Hydraulic hose fitting question
Printed From: Unofficial Allis
Category: Allis Chalmers
Forum Name: Construction and other equipment
Forum Description: everything else with orange (or yellow) paint
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=130515
Printed Date: 26 Jun 2024 at 2:49am
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com
Topic: Hydraulic hose fitting question
Posted By: EDWD45
Subject: Hydraulic hose fitting question
Date Posted: 27 Oct 2016 at 11:05am
|
I just replaced a hydraulic hose for one of the front bucket rams. I torqued them up good and tight, but still have a small but noticeable leak on one end. Can I use Teflon tape on the threads, or should I put an o-ring on the fitting? Thanks.
|
Replies:
Posted By: Dans 7080
Date Posted: 27 Oct 2016 at 11:41am
I'd depends it there o-ring fittings or not. If they are they should have an o-ring. If its pipe thread the tape will work.
-------------
When someone tells you Nothings Impossible, Tell them to slam a revolving door
|
Posted By: Eric B
Date Posted: 27 Oct 2016 at 1:05pm
I have used liquid thread sealer used for gas fitting (and any threads for plumbing) to be very successful. It is good up to 6000 PSI. I would smear a bit on the cone of the hose fitting...sparingly because you don't want any excess to travel through the hydraulics.
-------------
Currently- WD,WC,3WF's,2 D14's B. Previously- I 600,TL745,200,FL9,FR12,H3,816 LBH. Earth has no sorrow that Heaven cannot heal!
|
Posted By: Dozer
Date Posted: 27 Oct 2016 at 4:49pm
Some hose fittings have threads that fit together but are not meant to connect. Example NPT (taper) and NP (straight) The straight fitting is mated to a swivel fitting that seals on the inside diameter.
Do you have the correct fitting combination?
|
Posted By: DiyDave
Date Posted: 27 Oct 2016 at 6:01pm
|
What dozer said is right. Get the right fittings, and you won't have leaks. be careful, leaking hyd fittings can spray an almost invisible stream of high pressure hyd fluid, that can cut through, and inject itself into skin...
|
Posted By: Dan73
Date Posted: 27 Oct 2016 at 6:12pm
|
Dave is right and nothing sucks worse then a hot oil bath. Been there when a line blew. I got lucky I guess got a cut and burn on one arm when it blew on a skid steer. Actually the same model Les is working on. You is stuck in them when things go wrong no real jumping off.
|
Posted By: Coke-in-MN
Date Posted: 27 Oct 2016 at 8:39pm
|
Do not use TEFLON TAPE on hyd fittings - pipe dope , liquid teflon pipe dope, or such - the tape may work but will also migrate into pumps and cylinders and create problems . Most people do not apply the tape correctly as it needs to be spaced back 1 1/2 threads from the end of fitting so as to NOT migrate into flow (be it gas, fluid, or compressed air or gas.) For natural gas and propane a special tape is available also but is easier to use pipe dope.
-------------
Faith isn't a jump in the dark. It is a walk in the light. Faith is not guessing; it is knowing something.
"Challenges are what make life interesting; overcoming them is what makes life meaningful."
|
Posted By: DMiller
Date Posted: 28 Oct 2016 at 7:30am
Some SAE fittings will start and the nut tighten on JIC fittings which is what my tractor has. They will not seal as SAE is 45degree flare and JIC 37degree. Can realy screw up a fitting.
|
Posted By: CAL(KS)
Date Posted: 28 Oct 2016 at 7:39am
|
flare ends can also crack, very hard to see but still leak
-------------
Me -C,U,UC,WC,WD45,190XT,TL-12,145T,HD6G,HD16,HD20
Dad- WD, D17D, D19D, RT100A, 7020, 7080,7580, 2-8550's, 2-S77, HD15
|
Posted By: dustydoo
Date Posted: 28 Oct 2016 at 8:50pm
If they are flare fittings, and when tight still leak it may have a nick in one of the seats ! At most hydraulic repair shops they make an insert that is a tiny copper cup. It goes between the two fittings and will usually seal small leaks !
|
Posted By: EDWD45
Date Posted: 30 Oct 2016 at 1:43pm
Thanks to all that replied. The guy that made up the replacement hose said I had JIC fittings. The swivel end tightened up just fine with no leak, and the other end is where the leak developed. When I took the old hose off, there was an o-ring on the straight end, and the guy said that's not necessary with JIC fittings. Well, it's a 1982 model, and maybe back in those days an o-ring was appropriate (?).
Ed
|
Posted By: Dozer
Date Posted: 30 Oct 2016 at 2:16pm
|
"O" rings are not used with JIC fittings. The fact that there was one there says that the hydraulic joint was previously damaged. JIC's are metal to metal seal. Perhaps it was an SAE to JIC improper connection. As previously posted a copper washer can be used to seal a damaged connection. "O" rings are used in ORB and ORFS fittings.
|
|