Matching Hydraulic Hoses

[JeffroL]

I've got an old John Deere 500C backhoe and I've removed 6 hydraulic hoses (with much effort). One had a pinhole leak and the others looked very rough. So I just pulled them off. The problem is that I have no idea how to match these hoses to new ones. I do not know their max operating pressure for example. I found 3500psi hoses at Tractor Supply, but don't know if they are sufficient. The hoses appear to be 1/2" diameter, but then I learned the outer diameter may be the same for 5/8" vs 1/2" hoses. So I have no idea now.

Help! Is there any way to find the specficaitons for these lines? Photos of the *very* similar hose I found at Tractor Supply. But again I have no idea if these are correct - and I do NOT want to do this twice

-Jeff

 

[Fallon]

I'm unaware of any tractors that operate significantly over 2,500psi. Some skid steers run at 3,500psi, excavators can be double or triple that. So basically a 3,500psi rated hose will be fine on a tractor.

You could cut one of the old hoses in half with a hacksaw & measure.

 

[JeffroL]

Shoot..mistyped that. It is a backhoe not a tractor. I don't know if that makes a difference in the hydraulic pressure

 

[LouNY]

I woundn't worry much about the pressure rating as the threads, are they npt, bsp, sae?

 

[JeffroL]

I woundn't worry much about the pressure rating as the threads, are they npt, bsp, sae?

That's the kind of question I'm not educated enough on the subject to answer. I did carefully compare the hoses vs. the ones at tractor supply and the threads look identical. I even "threaded" them together by holding them side by side and the threads connect perfectly.

 

[/pine]

The pictures of the hose ends are "male pipe" (NPTF) ...note the chamfer...this will allow the use of female pipe swivels (NPSM)

note:

National Pipe Straight Mechanical (NPSM) fittings are similar to NPTF, except they have a parallel thread and seal on an internal 30 degree seat.

A properly chamfered NPTF male fitting will mate with a NPSM female.

Steel Fittings - DiscountHydraulicHose.com

here is a size chart:

https://www.discounthydraulichose.com/v/vspfiles/downloadables/thread_guide.pdf

 

[JeffroL]

The pictures of the hose ends are "male pipe" (NPTF) ...note the chamfer...this will allow the use of female pipe swivels (NPSM)

note:

Steel Fittings - DiscountHydraulicHose.com

here is a size chart:

https://www.discounthydraulichose.com/v/vspfiles/downloadables/thread_guide.pdf

Thanks very much, that site shows exactly what I have, looks like a standard part to me.

 

[JeffroL]

Just a quick update. I was able to replace the leaking hydraulic hoses and 7 others that looked very worn. Zero leaking fluid now. There were a couple however that were extremely hard to access. Hard to know how to squeeze a wrench into some places to break free a 30 year old fitting!! Any tips / tricks?

 

[GLyford]

I have heard of, and seen video of, people using a chisel on the corner of the flats to loosen or tighten fittings in tight spots, but have never done it myself. If you think about it, most hoses don't get taken apart and put back together a lot, they mostly get put on once and off once and tossed with the bad hose so a few chisel marks isn't likely to cause bigger issues down the line.

I tried finding the video again that shows it being done, but haven't had luck so far.

Your other option is taking a 2nd hand or import wrench and grinding off the outside enough that it can get at the fitting. It will be weaker, but how often do you have to change hoses? Grinding a new "fitting" wrench every few years is probably worth it to reduce frustration.

 

[Fallon]

I have heard of, and seen video of, people using a chisel on the corner of the flats to loosen or tighten fittings in tight spots, but have never done it myself. If you think about it, most hoses don't get taken apart and put back together a lot, they mostly get put on once and off once and tossed with the bad hose so a few chisel marks isn't likely to cause bigger issues down the line.

I tried finding the video again that shows it being done, but haven't had luck so far.

Your other option is taking a 2nd hand or import wrench and grinding off the outside enough that it can get at the fitting. It will be weaker, but how often do you have to change hoses? Grinding a new "fitting" wrench every few years is probably worth it to reduce frustration.

Had to do the chisle thing on a hydraulic filter on my new L4060 on the first change. No room to get any leverage on a strap wrench. It's ugly & kind of destroys the fitting(filter) in question, but often works.

 

[sailfast]

Frequently there are bent wrenches and tubing wrenches that might fit

 

[oldnslo]

Shoot..mistyped that. It is a backhoe not a tractor. I don't know if that makes a difference in the hydraulic pressure

Yes it could make a difference. I do not know what pressure Deere ran these at but suspect it was higher than 2500 PSI. Most hoses have some type of marking on them showing size and rating but being 20 + years old the markings could be gone. Older hoses it was molded in where newer hoses it is screen printed on.

 

[Xfaxman]

Just a quick update.------
There were a couple however that were extremely hard to access. Hard to know how to squeeze a wrench into some places to break free a 30 year old fitting!! Any tips / tricks?

Buy a set of Hydraulic Wrenches, same size at each end, but different angle:

 

[beowulf]

I had a similar problem - could not get a hose off. It was not because it was in an awkward place - just would not come off. It is discussed in this link here: http://www.tractorbynet.com/forums/parts-repairs/382939-help-hydraulic-hose-will-not.html

You can find suggestions there and here is a copy of what I posted as to what finally worked:
After trying everything else, the nut was fairly well rounded. Then I took a metal file and filed the nut flat on opposite sides and then tried different box wrenches to see which gave me the tightest fit at the two new flat edges. It happened to be a SAE wrench that fit the tightest - I tapped it on - a real tight fit on the nut. The wrench did grip the nut well enough but still no give. Then I took a short piece of pipe to slip over the end of the box wrench for leverage. And at the same time had my wife hold a heat gun to the female cylinder fitting. It still took a lot of torque but it finally broke loose and then easily came off by hand. I have no idea what the problem was - it almost seemed like it was in there so tight that it sort of "welded" itself - at the lip - to the cylinder. Anyway, happy tractor guy here, and off to town for a new hose.

 

[LouNY]

Lots of options between all the different open ended wrenchs, fitting wrenches, crowsfoot wrenches and when those don't work and it's a hose that I am replacing I have cut the line next to the fitting nut and used an impact socket and wrench which works good if accessible. Or old fashioned vise grips and then using a hammer on them.

 

[muddstopper]

Its always the hose in the middle of a line of hoses that has to come off. I usually just take different colored zip ties and mark all the hoses and then start taking them all off. Yea, I leak a little oil, but it usually beats standing on my head, and all the cussing that goes with it, trying to get to the hose that needs changing.

 

[Zebrafive]

Its always the hose in the middle of a line of hoses that has to come off. I usually just take different colored zip ties and mark all the hoses and then start taking them all off. Yea, I leak a little oil, but it usually beats standing on my head, and all the cussing that goes with it, trying to get to the hose that needs changing.

I have had to do the same on a three spool valve. Take off four to get to the one I need to fix. Colored ties can be your friend

 

[GLyford]

This is the chisel trick I was talking about

22 degrees and trying to fix my loader - YouTube

 

[powerscol]

Buy a set of Hydraulic Wrenches, same size at each end, but different angle:

View attachment 527043

There are also crow foot sockets that work with you ratchet wrench that work the same as above but inline with the hose. I got my two sets (Metric/English) from HF.

 

[Fallon]

There are also crow foot sockets that work with you ratchet wrench that work the same as above but inline with the hose. I got my two sets (Metric/English) from HF.

I'll 2nd that. Was glad I got & followed the same recommendation before my 3 spool & TnT install on my L3200. No if I could only figure out where I hid them last time I cleaned the shop...