Small leak: JB Weld, RTV Silicon, QuickSteel, All-Metal?

[termiflyer]

Hi all. I'm not sure if this is the best place to post, but I thought you might be most knowledgeable on this type of thing.

I've got a pinhole leak in an automatic transmission fluid cooling line. I'm hoping to avoid replacing the lines since they wind all over from in front of the radiator all the way back to the tranny. I would also like to avoid cutting a section out of the line, since the spot where the leak is is in the worst possbile spot to get at.

So, I'm hoping something like JB Weld will do the trick. I did a bit of looking around, and JB weld, RTV silicone sealant, quicksteel, all-metal all came up.

As you might expect, I am wondering if you can recommend a solution out of these, or anything else that I didn't mention.

Thanks in advance.

[curtis73]

None of these will be a good permanent fix. The JBweld will do OK, but be sure to completely clean and scuff the surfaces. The problem is that it has a good adhesion to metal, but not a consistent seal. It sticks well, but not in all areas. Often times it will still seep from around the patch.

This is going to sound very pathetic, but I've repaired them with 3/8" fuel line. The fuel line is fairly resistant to deterioration from the oil, and since the cooling lines only run about 20 psi at most, they will take the pressure.

Using a tubing cutter, just cut 1/2" section of the hard line out where the leak is, and replace it with a 3" section of hose with two clamps. To extend its life, take a little dowel, piece of steel, or something to "splint" the patch to prevent movement of the rubber.

You can use a hacksaw to cut it, but after you cut... remove that line at the tranny and the radiator and blow the fluid out. The metal shavings you just put in the fluid coudl easily destroy the tranny.

The nice thing is, if it starts leaking again after a year or two, its a 36-cent fix.

[bjdm151]

Yes,

I would suggest going for a fix like that rather than some sort of rtv or jb weld. In my experience you're going to either have to replace the hose, or do a simple fix like Curtis suggested.

[Austin8214]

I agree with Curtis as well. The other thing you could try is to bandaid it. By that a mean takeing a small thin pice of rubber gasket material and placing that over the pin hole. then secure the gasket with a small hose clamp. I think that should work for you if you absolutely do not want to cut the line.

[Kurtdg19]

I don't know if this would be exactly on the topic, but I've stopped leaks with RTV sealant on a cracked oil pan. The pain in the ass part was the fact that the crack happened at the threads. I had to cut out a small piece of sheetmetal, cut out a snug hold for the nut, put the nut in, and went liberal with the sealant. Much to my suprise, it worked great! I allowed the sealant to cure, refilled the oil, gave it a test, and no drips. Even during very hot summer days, there were no leaks of anykind. Of coarse the sealant is only a temporarily fix-it, but my other choice was to spend $70 dollars on a new pan, and lift the motor out to replace it. Needless to say I didn't want to pursue that path at that particular moment. $3.00 sealant worked (btw it was the black type). As of now I have a new pan, but the temorarily fix it worked well.

If you wanna give it a go, I'd say try it. If it doesn't work then your not out much, and you can always pursue a different path. Just make sure the metal around the crack is clean, and make sure you allow the sealant to cure before running your car.

Note: Be cautious for any air pockets that may form in the sealant. If so the fluid will find it and more and likely result in a failed attempt.

[benchtest]

termiflyer, You didn't mention WHY there is a pin hole leak. Steel lines aren't known for suddenly having pin holes. If it's cracked, Curtis' suggestions will likely patch it, but you need to find the cause and prevent it from happening again. If the line has rusted through, you can patch it, but it will likely find the next weak spot very quickly. Something to consider is all....

[termiflyer]

My only guess on cause is RUST. Given that, I may may have more problems impending, but getting it through the winter is my main objective for now (it's my plow truck).

Thanks for all the feedback. I'm going to look tonight and see if I can get a pipe cutter around the area ... I would hate to get metal shavings in the tranny. If it doesn't look doable, I may try RTV for a quick fix to get me trhough the next couple of snows, and then do it right in the spring ....

[solaris=amazing]

Do what curtis recomends. Plus, fuel line is dirt cheap.

I used a fuel line hose (3/16) to replace my pcv filter hose-which was badly cracked.