Ford 1700 3 pt lift problem

[Marinemammal]

I'm thinking something like this would work. What do you think?

Adjustable High Pressure Relief Valve, 20 GPM, 2500 PSI, 3/4” NPT

Adjustable High Pressure Relief Valve, 20 GPM, 2500 PSI, 3/4” NPT - FREE SHIPPING

summit-hydraulics.com

 

[JC-jetro]

I'm thinking something like this would work. What do you think?

Adjustable High Pressure Relief Valve, 20 GPM, 2500 PSI, 3/4” NPT

Adjustable High Pressure Relief Valve, 20 GPM, 2500 PSI, 3/4” NPT - FREE SHIPPING

summit-hydraulics.com

I like it on principal . How are you going to mount and plumb it? I wondered if you can remove the guts out of your relief device, plug the relief to the tank on the relief valve and then plumb the relief of this device to return to diffy using the square top plug on the diffy cover as pictured below. That could be done with a 3/8" high pressure hose. in that way, you keep the oem relief to cover all the holes on the side of the cover but can only act as a passage way to supply oil to the lift spool. I think that's doable. What do you think?

That square plug on the left and lower than the gauge just opens up to diffy so that could be perfectly used to return to tank.

PS. Can't argue with the price. Anything old and oem will be more expensive and may not be as good as your damaged one.

 

[Marinemammal]

The block between the old relief valve and the cover is configured so the oil can enter the 3-point control valve from one of it's ports. So oil from pump goes to the built-in relief valve on the loader valve. The oil leaves the loader valve through the new relief valve and goes to the power steering and then goes to the 3-point control valve through that block. That's the way I have it plumbed now, except without the new relief valve.

It occurs to me now writing this that the protection of the new relief valve may not be felt by the 3-point control valve after passing through the power steering. So the new relief valve probably has to be between the power steering and the 3-point control valve--if it's all in series.

I had thought the new relief valve should be mounted on the loader valve outlet. It's 3/4 pipe like the new relief valve. So it could T out of the new relief and go to the power steering and also to the 3-point--both of them dumping back into the diff. I think I like this configuration best.

 

[JC-jetro]

he block between the old relief valve and the cover is configured so the oil can enter the 3-point control valve from one of it's ports. So oil from pump goes to the built-in relief valve on the loader valve. The oil leaves the loader valve through the new relief valve and goes to the power steering and then goes to the 3-point control valve through that block. That's the way I have it plumbed now, except without the new relief valve.
ok. The first relief valve is to protect the pump and also adjusting the system pressure desired. if power steering as you plumbed has a lower pressure rating then your 3-pont would suffer some only as far as lifting capability. if it lifts , even slowly your heaviest implement then it will be okay in my estimation.

It occurs to me now writing this that the protection of the new relief valve may not be felt by the 3-point control valve after passing through the power steering. So the new relief valve probably has to be between the power steering and the 3-point control valve--if it's all in series.

I think in series then the lowest on will rule... activate first and higher one can not dump.

I had thought the new relief valve should be mounted on the loader valve outlet. It's 3/4 pipe like the new relief valve. So it could T out of the new relief and go to the power steering and also to the 3-point--both of them dumping back into the diff. I think I like this configuration best.
it sounds about right without seeing it in person. I posted a picture that shows 2 balls and check valve on the lift cylinder head and the one on the right with the stiffer and longer spring is the "Shock Relief" to protect lift piston seal. You already have a relief there.like i said your oem main relif was to protect the pump and nothing else.

 

[Marinemammal]

After several failures plumbing the new relief valve in, I tried it with only the loader and 3-point and got good results with both. The attached diagram gets everything to work. The 3-point and power steering work fine, but the loader is slow and jerky. I think the power steering may be the fault because it runs through 1/4 inch connections and everything else is 3/8.

I have tried running the power steering off of a T, but the the return line went to the transmission and nothing worked unless the steering wheel was turned slightly.

 

[JC-jetro]

After several failures plumbing the new relief valve in, I tried it with only the loader and 3-point and got good results with both. The attached diagram gets everything to work. The 3-point and power steering work fine, but the loader is slow and jerky. I think the power steering may be the fault because it runs through 1/4 inch connections and everything else is 3/8.

I have tried running the power steering off of a T, but the the return line went to the transmission and nothing worked unless the steering wheel was turned slightly.


View attachment 714851

Ok. I see. overall you have to have the relief after the pump. Saying that if the loader valve has a relief that is set about or lower than the main relief i Think it is okay specially when that relief over pressure is routed back to the tank. Power steering require less flow so 1/4" probably is okay and then 3/8" for the rest. what happens when you steered and stationary and then use the loader , is it jerky then also? any possibility of having trapped air in the loader cylinders? on my kubota I have actually two pumps with a common input shaft. the smaller pump is for pto and power steering so it is dedicated from loader and 3 point. I know if on one circuit they will have a priority valve to separate the circuits a bit. your situation is like having shower and a flush valve for the toilet on same circuit where one can affect both if used simultaneously.

I think I would just be okay with it as long as it works.

On a separate item, we were trying to figure out the wallowed hole in the relief device. I kept all the old hyd part from when I overhauled my pump in a coffee can. I went and looked at what i had. A that time my NH dealer was close and the counter part lady was very nice and they had everything in stock. I ended up buying a seat for the relief device in case i needed it. it was very cheap, the dang thing now is $146, can you believe that? Anywho, I ended up not using it, so I took a close look at it. As the pic might show below there is a conical seat on the inside that faces the wallowed hole. it is perfectly round and conical against the poppet and unless the tip of the poppet hits the body of the valve, don't know what else could have messed the hole? the poppet is hardened where the body of relief device is not. At any rate it should not matter as the seat and poppet are doing over pressure control. I just let the relief be. As an assembly that relief is $460, yikes.

One question, what fluctuation do you at the gauge when you raise the 3 points all the way up and down, loader up and down and curl all the way while steering? if under all those condition the pressure does not exceed 2000 psi I think you are good. Damaging the pump is not the last thing you need to do.

 

[Marinemammal]

Earlier, I took a close look at that relief valve seat and it looked in good condition--definitely cone-shaped. I thought that the ragged hole and surrounding area may be allowing oil to get around the seat. I was still able to hear that valve making some noise while trying to figure out the best way to configure the new plumbing. I adjusted it all the way down, and that did not stop the noise until I added an O-ring under the seat.

The gauge never exceeds 1600 psi that way it is set. With normal use, it is usually under 500 psi.

I will go try to crank the steering while raising the loader and see what happens.

 

[JC-jetro]

Earlier, I took a close look at that relief valve seat and it looked in good condition--definitely cone-shaped. I thought that the ragged hole and surrounding area may be allowing oil to get around the seat. I was still able to hear that valve making some noise while trying to figure out the best way to configure the new plumbing. I adjusted it all the way down, and that did not stop the noise until I added an O-ring under the seat.

The gauge never exceeds 1600 psi that way it is set. With normal use, it is usually under 500 psi.

I will go try to crank the Goodwhile raising the loader and see what happens.

Good , I think you are gaining on it. As long as it works and now you are well aware of the limitation. If 1600 psi picks up your heaviest 3 point load then there is no reason to exceed it. Remember lift piston has a relief on the piston head which is a good thing when you hit a bump or depression as you drive with a heavy load on the back. it just momentarily releases some pressure spike and then pump will fill it right back. persistence almost always pays, good job.

P.S. good idea to put an oring to seal the back of the relief against the seat to limit leak by, something to remember.

 

[Marinemammal]

After trying it out again, everything seems to be working fine--loader is faster and not jerking. One strange thing happened, while cranking the wheel all the way, and trying to lower the loader, it went up instead--somehow getting some feedback. And when I tried to float it down, it went up and the pressure went above 2000 psi. Very strange, but not something that would normally happen.

I appreciate all the help. I really learned a lot about the hydraulic system.

 

[JC-jetro]

Hmm , a bit strange. Flow in case of gpm or even electrical always take path of least resitance. I think what happened was increasing the pressure caused fee back on other circuit or some intenal leak in the loader spool feeding a different circuit. I think you have to draw a flow chart and look at all the possibilities and what happens when you do combination of stuff. That's why I suggested it just to to see. Would you know by any chance if your power steering has a relief ? One thing is the release pressure setting per factory is 2130 psi and I am sure it has at least %10 safety fudge with it and you are well below that. I know we were trying different things to have situational awareness and as we learn something that causes it to have heart attack, then let's try not do it. it is always good to know what "not to do". You hardly ever need to steer hard left or right and then use loader at the very same time.

You are welcome, I also learned a few or if nothing else satisfied my curiosity.

 

[Marinemammal]

After several days of trying different plumbing arrangements, nothing seemed to work. I drained the oil and cleaned the screen, replaced the used (but clean-looking) oil and it worked fine--for about 20 minutes. This is confusing, because the screen looked clean (before cleaning it) as did the oil. Even after cleaning the screen, if I removed the banjo bolt at the screen, very little oil would run out--maybe a stream about 1/8 inch. After running for 20 minutes the hydraulics quit, and hardly any oil would run out with the banjo bolt removed. So I installed a 3/4 inch plastic threaded pipe in the banjo hole (it fits) and blew air back through the screen and everything worked again--for about 20 minutes. So I drilled a 3/8 inch hole in the end of the screen cylinder and everything works fine and it seems like it's going to stay that way. The loader is faster and better than ever.

I know this is not a good idea, but I didn't know what else to do. So my plan now is to get new oil, plug the drilled hole with a bolt and drill 1/16 inch holes in the end of the screen--36 of them if there's room. I would like to add an external oil filter on to the system, but don't know how to do it since all the external lines are subject to 2000 psi.

It's plumbed like this. Pump-----Loader-----Relief Valve (relieves to trans)-----Power Steering----Three-Point

As in my previously attached drawing...

 

[JC-jetro]

After several days of trying different plumbing arrangements, nothing seemed to work. I drained the oil and cleaned the screen, replaced the used (but clean-looking) oil and it worked fine--for about 20 minutes. This is confusing, because the screen looked clean (before cleaning it) as did the oil. Even after cleaning the screen, if I removed the banjo bolt at the screen, very little oil would run out--maybe a stream about 1/8 inch. After running for 20 minutes the hydraulics quit, and hardly any oil would run out with the banjo bolt removed. So I installed a 3/4 inch plastic threaded pipe in the banjo hole (it fits) and blew air back through the screen and everything worked again--for about 20 minutes. So I drilled a 3/8 inch hole in the end of the screen cylinder and everything works fine and it seems like it's going to stay that way. The loader is faster and better than ever.

I know this is not a good idea, but I didn't know what else to do. So my plan now is to get new oil, plug the drilled hole with a bolt and drill 1/16 inch holes in the end of the screen--36 of them if there's room. I would like to add an external oil filter on to the system, but don't know how to do it since all the external lines are subject to 2000 psi.

It's plumbed like this. Pump-----Loader-----Relief Valve (relieves to trans)-----Power Steering----Three-Point

As in my previously attached drawing...

This is perplexing saying the least.

1. it seems the pump is having a hard time maintaining the prime. This is either suction restriction or pump gear to case not in tolerance causing slippage (oil)
2. with banjo removed at the screen you should have a stronger release of oil. That could be if your oil is too thick or screen blockage and yet your screen is clear after the inspection which does not make sense.
3. I think filter on the discharge side of the pump is a very bad idea and the reason you mentioned. More important than that is the purpose of the filter is to protect the pump and nothing else. With no filter in the suction you would run a risk of sucking junk and metal shaving in the inlet of the pump which obviously really bad.
4. You made a bypass by drilling a hole that in turn lowered the suction resistance and helped the pump to maintain the prime.
5. I would drill the holes on top of the screen rather than end or bottom, thinking crap would settle on the bottom of diffy and the oil 3 inches or so from bottom of diffy wold be inherently claner.
   
   did you clean and inspect the floor of diffy after removing the screen? on mine i had a 1/2" thick layer of sludge the very first time I did the oil change. Perhaps it was the very first time ever for the tractor. My ford is 40 years old and I owned it in the last 16 years. The second time I did the oil change there were hardly any slime. I sure hope right oil would help your situation. just keep us posted with your progress. Good luck.
   

 

[Marinemammal]

I didn't try to clean it out--but should have. I have done a thorough cleaning of it not long ago. I am using the recommended oil--tractor hydraulic transmission oil recommended for Ford M2C 134-A. I did try to see if there was a viscosity difference between the used oil and the new oil by drilling a 1/8 inch hole in a soup can and timing the oil flowing out. It was about the same--3.5 minutes for about 10 ounces of oil.

I was using the cheaper 303 oil (due to all the oil changes) which may be a less viscous oil and it seemed to work longer before the hydraulic system quit--6 months to a couple years depending on use. Maybe I can find some new 303 and test it with my soup can.

One of the first symptoms of the hydraulics stopping working was that the bucket would not go down with the the tractor off. It would normally relax down after turning if off by pushing the lever. And since I don't believe that this action has anything to do with the screen on the pump intake, I don't know what to make of it.

 

[JC-jetro]

I didn't try to clean it out--but should have. I have done a thorough cleaning of it not long ago. I am using the recommended oil--tractor hydraulic transmission oil recommended for Ford M2C 134-A. I did try to see if there was a viscosity difference between the used oil and the new oil by drilling a 1/8 inch hole in a soup can and timing the oil flowing out. It was about the same--3.5 minutes for about 10 ounces of oil.

I think cleaning is for sure better, How much better?? can't tell you. Screen allows oil to filter out from all sides and since the filter is mounted horizontally in the diffy then I would think muck and crap in the bottom tends to collect to the bottom more than top to add more or less friction to oil flow. I like your approach to quantify things, comparing apples to apples with your can experiment.

I was using the cheaper 303 oil (due to all the oil changes) which may be a less viscous oil and it seemed to work longer before the hydraulic system quit--6 months to a couple years depending on use. Maybe I can find some new 303 and test it with my soup can.

I really hope the main culprit was wrong oil and by oil change it will only could get better. you have done several things to your pump and I hope it does not have intermittent issues.

One of the first symptoms of the hydraulics stopping working was that the bucket would not go down with the the tractor off. It would normally relax down after turning if off by pushing the lever. And since I don't believe that this action has anything to do with the screen on the pump intake, I don't know what to make of it.

The only thing that could be the reason is that the oil is trapped in that cylinder well and that is how it should be . Your particular issue really points the finger to loader control valve. The bucket generally should not come down if the control valve seals and cylinder seals are okay. if it goes down on it's on then it is a bit of seepage and leak of the piston or control valve. Here you said " bucket would not relax with the tractor off and lever pushed in", in this situation then there might be blockage in the return path. This is so difficult to pinpoint, just imagine if some piece of teflon tape used to put the taperd joint together and you have bits and pieces floating in the system. I just wonder what permanent or momentarily it can do to a hydraulic system that is pumping constantly and in your case around 5.3 gpm no matter what as long as the tractor is running.

 

[Strikeout692]

JC I noticed in one of your earlier posts that you had pictures of the lift cylinder and piston when you replaced the seal. My question is when you take the 6 bolts off the piston housing does the cylinder and piston assembly come out with the housing? I have a shop manual but it does not go into detail about this. Also what is necessary to do to seperate the piston and how big a job is it to replace the assembly into the tractor after the seal is replaced. I figure since you have done this procedure you probably can pass along the do's and don'ts to get the job completed correctly. Ray

Do you happen to have the part number for the seal? Same issue here

 

[Strikeout692]

I wish I had taken pictures now! It was a bit hard to be the mechanic and the photographer too! But yes, it was an O-ring and a nylon/teflon seal -- two different part numbers. If you want I can go hunt the invoice and get the numbers...

I need the part numbers if you have then for the o ring and seal.

 

[JC-jetro]

I need the part numbers if you have then for the o ring and seal.

Part #19 is the seal, SBA050309012. You can refer to the attached PDF for all Lift cover components.