Transmission flare fitting at radiator

[new2yukon]

I was reading the shop manual earlier trying to help someone and came across a page that mentioned making sure that fitting was screwed all the way in and flush or it would leak. There were drawings of how it should and should not look like but I was and am now too tired to comprehend, time to hit the rack soon and my eyes are hurtin' real good.

I reinstalled it. Cleaned all threads with brake cleaner. Liberal liquid Teflon on threads. Will allow cure 24hrs.

Will try it tomorrow and respond with results.

I dont like sealing things this way but I'm sure lots of crazy things are done that we never know of.

Thank u all very much for your support and thoughts.

Stay tuned.

 

[jcb2]

I reinstalled it. Cleaned all threads with brake cleaner. Liberal liquid Teflon on threads. Will allow cure 24hrs.

Will try it tomorrow and respond with results.

I dont like sealing things this way but I'm sure lots of crazy things are done that we never know of.

Thank u all very much for your support and thoughts.

Stay tuned.

From the photo of the old fitting, it looks like it has “ISO” threads which are straight, not tapered like piping threads. They are not meant to be the seal but rather to push a gasket of sorts like an o-ring or soft plastic washer against the seat in the radiator. In fact, your photo appears to show a yellow plastic washer on the end of the connector fitting. Any pipe “dope” or sealant on the threads will likely not help for long.

My advice is to take it apart, clean everything again, make sure there is a seal washer of sorts between the end of the fitting and the seat inside the radiator then install it snuggly with some thread locker on the threads. Next connect the tubing to the fitting by inserting and using the clip per the instructions.

If you really think you need to add some type of paste sealant, use it very sparingly and only on the seal washer face(s). But honestly, I don’t think the design requires it. Good luck, buddy!

 

[jcb2]

From the photo of the old fitting, it looks like it has “ISO” threads which are straight, not tapered like piping threads. They are not meant to be the seal but rather to push a gasket of sorts like an o-ring or soft plastic washer against the seat in the radiator. In fact, your photo appears to show a yellow plastic washer on the end of the connector fitting. Any pipe “dope” or sealant on the threads will likely not help for long.

My advice is to take it apart, clean everything again, make sure there is a seal washer of sorts between the end of the fitting and the seat inside the radiator then install it snuggly with some thread locker on the threads. Next connect the tubing to the fitting by inserting and using the clip per the instructions.

If you really think you need to add some type of paste sealant, use it very sparingly and only on the seal washer face(s). But honestly, I don’t think the design requires it. Good luck, buddy!

OK. I just looked at the photo again and it’s hard to tell but it could be a flare connection. Was the old fitting flared at the end? Is what I thought to be a “seal washer” really the flare end? If that’s the case, no sealant is required there either because the seal is just the metal to metal contact area and the straight threads hold them tightly together.

If originally the fitting was one that just slid in place on a tube with a flared end, then you shouldn’t change it to a quick connect type unless it’s specifically made to use in a flared seat.

 

[new2yukon]

JCB2, I'm with ya. I agree about the threads.

However, there is no o-ring on the new fittings or the old one. They are purely meant to seal via flare fitting.

My liquid teflon did seal it up. Atleast for now, and I hope for a very long time. Who knows, maybe the teflon lube allowed it to tighten up more and it is actually sealing correctly. I snugged it up for sure, but never had an issue w/ fuel filter replacement sealing up at less torque.

I will keep watching and if issues then the rad will go back to mfgr under warranty or I will eat the cost. Either way, if it leaks I will prob buy acdelco that comes w/ the fittings installed.

If there is an alternative fitting that will work w/ my rad I am open to that, but threads would have to match and I wonder if one is available. I have seen similar fittings, but probably for slightly diff design.

 

[new2yukon]

Old fittings....new ones I had to install are exactly like them.

 

[new2yukon]

Update:

The teflon is holding so far. Have prob 2-3hrs run time on it and no leaks. One tranny line is sealed w/out any sealer and the other has the teflon on it. Both are ok.

Also, I did come across an expensive sealer made for minor flare imperfections, made by Henkel. In case somebody really needed help on a joint seal, this adhesive may just be a life saver.

Just an fyi.


https://www.henkel-adhesives.com/us/en/product/structural-adhesives/loctite_5452.html

 

[shuj]

g

 

[trailblazer]

Interesting that they made a sealer for connections that sealants are not supposed to be used with.

 

[new2yukon]

Interesting that they made a sealer for connections that sealants are not supposed to be used with.

Same thought as me, but the link I posted to was referenced from another site talking on hydraulics so it must be a "thing". The one referenced is very high-end and appears for very high pressure and for sealing surface imperfections.

It is strange though, for sure.

 

[wjburken]

Same thought as me, but the link I posted to was referenced from another site talking on hydraulics so it must be a "thing". The one referenced is very high-end and appears for very high pressure and for sealing surface imperfections.

It is strange though, for sure.

Not so strange really. In many hydraulic applications like on vehicle mounted equipment, it’s not uncommon for a hose fitting to get scratches in them when they get disconnected during service work. They bang on the floor or pavement and can get scratched or dinged up.