Ford 711 Loader (soundguy)

[Yudt06]

I have a hydraulic leak from the elbow located at the bottom of the hydraulic cylinder on my Ford 711 Loader. After disassembly it appears there was some type of a rubber O-Ring or Nylon Flat washer that has since worn away hence the leak. For my 711 Guys like Soundguy can anyone guide me to which type of seal I need to reinstall to seal the elbow threads into the cylinder ?

 

[Jim.ME]

From looking at the parts book it would appear the loader lift cylinder has a 3/8 pipe street elbow in the bottom cylinder port the hose hooks to. NPT (pipe) thread is tapered so it would use pipe dope or tape on it, not an O-ring or seal. If someone put a large amount of heavy pipe dope on the elbow in the past it might have rolled up, hardened, and look like a deteriorating O-ring or seal washer. This info might be wrong, just saying what it appears to have in the parts book.

 

[Sean in PA]

Is it where the elbow screws into the cylinder or where the line screws into the elbow? In either case, it does look like a street elbow which should be NPT and should only need pipe dope or tape. If it doesn't seal with either, then the threads could be worn, in which case a new elbow might be in order.

 

[Tom Bond]

Had the same issue with mine a few years back. Here's my thread from it. All I ended up doing was replacing the entire fitting with a steel fitting and some pipe tape and good to go.

https://forums.yesterdaystractors.com/viewtopic.php?t=1360385&highlight=

 

[Yudt06]

Thanks for all the advice guys. I think I?ll replace that elbow with some Teflon tape and call it a day

 

[Colin King]

As Tom, Sean, and Jim have said, it's just an elbow with NPT threads. R&R the elbow. Prior to installation, clean the threads and add some Teflon tape to any disassembled connections.

Colin

 

[sotxbill]

looks like the old fitting was an ORB fitting that uses an oring/brass washer to seal correctly.. where an npt fitting is a tapered fitting and due to the taper, it gets tighter the further you screw it in... an orb allows you to turn the fitting in any direction and then tighten down the lock nut to seal the oring.

these are not interchangeable as the orb is not taper threaded where the npt is... so the holes are cut different. Also an orb hole usually has a flat spot or even a groove at the the oring to seal against, where the npt does not. While an orb will... screw into the hole, it will be wobbly as it only catches a few of the tapered threads..

 

[Jim.ME]

(quoted from post at 11:58:52 01/06/20)

looks like the old fitting was an ORB fitting that uses an oring/brass washer to seal correctly.. where an npt fitting is a tapered fitting and due to the taper, it gets tighter the further you screw it in... an orb allows you to turn the fitting in any direction and then tighten down the lock nut to seal the oring.

these are not interchangeable as the orb is not taper threaded where the npt is... so the holes are cut different. Also an orb hole usually has a flat spot or even a groove at the the oring to seal against, where the npt does not. While an orb will... screw into the hole, it will be wobbly as it only catches a few of the tapered threads..

I have to respectfully disagree with you, as I have not seen an ORB fitting posted by Yudt06. The photo Tom Bond posted was a black iron, 150 PSI, NPT Street elbow with a jam nut and something for a synthetic seal under the jam nut. This was done on some applications to lock the elbow in a given orientation years ago prior to the ORB fittings. And they did leak if disturbed, which was not hard to do given the NPT tapered threads. An ORB fitting would be machined steel, rated for much more. pressure. JMHO.

 

[Yudt06]

Thanks for all the help guys. After close inspection it intact has that nut to tighten down one the valve is in its proper spot. I?ve ordered some new rubber washers to spec and will see if that will seal this elbow once tighten. I?ll keep everyone posted for future reference