Hydraulic Fittings

[_M_]

Hello fellows,

I feel a bit silly asking this, but I'm wondering what the proper method for measuring threaded hydraulic fittings is. I need to replace the input hose on my 448 backhoe and plan to order it from Discount Hydraulics. I want to make sure I'm giving them the correct dimensions for the fittings I need crimped on. The Deere part # for the hose with fittings is M121861, but they don't give the size of the fittings. My best measurements show that the male end is 13/16" with 14 pitch threads and the female end is 3/4" with 16 pitch threads. The female side is definitely smaller than the male. I'm not sure whether to measure to the valley of the threads or the peak (hope my terminology makes sense here) or whatever is correct.

Meanwhile, the lady of the hour sits in the woods looking rather pathetic and lonely. I had to drop her off the tractor in an awkward position. When the hose blew, she was about to pop out a nice oak stump that was intended to crown the Thanksgiving burn pile. Let's get her back to work.

Thanks for the help.

 

[kennyd]

You will first need to determine the type of fittings they are, like NPT, JIC, ORB ect.

Then you can look at THIS chart on DHH's page to determine the size. You can also look at the different styles on THIS page to help identify the type you have.

 

[_M_]

Thanks for the links. From what I can tell, the male end is an NPSM fitting. I measured it with a caliper and according to the DHH chart it's a 1/2" fitting. The female end looks like a JIC fitting. I also measured it with a caliper and according to the DHH chart it is also 1/2". I've posted a couple pictures. Is anyone able to confirm the fitting types from the pictures?

 

[Spudland_Dave]

Just a tip....
What I did back a while ago was to buy a wide assortement of Male & Female Caps in various sizes & type...JIC/NPT/O-Ring/BSP/Etc:

And engraved the Size/Type on it (example JIC-4)...whenever I'm in doubt, I go to my special box and test em out...it hasnt failed me yet...Not to mention, you can bring the caps to your local friendly hose shop and get what you need without any hassle...

 

[kennyd]

Thanks for the links. From what I can tell, the male end is an NPSM fitting. I measured it with a caliper and according to the DHH chart it's a 1/2" fitting. The female end looks like a JIC fitting. I also measured it with a caliper and according to the DHH chart it is also 1/2". I've posted a couple pictures. Is anyone able to confirm the fitting types from the pictures?

I agree...

 

[kennyd]

Just a tip....
What I did back a while ago was to buy a wide assortement of Male & Female Caps in various sizes & type...JIC/NPT/O-Ring/BSP/Etc:

And engraved the Size/Type on it (example JIC-4)...whenever I'm in doubt, I go to my special box and test em out...it hasnt failed me yet...Not to mention, you can bring the caps to your local friendly hose shop and get what you need without any hassle...

Great idea!

 

[Wayne County Hose]

Just a hint, JIC and O-ring thread are the same thread. They will screw into each other.

 

[_M_]

Thank you for the tips and suggestions. DHH was able to confirm the types based on OD / ID measurements (using a caliper), the thread pitch, and the photos. Apparently the thread pitch is somewhat specific to the various fittings. For future reference for anyone else wanting to get this 448 hose assembly from DHH, the male fitting is part# MP-08-08 and the female fitting is part# FJX-08-08. I ended up going with hose part# KT-08 which is called Tough Cover (2 wire) hose with a working load of 5000psi for 1/2" hose. Hopefully it will wear better than the OEM hose (this is my second time replacing this hose). The tough cover hose also claims to have half the min. bend radius (3.5") as their standard 2 wire 1/2" hose (7"). Again, thank you for the help and advice. I now feel less silly about having asked for help as the world of fittings is far more complicated than I originally thought.

 

[Wayne County Hose]

Thank you for the tips and suggestions. DHH was able to confirm the types based on OD / ID measurements (using a caliper), the thread pitch, and the photos. Apparently the thread pitch is somewhat specific to the various fittings. For future reference for anyone else wanting to get this 448 hose assembly from DHH, the male fitting is part# MP-08-08 and the female fitting is part# FJX-08-08. I ended up going with hose part# KT-08 which is called Tough Cover (2 wire) hose with a working load of 5000psi for 1/2" hose. Hopefully it will wear better than the OEM hose (this is my second time replacing this hose). The tough cover hose also claims to have half the min. bend radius (3.5") as their standard 2 wire 1/2" hose (7"). Again, thank you for the help and advice. I now feel less silly about having asked for help as the world of fittings is far more complicated than I originally thought.

Well, I guess I just learned something. That's one heck of a hose. If you have problems with abrasion, I would put the plastic guard on it too. BTW, there is nothing special about the thread pitch, standard off the shelf fittings.