Ford 800 backhoe hydraulic problem

Hello and good morning, I have some hydraulic problems with my Ford 800 backhoe tractor. I believe that it is a 1953 model and it was all factory equipment until. I know there's the problem "until " a few years ago the hydraulic control valve for the front end loader was leaking internally and externally I replaced all the seals in it and it quit leaking externally and dripping on my boots, but the cylinders started to leak down and didn't seem to have the lifting power anymore. So I did some searching for a replacement control valve of the same valve that came on it originally, I did find used ones for like $250 and there wasn't any idea if they were wore out or worse than mine. So I started looking at aftermarket control valves (obviously overseas brands) so I originally planned on going with a 2 spool valve design that came on the tractor, but then I started thinking to myself hey if I have to refabricate some of my tractor to accommodate the new valve why don't I go with a 3 spool valve ( in case I ever needed to add something later). So I did just that and it worked perfectly solved leak down problem and no more oil soaked boots. A few months go by and I decided to build a grapple for my bucket, I start by watching some YouTube videos and different ideas on the subject and I come up with a plan and I built it ( I'm gonna try to upload some pictures) and I'm sorry about the long winded post, but I figure with the whole story maybe someone can help me with my problem? So I built it and I worked way better than I ever thought it would, but as used the grapple more and more I noticed that the hydraulics to the grapple cylinder really started to bog the engine down making it labor a lot. The rest of the cylinders on the front end loader worked normal just as they always have. So when I would use the grapple I would only open the valve enough for it to operate without killing the tractor, but I know that something isn't right with it. A few days go by and a good friend of mine offered to cut down some trees that were leaning over my storage shed while I was at work ( now keep in mind he helped me rebuild this tractor and I don't consider him a dummy) of course I told him to go ahead and use the tractor. He calls me and said that he started the tractor and the pump split (cracked) the housing, he never even moved the tractor and this happened. What could have caused this to happen?
 

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The relief valve didnt open witch cause hyd system to deadhead and the weakest point was the pump. Why the 3rd spool was bogging down engine is another question.
 
Thank you Shaun for replying, my original post was a long enough post so I'll try to go a little farther about the grapple hydraulics. The cylinder came off a bat wing bushhog mower they came with approximately 20 ft of used hydraulic hoses I consider them 1/4" inside diameter lines the hydraulic hose guy says they're 3/8 Id hoses, could that be restricting the flow? Although I don't remember the tractor bogging down while I was fabricating it testing it out. I will get more pictures of my valve assembly when I get home today. Thank you again.
 
To figure out what's causing the engine to bog down, I would try swapping the lines so that the spool that controls the grapple would control one of the other functions (lift or curl). That way you could see if the problem with bogging down the engine is related to that particular spool in the control valve or if it is the lines and/or cylinder for the grapple circuit.
 
I got it running tonight with a replacement pump that I had in the garage, the pump didn't dead head. Upon further inspection I think my friend may have pulled the diverter valve for the backhoe function, I removed the backhoe from the tractor in order to brush hog my field I got tired of tripping over the steel hydraulic lines that feed the backhoe so I removed them to and plugged off the diverter valve. So if that happened it definitely would have dead headed the pump. So I took your advice and switched the grapple cylinder lines with my bucket curl lines the bucket curled the same as it did on the original spool. The grapple cylinder did the same thing (bogged the engine down) so it's the hydraulic lines or the hydraulic cylinder. I'm going to disassemble the hydraulic cylinder tomorrow and examine it.
 
Are the hydraulic hoses old?

It iis possible the lining inside one of you grapple hoses is coming apart. If the lining is coming apart, it can block the flow and build pressure with out moving the cylinder. I chased a similar issue for two days a few years ago. Check the hoses.

It is also possible a piece of lining has broken off and is plugging a port some place in that circuit.
 
Hello and good morning, I have some hydraulic problems with my Ford 800 backhoe tractor. I believe that it is a 1953 model and it was all factory equipment until. I know there's the problem "until " a few years ago the hydraulic control valve for the front end loader was leaking internally and externally I replaced all the seals in it and it quit leaking externally and dripping on my boots, but the cylinders started to leak down and didn't seem to have the lifting power anymore. So I did some searching for a replacement control valve of the same valve that came on it originally, I did find used ones for like $250 and there wasn't any idea if they were wore out or worse than mine. So I started looking at aftermarket control valves (obviously overseas brands) so I originally planned on going with a 2 spool valve design that came on the tractor, but then I started thinking to myself hey if I have to refabricate some of my tractor to accommodate the new valve why don't I go with a 3 spool valve ( in case I ever needed to add something later). So I did just that and it worked perfectly solved leak down problem and no more oil soaked boots. A few months go by and I decided to build a grapple for my bucket, I start by watching some YouTube videos and different ideas on the subject and I come up with a plan and I built it ( I'm gonna try to upload some pictures) and I'm sorry about the long winded post, but I figure with the whole story maybe someone can help me with my problem? So I built it and I worked way better than I ever thought it would, but as used the grapple more and more I noticed that the hydraulics to the grapple cylinder really started to bog the engine down making it labor a lot. The rest of the cylinders on the front end loader worked normal just as they always have. So when I would use the grapple I would only open the valve enough for it to operate without killing the tractor, but I know that something isn't right with it. A few days go by and a good friend of mine offered to cut down some trees that were leaning over my storage shed while I was at work ( now keep in mind he helped me rebuild this tractor and I don't consider him a dummy) of course I told him to go ahead and use the tractor. He calls me and said that he started the tractor and the pump split (cracked) the housing, he never even moved the tractor and this happened. What could have caused this to happen?
Sounds like you have the valve plumbed incorrectly. Post a picture if your new valve and your plumbing.

Dan
 
Upon further investigation the grapple hydraulic cylinder part number (Bush hog 50047474) is a one way hydraulic cylinder. I got them from a salvage yard along with the materials used in building the grapple attachment. So if the seal in the cylinder is by passing fluid it would be fighting each other in theory. I also will post a picture of the hydraulic hose fitting orfice seems awful small in my opinion. Please keep in mind I'm working on a budget here so a lot of this is from a salvage yard, and I really appreciate your advice.
 

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Upon further investigation the grapple hydraulic cylinder part number (Bush hog 50047474) is a one way hydraulic cylinder. I got them from a salvage yard along with the materials used in building the grapple attachment. So if the seal in the cylinder is by passing fluid it would be fighting each other in theory. I also will post a picture of the hydraulic hose fitting orfice seems awful small in my opinion. Please keep in mind I'm working on a budget here so a lot of this is from a salvage yard, and I really appreciate your advice.
That appears to be one of the ubiquitous P80 control valves that you can get from many sources. They first started in Europe (Bulgaria) and are very popular. Lots of people now making clones. No problem there.

The valve has an inlet pressure relief which should be the primary protection for the pump. If it is set propetly and the plumbing is correct there should be no way to crack the pump by deadheading it.

The first think that jumps out is you are not using the power beyond port on that valve. If anything down stream of that valve is back pressuring the tank port it can/will prevent your inlet relief valve from opening and you can do some serious damage. Given your failure that seems like a very real probability.

The one way cylinders make me a little nervous . I assume you have two and one is used to open the grapple and the other to close it? If so and you have that plumbed correcyly there should be no issue there. And as I said above - the relief will prevent damage from deadheading any cylinder.

Apparently there is also a backhoe in the mix. Is it supplied by the same pump as the loader and if so how is it connected .

What is the diverter you mentioned? It also makes me very nervous. Why is it needed, and where is it in the mix?

Dan
 
The tractor came with a backhoe, after further investigation I found out the tractor had a live PTO and lift arms. I figured that if I wasn't using the backhoe that often why not remove it and utilize the PTO and 3 pt hitch. So I removed it, the diverter valve is plumbed between the pump and the F.E.L control valve it was built this way from the factory. I'm assuming that the engineers figured that the backhoe wouldn't be removed? The diverter valve sends fluid to the backhoe and the backhoe control valve has its own relief valve. When I replaced the original FEL control valve I made sure to plumb the diverter valve exactly as it was from the factory (yes I do plan on using the backhoe attachment again) so instead of having the extra steel and rubber hydraulic lines in the way I removed them and capped them off at the diverter valve. So essentially if the diverter valve is switched the hydraulic circuit has no relief valve (yes my fault for not thinking it through) after you mentioned "dead heading" the pump I started thinking about my friend accidentally pulling the diverter valve and not knowingly destroying the hydraulic pump. Of course this is all in theory. Have I asked my friend about this situation? No I haven't and probably won't either. Regardless pump was destroyed.
 

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This is the style of cylinder that I have on the grapple it's a standard tie rod cylinder with 2 fluid ports, 1 at each end. When I got these (2 of them) 1 cylinder had the hydraulic lines attached to each port, I guess I assumed that it was a 2 way cylinder but after looking up the part number the description says one way cylinder. I'm going to disassemble this cylinder and see if it actually is a "one way cylinder " or if I can get different packings (seals) for it. There is only 1 cylinder on the grapple attachment. I just want to tell you that I appreciate all the advice and information you have offered to me. Thank you Chris
 

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Upon further investigation the grapple hydraulic cylinder part number (Bush hog 50047474) is a one way hydraulic cylinder. I got them from a salvage yard along with the materials used in building the grapple attachment. So if the seal in the cylinder is by passing fluid it would be fighting each other in theory. I also will post a picture of the hydraulic hose fitting orfice seems awful small in my opinion. Please keep in mind I'm working on a budget here so a lot of this is from a salvage yard, and I really appreciate your advice.
That appears to be a common tie rod cylinder. In looking at the parts drawings, on the Bush Hog site I didn't see that it was specifically called out as a single acting cylinder. It looks to me like Bush Hog is using a double acting cylinder as a single acting cylinder. They use a breather in the base end of the wing cylinders, that part number, on several bat wing mowers. Gravity lowers the wings; power down is not needed so single acting is all that is needed.

Interested in seeing the fitting with the small orifice you mentioned and what the measurement of the orifice is compared to the hose size. Perhaps you got a restricted fitting in your system.
 
The tractor came with a backhoe, after further investigation I found out the tractor had a live PTO and lift arms. I figured that if I wasn't using the backhoe that often why not remove it and utilize the PTO and 3 pt hitch. So I removed it, the diverter valve is plumbed between the pump and the F.E.L control valve it was built this way from the factory. I'm assuming that the engineers figured that the backhoe wouldn't be removed? The diverter valve sends fluid to the backhoe and the backhoe control valve has its own relief valve. When I replaced the original FEL control valve I made sure to plumb the diverter valve exactly as it was from the factory (yes I do plan on using the backhoe attachment again) so instead of having the extra steel and rubber hydraulic lines in the way I removed them and capped them off at the diverter valve. So essentially if the diverter valve is switched the hydraulic circuit has no relief valve (yes my fault for not thinking it
I don't know what happened to kill your pump but I suggest you give that plumbing some serious reconsideration.

Whatever you do there should be no way for the operator to truly deadhead the pump. In operation cylinders deadhead all the time but the inlet relief in the control valve limits the pump pressure to a reasonable value and nothing gets damaged.

Your loader valve has an inlet relief and if it is placed first in the circuit and plumbed with a proper tank return there is NEVER any chance of doing what you describe.

Your valve has a Power Beyond port. Buy and install the powwer beyond conversion sleeve in the N port on your valve,. Then use that N port to power the backhoe and get rid of that diverter. This is how modern TLB tractors with open center hydraulics are plumbed and it is basically GI proof. Here is a line drawing of the plumbing, Top drawing is with backhoe connected and bottom is with it disconnected.

Use quick connects on the two hoses feeding the backhoe and put one male and one female on the backhoe side. When the backhoe is removed simply loop the N port hose back to the T line. There is zero chance of truly deadheading the pump. Worst case is the operator fails to loop back and the inlet relief in the loader will unload the pump to tank. Not desirable but it wont cause any damage unless left that way for a very extended length of time.,

Dan

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That appears to be a common tie rod cylinder. In looking at the parts drawings, on the Bush Hog site I didn't see that it was specifically called out as a single acting cylinder. It looks to me like Bush Hog is using a double acting cylinder as a single acting cylinder. They use a breather in the base end of the wing cylinders, that part number, on several bat wing mowers. Gravity lowers the wings; power down is not needed so single acting is all that is needed.

Interested in seeing the fitting with the small orifice you mentioned and what the measurement of the orifice is compared to the hose size. Perhaps you got a restricted fitting in your system.
A .030 orifice would not be unusual and if the control valve is properly plumbed will never be a problem of the sort described.

Dan
 
A .030 orifice would not be unusual and if the control valve is properly plumbed will never be a problem of the sort described.

Dan
Agreed, properly plumbed it wouldn't split a pump. However, I think it might give a noticeable increase in engine loading during operation compared to a full-bore fitting, at least some I have seen do.
 
Agreed, properly plumbed it wouldn't split a pump. However, I think it might give a noticeable increase in engine loading during operation compared to a full-bore fitting, at least some I have seen do.
I think its likely he spilt the pump by deadheading it. See my comments on plumbing.

I am not sure where the orifice is.

If its a breather on the unused end of a DA cylinder it's venting air and won't load the pump.

If its on a hydraulic line its being used for speed control and will load the pump. Making it bigger or eliminating it will defeat the purpose and increase cylinder speed.

Dan
 
I will look into that plumbing for sure! Thank you for the information. I'm pretty sure back in 1953 they didn't think the backhoe would be removed and the diverter valve served that purpose very well. I don't know why they put a backhoe and FEL on a tractor with a live PTO and operational 3 pt lift arms, my other friend has a 1962 Ford 2000 industrial backhoe/FEL and his doesn't have those options I guess that's why it's named "industrial "? But everything is almost exactly the same on his tractor as mine. I know that with the backhoe attached on my tractor the rear PTO Drive is not accessible. At one time I thought about modifying the backhoe as to be able to use a PTO driven hydraulic pump instead of the front mounted hydraulic pump. But I definitely will check into one of those " power beyond " attachments.
 
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.
 
I will look into that plumbing for sure! Thank you for the information. I'm pretty sure back in 1953 they didn't think the backhoe would be removed and the diverter valve served that purpose very well. I don't know why they put a backhoe and FEL on a tractor with a live PTO and operational 3 pt lift arms, my other friend has a 1962 Ford 2000 industrial backhoe/FEL and his doesn't have those options I guess that's why it's named "industrial "? But everything is almost exactly the same on his tractor as mine. I know that with the backhoe attached on my tractor the rear PTO Drive is not accessible. At one time I thought about modifying the backhoe as to be able to use a PTO driven hydraulic pump instead of the front mounted hydraulic pump. But I definitely will check into one of those " power beyond " attachments.
Here is the sleeve needed to convert your valve to power beyond operation.

https://summit-hydraulics.com/produ...eeve-for-p80g-series-summit-monoblock-valves/

Its only $30 and should not bust any budgets or pumps. You put it in the N port and use that port to power down stream devices. You MUST also use the T port to return exhaust and relief flow to tank as shown in my diagram.

Dan
 
I think its likely he spilt the pump by deadheading it. See my comments on plumbing.

I am not sure where the orifice is.

If its a breather on the unused end of a DA cylinder it's venting air and won't load the pump.

If its on a hydraulic line its being used for speed control and will load the pump. Making it bigger or eliminating it will defeat the purpose and increase cylinder speed.

Dan
I agree.

My main point was from looking at the parts breakdown, I think he has a double acting cylinder being used as single acting.

Beyond that I am just curious as to the size of the restriction he mentioned.
 

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