Hydraulic Leak

[gtater]

I just got a 5500 Mahindra 4wd, love the tractor, it's like a bulldozer. I have noticed a hydro leak on what I believe is the return line for the loader(it goes in where the drain plug for the hydro fluid is supposed to be). I have tried to tighten both fittings, put new teflon tape and liquid teflon on and no luck. It leaks a small amount just while sitting, but when it warms up it increases. Anyone else had this problem or any ideas on how to fix it? Also I am going to have to add fluid, my dealer said in the 5500 they are now using Hytran in both the Hydro and transmission, anyone else heard this? He said his mechanics just went to school and said they are telling everyone when they change the fluid to do this.

 

[MadReferee]

I just got a 5500 Mahindra 4wd, love the tractor, it's like a bulldozer. I have noticed a hydro leak on what I believe is the return line for the loader(it goes in where the drain plug for the hydro fluid is supposed to be). I have tried to tighten both fittings, put new teflon tape and liquid teflon on and no luck. It leaks a small amount just while sitting, but when it warms up it increases. Anyone else had this problem or any ideas on how to fix it? Also I am going to have to add fluid, my dealer said in the 5500 they are now using Hytran in both the Hydro and transmission, anyone else heard this? He said his mechanics just went to school and said they are telling everyone when they change the fluid to do this.

Don't use teflon tape. You don't want pieces of that getting into your hydraulic system. If the fitting is a JIC it seals on the cone and the cone may be deformed or not sealing properly. If the threads are NPT you may have issues with the tapers not quite matching. Try a fitting adapter. It will eliminate the hose or the threads in the tank.

 

[gtater]

Don't use teflon tape. You don't want pieces of that getting into your hydraulic system. If the fitting is a JIC it seals on the cone and the cone may be deformed or not sealing properly. If the threads are NPT you may have issues with the tapers not quite matching. Try a fitting adapter. It will eliminate the hose or the threads in the tank.

Excuse my ignorance but what is JIC and NPT? All of the hydro connections on my tractor have teflon tape on them from the factory so I assumed I was supposed to use it also. The fitting going into the drain plug appears to be straight. The other two are tapered if this helps.

 

[SPYDERLK]

Excuse my ignorance but what is JIC and NPT? All of the hydro connections on my tractor have teflon tape on them from the factory so I assumed I was supposed to use it also. The fitting going into the drain plug appears to be straight. The other two are tapered if this helps.

gtater, NPT is a taper thread exactly like that used on water pipe. Hydraulics use the same threadform but the fittings are much thicker walled and are quality steel. Teflon tape is great with these fittings, BUT, without proper and meticulous use, can get into your oil as Mad says. The problem is that the tape, applied to the male thread, is squeezed as the taper tightens. The teflon flows both directions - inward and outward. The trick is to leave the 1st 1-1/2 to two threads bare and wrap the tape only 2 turns around the fitting. - Only a double layer. - Wrap clockwise as viewed from the end. Due to the gap fill and lubricative properties of the teflon the fittings will not have to be cranked super tight.
This assembly process is pretty safe, BUT when you remove the fitting there is another problem. Teflon remains in the female thread and must be cleaned out before reassembly. A stiff toothbrush works well.
JIC fittings have 2 mating tapers forced together by a nut to form a metal to metal seal. These are nice! Chances are you will run into both NPT and JIC on your tractor. surpluscenter.com has good descriptive info.
larry