Gear to cooler hose teflon O ring

Windstar 2000 300,000 miles. Gear to cooler line is leaking at the steering rack gear junction nut. there is no Teflon O-ring. The aluminum line is movable side to side. many YouTube videos show changing the Teflon O-ring stops leak. I am surprised how does this Teflon O-ring works. theoretically It should not let tight connection between the gear and the pipe. Are there other O-rings or washers in the nut or gear side??

Are you referring to the transmission fluid cooling lines from the transmission to the radiator?


If so, I had one that was leaking on my '96. These are 'quick connect' lines, and I found that it needed to be pushed in very firmly to make the connection 'snap' in, to insure a solid connection.

Thanks It is not transmission line but steering gear to cooler return line.

OK, then I think you talking about the power steering return lines which pass through a cooling loop that is attached under the radiator.

I've had the power steering rack disconnected from the pump on my '96 when the engine and transmission were out, but I don't remember that it was a connection like you're describing. However, I recently worked on a friends later (than '96) Ford Excursion that was leaking at one of the power steering pump connections, which was like the one you're describing. This was about nine months ago and I don't recall the details. I believe the one we took off was so worn that the fitting/nut came off of the end of the pipe. This is a type of hydraulic swivel fitting, and an O-ring is required to make the internal seal. There was another plastic o-ring on the outside of fitting.

Thanks. From the PS pump High pressure line comes out, goes to steering rack. There is sensor on this line. Years ago the same white Teflon washer on this high pressure line was damaged and so it was leaking. I had to buy it at that time for 200 USD + mechanic. Now The leak is form the from the steering rack and the lower return hose. This is low pressure return hose goes to cooler front of the AC condenser and then to PS fluid reservoir. There are a lot of videos about this white Teflon O ring. I want to know what is the magic in this white ring. It should not allow the full metal to metal contact of flared aluminum pipe and the gear. I have ordered again for 200 USD. I want to know only the mechanism how it works? What is the magic in it?

I don't remember what is in the connection, but I think it must have an O-ring, either rubber or plastic, to make the seal. It can't have a normal flare making the seal or the pipe wouldn't be able to turn.

You might be able to find something on-line with a search. There are a lot of different types of rotating hydraulic joints.

There are a few different designs of this concept. The captured nut has a smooth bore and the tubing has deformed "humps" that retain the nut and nylon seal. Unless there is good alignment, there may be metal to metal contact. The life of the connection can be extended by securing the tubes/hoses near the fitting so that there is little continuing swivel movement. Usually some tie-wraps will suffice.

Thanks. for explaining. but now it is more complicated how the nylon ring will maintain alignment of the tube inside?? Please be kind to explain more how to do tie wrap?

As the seal is compressed, it assumes more of an elongated spool shape. This provides a bit of alignment.

The engine can move about quite a bit inside the engine box area, especially if the driver is heavy footed and especially if the engine/tranny mounts are worn. This movement can be felt in the power steering hose assemblies. Using tie-wraps, one can minimize the hose movement at the rack area.

Thanks, for explaining nicely. Please! Let me know how to tie wrap?

Sometimes referred to as Zip-Ties:
.
https://www.homedepot.com/p/K-Tool-International-36-in-175-lb-Natural-Wire-Tie-25-Pack-KTI76360/207032809?source=shoppingads&locale=en-US&mtc=Shopping-B-F_Brand-G-Multi-NA-Multi-NA-Feed-PLA-NA-NA-Catchall_PLA&cm_mmc=Shopping-B-F_Brand-G-Multi-NA-Multi-NA-Feed-PLA-NA-NA-Catchall_PLA-71700000014585962-58700001236285396-92700010802552517&gclid=Cj0KCQiAmfmABhCHARIsACwPRADcRcslLHREQz_MiyKC VF0Zd6oqxBKevbXNYT5WR1JlTPz3wlvjKXoaAliZEALw_wcB&gclsrc=aw.ds

Thanks. Now I knew the magic of the Teflon seal. I bought the original Ford Motorcraft gear to cooler nose part No. XF2Z3A713AB from eBay. The magic is not the outer seal but an internal cylindrical Teflon seal which is between the inside the union nut and outer to the metal pipe.

with 300,000 miles; great maintenance.. but it might just be the nylon seal/o-ring, and not the hose.. those are only a few USD, not 200..
i think dorman and napa and the motormite/help! line carry these as an assortment pack; but they are the same for like 1995 to 2005 aerostar and windstar.. dorman# 82540? and HELP!#601-1364?..
and i think the flare nut size is an 18mm or a 3/4" with some electrical tape wrapped on the 'torque' side of the ear of the wrench; and a crowfoot open end on an extension and ratchet is best..
even though low pressure side, you could still use some vaseline jelly, or automotive wheel bearing grease to help hold, lock, and roll the o-ring into place..

Thanks. now I have got a new hose. In a few days I will install. The old one excessively moves inside the nut. Leak is between the nut and the metallic pipe. I can see the cylindrical seal inside the nut. So no side to side movement of the pipe relative to the nut, but nut can rotate around the pipe but still it air tight.