Rebuilding FEL should I switch from NPT to JIC

[woolyAcres]

I've been working at getting the FEL on the (used) tractor I recently purchased in good working order. It's a 30-year old machine so I'm looking at a new loader valve and some new hoses. I'd like to add in some quick disconnects so removing the loader would be a possibility. Everything on the loader and hydraulics (including the supply hoses from the tractor to the loader valve) are NPT. From my reading on here it looks like folks prefer JIC. Is it worth trying to convert things? I'll end up with a mixed system because the fixed lines on my loader are 1/4" NPT and I don't intend to remove/replace those. In addition, the ports where the IN/OUT tie-in for the tractor's hydraulics are 3/8" NPT. Though I could replace those hoses (they don't need it) I can't replace the orifice on the tractor so it will always be NPT.

I'm leaning toward keeping everything NPT. If I switch what I can to JIC, I'll still have NPT in the system. My local tractor supply also has lines, fittings, etc in NPT so repairs might be easier.

Are there compelling reasons to convert those parts that I can to JIC?

Thanks

 

[denmarktwp]

Are there compelling reasons to convert those parts that I can to JIC?

Thanks

Yes there are. Both JIC and SAE/ORB fittings are far superior against leakage. They are designed for high pressure hydraulic systems. NPT works but not well. You can tighten JIC and SAE with normal wrenches. An NPT fitting requires a long handle and/or teflon tape. The tractor supply type stores mostly have NPT fittings. But places like Surplus Center and Discount Hydraulic Hose have all of JIC/SAE fittings you're likely to need. The fittings/hoses with be at your door in 2 or 3 days.

I'm installing a power beyond system to my JD 955 and recently went through this whole question. The only fittings that will be NPT will be the quick disconnects. But I'm going to put JIC to NPT adapters on them in order to minimize the amount of NPT leaks I'll have.

That's my experience.

 

[Silvic]

I would. It is worth the effort.

 

[stan33]

One thing to bear in mind is if the hose fittings you have are field replaceable or not. With that many hoses/fittings (I just did mine: 28 fittings) the cost of the fittings is considerable.
If you have field replaceable and they haven't been re-used already and there is heat generated from the fittings as they are put on new hoses, you can save yourself hundreds. If you go that route, get a hose supplier to fit them so you are sure they are ok to be re-used and are on right.

 

[woolyAcres]

Well I'll price it out both ways. My guess is price won't be that much different. What I'm more concerned about is the ability to repair something should it break, but this isn't a 'daily driver' and with a near total rebuild I hope that day is pretty far away so maybe the availability of NPT stuff locally isn't really a big help anyway.

Thanks for the input. I'll look into the JIC fittings.

 

[woolyAcres]

I'm installing a power beyond system to my JD 955 and recently went through this whole question. The only fittings that will be NPT will be the quick disconnects. But I'm going to put JIC to NPT adapters on them in order to minimize the amount of NPT leaks I'll have.

I too would like to add quick connect fittings so the loader can be removed. However I can't find the correct quick coupler in my size in anything but NPT. So it looks like I'd have to go from SAE to JIC then back to NPT for the coupler and back to JIC for the hose than back to NPT to connect to my cylinders. That doesn't seem right. Were you ever able to find either JIC quick couplers?

That back-and-fourth will almost certainly cost more and will have more opportunity for leaks with all the additional swapping to and fro. I'm still leaning toward everything NPT. If I could find the quick couplers in size 6 JIC at a reasonable price I'd reconsider.

 

[Zebrafive]

Sometimes you can find quick couplers with female ORB connection threads. You can add an O-ring to a male JIC hose end and thread the quick coupler on the hose. ORD and JIC are the same size threads for the same hose/tube size.

 

[sixdogs]

Interesting thread. I'd go with JIC.

 

[aczlan]

IMO, if you don't have many fittings and both ends of the hose need to end up as NPT, there is no good reason to switch to JIC.
In a fitting that gets taken off once in 15 or 20 years, as long as you use ptfe paste and get it good and tight (very doable with standard wrenches), it won't suddenly start to leak.
If your cylinders or valve were not NPT, I would say go ahead with a switch, but not if both ends are NPT.
If you have to convert back to NPT at both ends any, switching to JIC won't save you any leak points and will in fact increase your number of leak points.

Aaron Z

 

[muddstopper]

On a new build, I prefer to use JIC and SAE. With SAE Oring fittings, its pretty easy to line up your hoses to run the direction you want them to. Pipe thread fittings will seal only in one postion. If you loosen a pipe fitting and then retighten, it will point a different direction. Pipe threads are a tapered thread and each time you tighten the fittings, the threads deform. Overtighing can cause as many leaks as under tighting. With that said, I think if the equipment already was configured using pipe fittings, I would probably just stick with it. You said the loader is 30 years old, how many fittings have been changed in its life time. I bet very few, if any and them most likely because they got broke, which can be done to JIC and SAE.