I have a new Ron Davis aluminum radiator and I striped the upper transmission line threads. What should i do? I went to get a helicoil kit and the guy at the parts store made me question if I could fix it myself. He said pull the radiator and take it to a shop to get it fixed. Is a thread repair that big a job? I alos found the Timeserts but that kit is extremely pricey, I have to watch the $$$. I have also read and been told about problems with the helicoil coming out. Tell me how to fix this the right way.

Problem with the heli-coil is that it wouldn't be leak-proof. I'd either get it fixed at a repair shop, or forget it, leave it empty, and get an aftermarket tranny fluid cooler (whatever is cheaper).

tranny cooler is the best option its a hassle to fool with those thread repar kits

Unless it's pipe theaded, the threads aren't what seals it anyway. I'd get someone to weld a new bung on it.

The repair shop would be best but there is not one close and my work schedule will make it next to impossible to get there. I do eventually plan to run an external cooler but due to funds and how I wanted to install it I wasn't ready to do it that way yet. So with that said, is the Helicoil really a bad idea for this type repair? Thanks Mike

I would not take any chances with the transmission lines. Blow one of those and you will know it in a bad way.Sorry but the shop is really your only choice. By the way after market auxiliary coolers are just that. They are meant to be run with and after your main cooler. IMO

Did you try and re-tap it? Or is it too chewed up? Aluminum is very easy to tap, especially if you pull it off of the car. A helicoil would work if the fit is tight, I would use a small amount of epoxy between it and the radiator. You'll have to make sure that the fitting on the tranny line is still workable. Clean it up w/ a dye.
If you try the helicoil, once it is installed, make sure that you clip the little wire out of the bottom of it, so as not to restrict flow.

Thanks for the replies. The threads are completely gone. I am thinking that I will try the helicoil because today is the only day I have to fix it and my other car goes in the bodyshop Monday so I have to drive this thing. The threads on the transmission line appear good but I will clean them up to make sure.

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Ok, so I am trying to tap new threads and now another problem. At the back of the opening in the radiator for the transmission line, the rim that the flare on the line seats against wont let the tap go in far enough to start threading. Should I just drill it out? I am really going to have a hard time getting this thing to a shop to get it repaired, which is why I wanted to do this myself. What do I do now?

you cant drill that rim out, thats what the flare seats on and seals to. The threads dont seal in that application, they are straight threads.

if the threads are destroyed, what are you trying to re thread?

you need to have the bung removed and a new one installed. No real other way to do it, sorry

He's right don;t drill the seat out. I have helicoiled these before, I had to cut the the tip of the tap off so that it could cut threads, otherwise you will need a new bung welded on.

J91 if you don't mind help me understand the helicoil. If I were to put a fitting into the radiator that would allow me to run a hose to an inline tranny cooler and the fitting threads are 1/2" 20 fine thread, what size tap and helicoil do I need? The guy at the parts store didn't seem to have the right answer even though I showed him the fitting that I would be using. Also did you cut your tap just at the point where it tappers and will a dremel do the job? This thread repair stuff just confusses me. Im going to try to get this done myself since my only other option is finding a shop anyway. Thanks

You should get a helicoil the same size of your tranny line. I do not know the numerical value off the top of my head. It will come w/proper tap (oversized to accept the coil) , then tap it, screw in the helicoil, clip the little wire off and screw the line in. If you use a fitting you may have to drill to big of a whole?
I did cut the tap off just past the taper point, and a dremel should do the job, email me a pic @ jtsg91@gmail.com if you can, and let me see the damage include this fitting in photos.....

I accept with information:The repair shop would be best but there is not one close and my work schedule will make it next to impossible to get there.