The passanger side of my radiator has an upper and lower transmission fluid line (I guess sending fluid to and from the radiator to cool off). The lines are tight, but fluid is leaking at the connection to the radiator. Any thoughts on how to stop the leaks? Are these lines under pressure? Thanks!

This connection uses a flare to seal, thus you might try tightening another 1/8th of a turn, or remove them and check to make sure the flare isn't damaged and makes a good seal.

Thanks, Brian. Is the line pressurized? If I unscrew the lines to check the flare, will lots of fluid drain? I don't think I will get anouther 1/8 turn. It is tight as can be. My thought was perhaps to use some type of thread lock? D

Answers to your questions:
Is the line pressurized? No, only with the engine running.

If I unscrew the lines to check the flare, will lots of fluid drain? No, if engine is not running. However, there will be some fluid. Place a drain pan underneath to catch fluid.

I don't think I will get another 1/8 turn. It is tight as can be. My thought was perhaps to use some type of thread lock? You can, but first, I'd go to the local hydraulics/pnuematic vendor or a fastener vendor and get a couple copper sealing washers for flares, probably a #10 or #12 flat. Try one in the loose line on the radiator. The sealing washer fits between the rad flare and the tubing flare. As the flare nut is tighten, the copper washer crushes, and forms a tight seal between the two flares.

The other attempt is to remove the leaking line, spray both mating ends with Brakleen, and get a tube of "LeakLock," from the A/C vendor, and apply a small diameter bead to the backside of the tubing flare and to the threads of the flare nut. Tighten snugly.

Always use to tubing wrench for the flare nut.

I had that pesky leak on my top tranny cooler connection. No matter how tight it was, it still weeped. A buddy mechanic showed me a trick that worked and it was so easy, Dab a SMALL (tiny) amount of axle grease on the end of the fitting, on the tubes bevel where it meets the radiator part, and then tighten. The grease helps the metals meet up and presto it stopped my leak after a year of fussing with it. smile.gif

Thank you for all of your input. I now have some things to try. D