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O-Ring Boss fitting troubles

hosspuller · 2020-04-29 19:08

I have a 45 degree O-Ring boss fitting that's leaking. The problem is: It's installed in a valve that is obstructed and prevents fitting removal without removing the valve. The valve is buried in the machine and is almost inaccessible. The fitting can be unscrewed about 3/4 of the thread before hitting the axle housing, so the washer and the O-ring is accessible but not changeable. Is there any solution or trick to the leak I'm missing ?

Replies23
  1. #1willie592020-04-29 19:23

    Without seeing the bigger picture, kinda hard to say you have other options, but it's looking like valve body removal.

  2. #2Cmark2020-04-29 19:25

    If removing the valve is out of the question a couple of things I can think of: Grind a pocket in the casting that it is hitting. Or Saw through the fitting to remove it then replace it with a straight nipple and remake the hose with a 45 or 90 degree end.

  3. #3excavator2020-04-29 19:51

    That is my thought. Turn the fitting so it's pointing up, put some hardening silicone in it, let it dry and cut through the fitting/silicone so that no metal goes inside.

  4. #4hosspuller2020-04-29 20:01

    Thanks for the ideas and attention. …. It's reassembled now, I'll get another pic to show the relative positions and spaces. Had a problem even getting a crowfoot flare nut wrench onto it.

  5. #5Truck Shop2020-04-29 20:42

    You sure what your working on isn't made by Feightliner, because their pros at piling **** on top of ****.

  6. #6Vetech632020-04-29 20:56

    Ok, you guys can rag on me after I make this comment/ suggestion. Unscrew it as far as you can and wrap Teflon tape around the oring. Believe it or not, it does work.

  7. #7hosspuller2020-04-29 21:21

    It's not an outrageous suggestion. I think it potentially doable. Especially if it doesn't work, I'm not stuck with a sawed off fitting. I think the problem is either a damaged O-ring or poor machining of the valve or fitting. By the pristine green paint, this problem left the Deere factory. Vetech, Since you've done this. In the photo, the fitting is out as far as the obstruction allows. Do you mean the actual O-ring or the threads of the fitting? If the threads, I expect the Teflon to wad up in the space intended for the O-ring. The washer and nut should compress it into a seal.

  8. #8willie592020-04-29 21:49

    ORB fitting seals fail for two reasons. 1) age, over time heat takes it tole on the o-ring, it no longer is elastic so it can't compress under pressure and make an effective seal and begins leaking, or 2) in the case of adjustable ORB fittings, which that fitting is, improper installation of the fitting. Some adjustable ORB fittings are "idiot proof", but most are not. If that fitting wasn't installed with the jam nut and washer in the proper position, that is, washer slid fully back on the fitting and jam nut seated against the washer. If instead the jam nut was not against the washer it will bend/deflect the washer on installation, recipe for failure, I've seen it on OEM installed fittings. Would teflon tape work? Don't know, never tried that on ORB fittings, but I wager if it did work you'd only be buying time.

  9. #9mg23612020-04-30 05:36

    A new o-ring "might" be able to stretch over the jam nut?? Worth a try.

  10. #10mg23612020-04-30 06:23

    As Jeff Foxworthy would say, "You know you're a redneck when....?

  11. #11Vetech632020-04-30 06:58

    Yeah pretty much. I have done this a couple of times in order to get by. The tape works great, but you have to wrap it in the right direction. In other words, wrap the tape lefty so the loose end doesn't wad up. I personally would just use maybe 2 wraps at the threads right to the oring. Hell, like Willie said, what have you got to lose?

  12. #12Ronsii2020-04-30 09:36

    You're not the only one it has worked for

  13. #13mitch5042020-04-30 10:46

    Amazing what works if you don't have sense enough to know it won't....

  14. #14hosspuller2020-04-30 15:09

    Here's the whole picture of the fitting location. Tight as a Frog's *** The lower 45 fitting is the leaker. Just noticed the jam nut is closer to the valve body than the other fitting. Machining tolerance part of my problem ? Will apply some Teflon tape to it. Wish me luck

  15. #15Nige2020-04-30 16:33

    See if mg2361's idea of stretching a new o-ring over the top of the jam nut works .......... obviously before you cut off the old one.

  16. #16Truck Shop2020-04-30 18:08

    And cover the fitting and o-ring with Syl Glyde before you try it. It will probably slip right over using a O-ring Pick real easy like.

  17. #17heymccall2020-04-30 18:47

    Looking those up close pictures, and guessing that that's an axle below, couldn't you just loosen the axle bolts and jack the frame away?

  18. #18hosspuller2020-04-30 19:21

    Thanks for the thought... It's a Deere 5065e There is no frame. Everything rests on the engine, trans and axles. The offending part houses the brakes, reduction gears, axle shaft, and God knows what else. Plus the ROPS and fuel tank sits on the housing. I think, a sharp stick in the eye would be preferable.

  19. #19hosspuller2020-04-30 19:43

    Tried to tighten the fitting (after backing the nut and washer) into position. It wouldn't meet the tube by a quarter turn, So had to back it off 3/4 turn. … The O-ring Teflon is wrapped and the fitting jam nut tightened. This week-end, I'm cutting hay. I'll report back in a few days. Thanks to all, for the support and Thoughts. ​

  20. #20Volvomad2020-05-02 17:22

    Simple solutions like tape always worth a shot provided it is carefully applied . If it fails (hope not ) heat the o ring before fishing it over the lock nut . You could round the nut edges a little if needed ,room permitting .

  21. #21Delmer2020-05-02 19:51

    Wrap the nut with electrical tape before you try to put a new o ring over the nut. Have a couple spare o rings, I bet you'll get one over, then you can cut the old one and go.

  22. #22willie592020-05-02 20:33

    O-ring boss fittings use 900 series o-rings and they're typically 90 durometer, would be tough to stretch one of those over the nut and washer of the fitting. You can get 900 series o-rings that are 70 durometer that are much more elastic, that's what I'd go with.

  23. #23hosspuller2020-05-05 19:15

    Success … Thanks Vetech63 and everyone that replied for the support and suggestions. Wrapping the O-ring with tape sealed the leak. Two wraps with 1/2 inch wide, thin (vs the thicker stuff) Teflon tape. Tucked the edges to the O-ring with a wood toothpick. Ran the tractor for 6 hours with a rag under the fitting. No oil spot to be seen. Compare the photos in posts #15 and #20. Likely a machining problem IMHO.