Hydraulic Hose Removal

plaindriver · July 30, 2013, 09:34:56 AM

I have a small JD tractor that I bought new 28 yrs ago. It has been bullet proof, only maint so far is oil changes, repl batt once, and hyd fluid. Now, it has 650 hrs on it, and the hydraulic cylinders that control the "tilt" function on the front bucket seem lethargic. So, I want to remove them and take them to the hyd cyl shop to have the seals replaced. Problem is disconnecting the old hoses. There are two metal "right angle" fittings on each cyl, with a female union on each. First I sprayed WD40 to the threads. Then I tried turning the union while holding the male end of the hose still. No joy. Wouldnt budge. I thought of using 30" long copper pipes over the wrenches as cheaters to add torque, but worry about breaking that rt angle fitting. I also thought about using a air impact with 'crows foot' wrench heads, but am worried about collateral damage. I am leery to force the issue because the tractor is still quite usable in its current condition. I just want to improve the tilt but dont want to make a major problem out of a small issue. Any suggestions?

Hilltop366 · July 30, 2013, 10:00:36 AM

The fitting look like they are in pretty good shape, I don't think rust is stopping them from coming apart.

Sometimes if you put the wrenches on the fitting and hose so they are close enough together that you can grab both wrenches with your hands and pull them together or put a rod in the boxed end and twist the wrenches to loosen the nut it may work, another way would be to put the wrench that is on the hose against your body (it might help to put a board in between yourself and the wrench) then put the wrench on the nut about 30° away from you so you can get both hands on the wrench and pull the wrench towards you.

Keeping the angle between the two wrenches low will reduce the stress on the angle fitting.

grweldon · July 30, 2013, 10:28:48 AM

I wouldn't worry too much about damaging the right-angle fitting, the ports in the cylinders appear to be standard NPT (National Pipe Thread), possibly 1/2-18 NPT or 3/4-14 NPT. The fittings should be readily available. I would be more concerned about the hex on the hose stripping or the hose threads breaking off. It also looks like the 90 deg. part is another NPT fitting screwed in to the fitting on the cylinder. If this is the case, this horizontal (centerline) fitting will unscrew from the vertical (centerline) fitting on the cylinder. I am not completely sure about this and I don't want my suppositions to cause you to damage your cylinder but that's what I see. Without being there it's hard to be sure.

Not to stir the pot contradicting Hilltop, but it looks to me as if rust is exactly why the fittings are being difficult to remove. The industry has switched to stainless steel these days and use a different style connection to the hose with the NPT thread on the cylinder end. Not that it matters at all, but that cylinder doesn't look like an industry standard cylinder. It looks as if JD made those themselves or had a vendor make them to their specs, thus the primitive (read "cheap") look and hose attachment. I suspect that if they would have used a vendor supplied industry standard cylinder, you may not be having issues with it. Of course, I guess 28 years is an acceptable life expectancy? Pardon my rambling on, I'm at work with nothing to do... If the rant doesn't help, I hope it provides some bit of useful information! ;)

pigman · July 30, 2013, 10:47:07 AM

My experience is that with that type of fitting it would be easier to loosen if you held the female fitting and turned the male fitting. The female fitting has two areas of friction and the male fitting only has one area of friction. Of course as soon as it turns a small amount, the female fitting is the one that must be turned.

calw1izl · July 30, 2013, 11:30:59 AM

Plaindriver,

Those are standard swivel 90 deg fittings with a touch of age and subsequent "set". Try taking a small ball-peen hammer and lightly tapping around the large hex nut which attaches to the hose end. This may be enough to shock it enough to make it a bit easier to break loose.

Another thing that works well is to use a small pipe wrench on the hose nut end which will give you a wider bite and you will find the nut size and hose adapter flare to be about the same and this will spread the torque out a bit with less change of spinning on the "nut" portion of the hose end. A shot of Blue creeper or your favorite penetrating fluid will also help. Good luck.

beenthere · July 30, 2013, 11:39:30 AM

A great place for the Blue Creeper (the WD-40 just gives it a light oily coating). ;)

Give pigman's suggestion a serious thought after some ball peen taps as Calw suggests.

tractormanNwv · July 30, 2013, 12:06:04 PM

If you back your hammer up with a sledge you will concentrate more force on the nut and not the bottom of the fitting where it screws into the cyl port, just like using a hammer an dolly doing body work. That is a standard 1/2" npt / #10 JIC style fitting, use a good backup on the hose and a good wrench on the fitting nut and just put some backbone into it....it's gonna be tight so don't be afraid of it. I deal with them fittings quite often on these RR bridges, just don't pull your elbow / shoulder out of socket.

Jim

thecfarm · July 30, 2013, 01:49:13 PM

650 hours in 28 years.

Not that it matters,but I put more than that on mine in a year. That tractor is still brand new. ;D

sandhills · July 30, 2013, 02:02:42 PM

Quote from: thecfarm on July 30, 2013, 01:49:13 PM
650 hours in 28 years. Not that it matters,but I put more than that on mine in a year. That tractor is still brand new. ;D

:D :D Kinda what I was thinking, I was hoping I missed another 0 at the end and maybe a 1 on the front ;). Try any of above suggestions, they get tighter over the years (ok, I get weaker) but you won't hurt anything and it will take some serious torque.

plaindriver · July 30, 2013, 04:06:19 PM

I think it just hit 650 yesterday. Them is orig hrs too. It had 498 a yr ago when I moved onto this 10 ac parcel in Tn. Thats why there are so many hrs on it currently. When I lived in Kalif, for the first 27 yrs of its life, I had a 3/4 ac lot. I had far less need for it there, obviously. Its always lived indoors too. I forgot to confess, I did replace the front tires in the spring, at the 570 hr point. The rear tires are orig. I think the front tires wore so quick cause my driveway in Ca was 260' long, concrete. Did a lot of maneuvering on it.

PS: How many hrs would it take to be considered a "high mileage" tractor, 28 yrs old? Im guessing 2500 or so.

Hilltop366 · July 30, 2013, 04:23:13 PM

Quote from: grweldon on July 30, 2013, 10:28:48 AM

Not to stir the pot contradicting Hilltop, but it looks to me as if rust is exactly why the fittings are being difficult to remove.

Pot not stirred gr, but you guys down south have no idea what rust is like in my part of the world unless you have seen it. Between the salt air, wind blown sea water (in a 50-60 mph wind my house windows turn white), road salt and 80-100% humidity all spring and summer we are in one of the worst places for rust. The cars on the top of the pile at the junk yard are 8-10 years old if they have never been under coated.

Back to the fitting I'm betting that under the fitting after it is unthreaded it will be like new, there may be a little rust around the edges but not enough to impede removal much.

Thats my guess.

p.s. I have heard that in the automotive industry Atlantic Canada is known as the "rust bowl"

DaleK · July 30, 2013, 04:33:31 PM

Quote from: plaindriver on July 30, 2013, 04:06:19 PM
I think it just hit 650 yesterday. Them is orig hrs too. It had 498 a yr ago when I moved onto this 10 ac parcel in Tn. Thats why there are so many hrs on it currently. When I lived in Kalif, for the first 27 yrs of its life, I had a 3/4 ac lot. I had far less need for it there, obviously. Its always lived indoors too. I forgot to confess, I did replace the front tires in the spring, at the 570 hr point. The rear tires are orig. I think the front tires wore so quick cause my driveway in Ca was 260' long, concrete. Did a lot of maneuvering on it.

PS: How many hrs would it take to be considered a "high mileage" tractor, 28 yrs old? Im guessing 2500 or so.

Ummmmm....
My "new" tractor is an 06, has 6300 on it. Next older one is an 02 with 9100 and something. Parted my old 6400 loader tractor out four, almost 5 years ago, it was a 95 with 18,000 hours on it.

A decent tractor should get 10,000 hours before you even have to do any major work on it.

Something to try with hydraulic fittings... if you try to turn it tighter before trying to loosen it, it'll often loosen easier. After that I'd go with at least an 18" pipe wrench.

caper · July 30, 2013, 04:41:35 PM

Put a little heat to the swivel,just don't burn the hose. But if you are replacing the hose no big deal, also before you put new one on take some emery cloth to the mating surface on to get rid of the corrosion around the fitting.

nk14zp · July 30, 2013, 05:37:54 PM

Quote from: tractormanNwv on July 30, 2013, 12:06:04 PM
If you back your hammer up with a sledge you will concentrate more force on the nut and not the bottom of the fitting where it screws into the cyl port, just like using a hammer an dolly doing body work. That is a standard 1/2" npt / #10 JIC style fitting, use a good backup on the hose and a good wrench on the fitting nut and just put some backbone into it....it's gonna be tight so don't be afraid of it. I deal with them fittings quite often on these RR bridges, just don't pull your elbow / shoulder out of socket.

Jim

Do what Jim said it will work.

red oaks lumber · July 30, 2013, 09:59:13 PM

use a torch and heat the fitting, your wrench should loosen it right up.

Brucer · July 31, 2013, 12:40:52 AM

Another JD 750 owner!

Great machines. Mine is 32 years old and has 2000 hours on it -- mainly from plowing snow.

I've had to change a few hoses on the cylinders and I found the fittings to be very tight. Just used a pair of long-handled wrenches and excessive force. As soon as they broke free they unscrewed easily. I've never had to use a torch.

I do keep a couple of those right angle fittings in the spares box just in case something goes wrong when I'm changing a hose.

ScottAR · July 31, 2013, 12:57:54 AM

The hammer tricks stated above work like magic. Also the pipe wrench trick. My 1050 has the same style fittings and I've never had trouble finding hoses.

sandhills · July 31, 2013, 02:27:43 AM

Plain driver, I'm a farmer so I expect our tractor uses are much different but it's not much for me to put anywhere from 400 to 500 hours on both of my 2 main tractors in a year, that's not counting what the smaller tractors we have do. My dad has a (I believe) '64 JD 4010 that probably has around 30000 hours on it, engine has been rebuilt once, needs some hydraulic work, haven't figured out what exactly yet but still runs strong.

plaindriver · July 31, 2013, 10:35:05 AM

Since you also have a JD 750, Im wondering if you have ever repl the seat. Mine has some rips and the foam escaping in a couple of spots. The way it attaches is not generic to the seats I see on sale at Tractor Store. Am I better off to just take it to a reupholstery guy?

blackfoot griz · July 31, 2013, 08:53:31 PM

Quote from: plaindriver on July 30, 2013, 09:34:56 AM
I have a small JD tractor that I bought new 28 yrs ago. It has been bullet proof, only maint so far is oil changes, repl batt once, and hyd fluid. Now, it has 650 hrs on it, and the hydraulic cylinders that control the "tilt" function on the front bucket seem lethargic. So, I want to remove them and take them to the hyd cyl shop to have the seals replaced. Problem is disconnecting the old hoses. There are two metal "right angle" fittings on each cyl, with a female union on each. First I sprayed WD40 to the threads. Then I tried turning the union while holding the male end of the hose still. No joy. Wouldnt budge. I thought of using 30" long copper pipes over the wrenches as cheaters to add torque, but worry about breaking that rt angle fitting. I also thought about using a air impact with 'crows foot' wrench heads, but am worried about collateral damage. I am leery to force the issue because the tractor is still quite usable in its current condition. I just want to improve the tilt but dont want to make a major problem out of a small issue. Any suggestions?

I am just curious, are the cylinders themselves leaking? From what you described--and I could be wrong--it sounds like the problem is upstream from the cylinders. I would be tempted to remove any attachments on the front end and see if one cylinder extends and retracts faster than the other. Upstream from the cylinders, there may be some form of a flow divider--maybe there is a problem there where one side is not getting the flow that the other is possibly causing your problem.

Just a guess though!

Al_Smith · July 31, 2013, 09:03:41 PM

You put a big enough wrench on that thing it will come loose .---or break one .

beenthere · July 31, 2013, 09:32:50 PM

Also, as blackfoot griz suggests to look beyond the dump cylinders, if you have a regenerative hydraulic circuit on the bucket and don't know how it is supposed to work, then the bucket dump can give the impression it is "lethargic".
I suspect that it does, but don't know that for certain.

This is designed to dump fast, but if the lever to dump isn't moved all the way to "dump" position, the bucket may go part way and then lay limp for a short time.
It is a great feature, but can be puzzling to someone who doesn't know how it functions.

ScottAR · July 31, 2013, 11:30:34 PM

My 1050 acts in the manner you describe. I was never really sure if it was as you say or the pump couldn't pump fast enough for the system as it's only 8-9 gpm.

logloper · August 01, 2013, 08:53:51 PM

You can test the cylinder without removeing it. You are looking for fluid bypassing the packing inside the cylinder. If its not bypassing, or leaking outside the cylinder housing, then the cylinder is fine and you have another problem. Curl your bucket all the way up, and prop it. Undo the hose at the top of your cylinder, leave it off. Curl your bucket again, it shouldn't move since you already curled it all the way. If its bypassing the packing inside, you will have fluid come out the open fitting. Easy test

Brucer · August 02, 2013, 12:27:01 AM

Quote from: plaindriver on July 31, 2013, 10:35:05 AM
Since you also have a JD 750, Im wondering if you have ever repl the seat.

I replaced mine about 10 years ago. The upholstery wasn't too bad but the back was starting to buckle (from leaning on it all the time as I climbed aboard). A generic one wouldn't fit so I ordered a replacement from the JD dealer.

There's no regenerative circuit on the cylinders. They are all very basic: direct fluid into this line to extend, direct it into the other line to retract.

Another way to check for internal leaks on the pistons is to hook the bucket under something that's too heavy for the tractor to lift, then try to lift if anyway -- for a couple of minutes. Hydraulic fluid will divert back to the transmission through the relief valve. If the piston seals are leaking oil will squeak past them and the cylinder will get hot to the touch. If one cylinder is leaking more than the other, you'll get a noticeable temperature difference between the cylinders.