cylinder with a vent installed on the neutral (Unused end of cylinder), that is why I disassembled the other cylinder just to check the packings (seals) earlier post with pictures. Just to eliminate the possibility of it by passing the packings and theoretically fighting against itself.
I am looking at the picture of the hoses on the grapple. You seem to have two hoses coming from the valve into tees and two more going to the cylinder. That is not how you plumb a single acting cylinder. It looks like you may be feeding both ends of the cylinder simultaneously.

A single acting cylinder would be one hose from one port on the valve going to the base end of the cylinder. The rod end is not connected to anything.

I think that plumbing needs to be corrected. Make it double acting. One port goes straight to the base end with one hose. The other port goes straight to the rod end with a second hose. No tees or branches or interconnections.

The orrifices and hose sizes are fine if you plumb things correctly.

Dan
 
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There isn't any tees in the lines, they are zip tied to each other. But I just started thinking about the the quick couplers, it could be that I made a mistake and switched the lines while putting them together. Yes I made sure that they cannot be interchanged when unhooking the grapple.
 
Nope I traced the hydraulic lines to and from the control valve to the cylinder and back, did it twice they're plumbed correctly just like the loader functions push forward bucket dumps pull back bucket curls back. Push forward grapple closes pull back grapple opens. Here's some better pictures of the quick coupler set up.
 

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There isn't any tees in the lines, they are zip tied to each other. But I just started thinking about the the quick couplers, it could be that I made a mistake and switched the lines while putting them together. Yes I made sure that they cannot be interchanged when unhooking the grapple.
There isn't any tees in the lines, they are zip tied to each other. But I just started thinking about the the quick couplers, it could be that I made a mistake and switched the lines while putting them together. Yes I made sure that they cannot be interchanged when unhooking the grapple.
You don't use two hoses to connect a single acting cylinder

If thatcwas yourvintent it's just plain wrong. I don't know what you actually have but it's not single acting.
 

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