Fitting ID

HALSJCB · Jun 20, 2019

Can anyone ID this fitting for me. It is attaching a hydraulic hose to the cylinder of my excavator thumb. There is a washer between the nut and the cylinder end cap that I think might have a o-ring sandwiched in there. That area appears to be the source of my leak. Not sure if it is a o-ring boss or o-ring face seal. Machine is under warranty yet so I don't want to just take it apart since I am not up on hydraulic fittings and their applications. Most likely a bad o-ring and an easy fix for one who knows and happens to have the parts at their disposal. Waiting for service tech to be scheduled to fix it.

BigWrench55 · Jun 20, 2019

Check to see if that fitting is loose. If so it will leak. Simply tighten the jam nut. If that doesn't help then the oring is bad. The threaded part into the cylinder is oring boss.

heymccall · Jun 20, 2019

It's either a BOSS/ ORB type or BSPP fitting into the cylinder. Since you couldn't tell us what machine and the location on the machine, we can't tell you the size or if it's SAE or British.

John C. · Jun 20, 2019

It is a bulkhead fitting on the cylinder side and a JIC male on the hose side. It is configured as a ninety degree elbow. Cylinder and parts look brand new. It's a wonder how that got out of the shop without someone test it prior to being shipped.

funwithfuel · Jun 20, 2019

It is JIC male by ORB male. On the hose it says FJX which would be gates female jic swivel. Please look at wrench flats of hose end for something like -4, -6 or something along those lines.

Dang, John beat me to the punch again!

92U 3406 · Jun 20, 2019

Looks like ORB. First thing I'd do is try and tighten the nut. If that fails, remove fitting and replace o-ring.

Personally I'd just fix it myself. Probably more of a hassle trying to get the dealer to come look at it. Less than a 5 minute fix with a couple wrenches, an o-ring and a litre or 2 of hydraulic oil.

mikebramel · Jun 20, 2019

Dont see re usable hose ends much

Does it take 11/16(906 oring) or 7/8(908) wrench 1" (910)

Make sure the oring is sitting in the groove of the fitting, not on the threads

kshansen · Jun 20, 2019

mikebramel said:
Dont see re usable hose ends much

Does it take 11/16(906 oring) or 7/8(908) wrench 1" (910)

Make sure the oring is sitting in the groove of the fitting, not on the threads

Yes can be a problem if someone failed to back off the nut all the way and push the washer back in the groove before installing the oring. Then screw in as far as possible by hand and only back out enough to have fitting pointing in the correct direction before running the nut down to compress the oring for a good seal.

heymccall · Jun 20, 2019

I only pointed out that if it were on a Caterpillar or Deere, I'd call it ORB. But, on a Yanmar, it would be BSPP, and on a Komatsu, it'd be a JIS thread.
If I use a ORB 12 ring on a Takeuchi 12 w/ BSPP, it will leak soon after. Same with Komatsu and Kobelco.

HALSJCB · Jun 20, 2019

I am located in New York State, USA and the machine is a JCB 8029 with less than 100 hours. The machine came plumbed for the auxillary circuit and the thumb was dealer installed. I checked the size of the nut behind the washer and it takes an 11/16 wrench. The hose side of the elbow thread measures 9/16 and I assume that it is a jic fitting ( # 6 ?). I did not disassemble the fitting to look for marks on the nut flats but did notice the fitting is marked China. Like what isn't these days.

I bought a new machine so I wouldn't have to spend a lot of time wrenching and the service manager offered to send a tech by so I accepted his offer. I have the parts book but the thumb assembly is not in it. No part # or schematics for a guide. I did try tightening the fitting but it did not seem loose and did not stop the leak.

Thanks for all the tips and help, I really appreciate it.

heymccall · Jun 20, 2019

If the thumb isn't from JCB, it is most likely ORB.

funwithfuel · Jun 20, 2019

I see what I think happened. The fitting appears to have impacted on the stick. The fitting may have been cracked as a result. When the guy comes to check it out, verify that the fitting cannot touch stick or you/they may have to rethink this.

kshansen · Jun 20, 2019

funwithfuel said:
I see what I think happened. The fitting appears to have impacted on the stick. The fitting may have been cracked as a result. When the guy comes to check it out, verify that the fitting cannot touch stick or you/they may have to rethink this.

Good eye FWF I had to go back and take a look! So I redid the picture with a lime green arrow pointing to the apparent impact point. Definitely does need to be checked close and addressed.

Tags · Jun 20, 2019

I actually think that mark is the edge of the weld where they painted it after welding not an impact mark, it looks like the paint is thin there and it's starting to rust....or maybe an impact mark, who am I to say either way....

heymccall · Jun 20, 2019

I see the jamb nut could be down too far, forcing the inner diameter of the O-ring to distort on the fitting threads.
Fitting should've been in another full turn before tightening nut.
BUT, it depends on the brand. Not all brands carry the same profile...this image allows you to see the usable range for the Oring on what I believe to be a Tompkins fitting.

HALSJCB · Jun 20, 2019

Yes Tags you are right about the mark being black paint that bled under the masking tape. The thumb bracket was welded to the stick and then painted black. The picture I posted shows both ends of the hose that is bent like a hairpin. When the thumb is operated to each end of its stroke the hose does flex and maybe that is causing the fitting to move just enough to start weeping. The thumb was manufactured by TAG and only just recently started to leak.

The tech is scheduled to visit tomorrow morning. I will make sure that it checks out with a full range of motion and that the nut is backed off fully to insure the threads and o-ring do not contact. I will report the results of the repair.

Theweldor · Jun 20, 2019

There is something to be said for the Dealer you bought the machine from. A lot of them would not offer to remedy your problem so easily. It should be a simple fix, it is excellent that they stand behind their work !!!

Oldcatpusher · Jun 20, 2019

Use a 90 durometer o ring on the jam nut. Others will work but not last

HALSJCB · Jun 21, 2019

Well the tech showed up this morning and repaired the leak. The fitting was fine but the o-ring was in bad shape. He replaced it with a new one and then he had me cycle the thumb fully open and closed a couple dozen times. NO LEAKS. The fitting looks just like the picture posted by heymccall. I did forget to ask him what the durometer rating was of the o-ring he installed. I guess it would behoove me to purchase an assortment o-ring kit to have on hand. Must be a lot more o-rings buried in the machine with all those hydraulic hoses and valves.
Liftech in Lancaster NY is where I bought the machine and theyhave been a pleasure to deal with. Glad that I stopped to check out the machine they had at the NY Farm Show.
Thanks again for all the suggestions and tips.

kshansen · Jun 21, 2019

HALSJCB said:
Well the tech showed up this morning and repaired the leak. The fitting was fine but the o-ring was in bad shape.

So it sounds like the person who installed it did not make sure the jam nut was backed off allowing the washer and oring to correctly position their-selves.

Having some spare orings on hand would not be a bad idea, just need to be sure they are the correct type for the application. Might want to see if the tech who was out there today could give you some advice on a good kit for your machine.

Fitting ID

Member

Senior Member

Senior Member

Senior Member

Senior Member

Senior Member

Senior Member

Senior Member

Senior Member

Member

Senior Member

Senior Member

Senior Member

Senior Member

Senior Member

Member

Senior Member

Well-Known Member

Member

Senior Member