I replaced repaired radiator into 1998 C280. Tightened upper Transmission line Banjo Bolt with no issues. No leaking under pressure. Since the line going into the lower radiator transmission cooler port is a flared fitting, I've tightened it up as tight as it can go, but I'm still experiencing a tiny drip, when she's under pressure. Is there a trick to tightening it to prevent a leakage?
Lower transmission line leak at radiator bolt: trick to tighten and seal?
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I'd say to make sure to get the mating surfaces as clean as possible. Just a question, does all the transmission fluid come pouring out if the lines are disconnected (car turned off), or is there only minimal fluid loss (whatever happens to be in the lines)?
Patman1, I am so very sorry that I didn't revisit this thread. A year, plus, is inexcusable, and I apologize, but I still could use the help. I didn't receive a notification that a reply had been posted.
When I disconnect the lower transmission hose from the radiator connection, a small amount comes out. (I work on a slight incline in my driveway, and go down where the radiator shroud would be. I remove the shroud to work on that line.) I'd estimate it to be a couple of cups, 6 - 8 oz.
My solution, in Sept 2017, was to slather the back of the fitting/collar-nut, and the metal of the hose with Black Ultra RTF sealant. It created a seal from where the drip was occurring. It stopped the leak for about a year.
I noticed the drip occurring again, last week (Dec 2018). I removed the shroud, cleaned old Black Ultra RTF sealant off the fitting, and loosened the fitting/collar-nut. I pulled off the nut/collar, and waited for as much ATF to drain out as I could. It looked like some of the end of the radiator fitting was crushed, like a cross-threading had occurred. I was told, once to put on Teflon Tape, as used in plumbing applications to help seal it. I tried to apply the tape, but had difficulties, yet ended up with at least one wrapping of it along the radiator connection. I reattached the nut/collar, paying attention to how 'direct/straight' the fitting was. I tightened it as tight as I could, and again, slathered the nut/collar end-closest-to-the-transmission with the Black Ultra RTF. It has, still, a small drip, but not massive, and I don't see it on my driveway, yet, but have seen some along the bottom rubber radiator hose.
Is there supposed to be a rubber seal/o-ring at the back of that nut/collar to help seal that?
Thank you for your help, Patman1.
When I disconnect the lower transmission hose from the radiator connection, a small amount comes out. (I work on a slight incline in my driveway, and go down where the radiator shroud would be. I remove the shroud to work on that line.) I'd estimate it to be a couple of cups, 6 - 8 oz.
My solution, in Sept 2017, was to slather the back of the fitting/collar-nut, and the metal of the hose with Black Ultra RTF sealant. It created a seal from where the drip was occurring. It stopped the leak for about a year.
I noticed the drip occurring again, last week (Dec 2018). I removed the shroud, cleaned old Black Ultra RTF sealant off the fitting, and loosened the fitting/collar-nut. I pulled off the nut/collar, and waited for as much ATF to drain out as I could. It looked like some of the end of the radiator fitting was crushed, like a cross-threading had occurred. I was told, once to put on Teflon Tape, as used in plumbing applications to help seal it. I tried to apply the tape, but had difficulties, yet ended up with at least one wrapping of it along the radiator connection. I reattached the nut/collar, paying attention to how 'direct/straight' the fitting was. I tightened it as tight as I could, and again, slathered the nut/collar end-closest-to-the-transmission with the Black Ultra RTF. It has, still, a small drip, but not massive, and I don't see it on my driveway, yet, but have seen some along the bottom rubber radiator hose.
Is there supposed to be a rubber seal/o-ring at the back of that nut/collar to help seal that?
Thank you for your help, Patman1.
I haven't done this job on my car thankfully but I'm sure putting in some kind of O-Ring/gasket where you mentioned couldn't hurt. As for the teflon tape, I have no idea whether you applied it to a male or female fitting. Female fitting would be next to impossible to apply it to. An old plumbers trick to help put on teflon tape in tight spaces is to wrap some around the end of a pen or pencil as opposed to fiddling an entire roll around a small thread with little space to work with. I wouldn't worry about a tiny amount of teflon tape overlapping the first thread on your application and contaminating your fluid.
I would check my WIS to see if that part has an O-Ring but unfortunately the servers for most of the WIS programs out there no longer run or the software gets corrupted. (Don't waste your money on a WIS program.)
I think it would be much easier to use good quality teflon tape (Blue Monster Tape) and really try to get a good tightly wound five complete wraps (in a clockwise direction) on the thread before putting everything back together. Teflon tape is very weird if you don't use enough of it. I recently changed a water heater in my house and had a problem with one of the connections leaking. I did 4 wraps of it and water was still dripping from the threads. I took everything apart, did 6 wraps instead and not a single drop of water. I added plumbers pipe sealant on top of the teflon tape too (it can't hurt.)
If I was in your situation, I would be so mad that I'd even consider JB welding the f***er together and hope I never have a problem with the radiator again.
I would check my WIS to see if that part has an O-Ring but unfortunately the servers for most of the WIS programs out there no longer run or the software gets corrupted. (Don't waste your money on a WIS program.)
I think it would be much easier to use good quality teflon tape (Blue Monster Tape) and really try to get a good tightly wound five complete wraps (in a clockwise direction) on the thread before putting everything back together. Teflon tape is very weird if you don't use enough of it. I recently changed a water heater in my house and had a problem with one of the connections leaking. I did 4 wraps of it and water was still dripping from the threads. I took everything apart, did 6 wraps instead and not a single drop of water. I added plumbers pipe sealant on top of the teflon tape too (it can't hurt.)
If I was in your situation, I would be so mad that I'd even consider JB welding the f***er together and hope I never have a problem with the radiator again.
I put the teflon tape on the male extension from the radiator. I don't believe that there is an O-ring on the inside of the nut. It's like a brake line compression fitting, but the transmission line which 'mates' to that male extension is pressed onto the mating surface of the threaded radiator piece that sticks out from the radiator. I've not been under the C280 since the repair, and I've not seen any drips on driveway since I've done it. Thanks for your advice on the teflon tape. I'll check it out, further, though.
I was told one time by a company that makes stainless steel brake line kits, that the trick to getting them to seal is to tighten it up, loosen it, tighten it again, back and forth, until the end forms itself to the fitting. This transmission line I think would be very similar, and it would be worth a try. But it sounds like you have it sealed for the moment, so my advice would be don't fix what isn't broke.
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Im having an issue regarding the nut from the atf line to the radiator as well. My only problem is that the male connector and or the bolt(thought i believe it to be the male connector as i tested the bolt on my old radiator and it fit well) the male connection is indeed stripped and im struggling to find the correct size for a die kit. So far ive struck out twice on amazon trying to get the correct size. Anyone know the specs of this that might help me out a ton.
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Necropost.
You're best to start a new thread of your own vs. reviving the dead.
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