Damaged Oil Tank Removing Line - Can it be repaired?

[frankc]

Well, after reading the various horror stories of damaging the thermostat when removing the oil lines, and given that mine have been on the car for 31 years now, I decided to not even try using a wrench on them and just cut the fastener and chisel it off as many suggest, as I am replacing the lines anyway. This worked like a charm and I had both lines off the thermostat in about 20 minutes.

I used a Dremel to cut into the threaded part of the fastener and I would stop ever few seconds to see when I reached the aluminum threads, and then sprayed blaster in there. This worked very well as the difference in metals made the transition very visible as shown below:



The damage to the fitting threads was minimal and should not affect the seal at all:




However, the line at the oil tank is another story. I thought this fastener would not give me any trouble as it is a brass fitting (I believe). I used blaster on it with heat cycles for several weeks, but I could not get it to budge with a wrench and hammer (another reason I chose to not even try a wrench on the thermostat fittings). Not wanting to rip the fitting out of the tank with too much torque, I decided to cut this fastener as well. I tried to avoid this because as you can see in the photo, the tank is in the way of the cut-off wheel, preventing you from cutting directly on the threaded part of the fastener. So, instead I cut on the hex part hoping I could use the slot to chisel the nut off. Well, I used the same procedure where I stopped every few seconds and checked, but I never saw a transition in metals - until it was too late and I saw a hole . I sprayed some blaster in there and the fastener came off without too much trouble with a chisel, but look at what I found under it:



So, my question, of course, is can this fitting be repaired? Please say yes .

thanks,
Frank

[x98boardwell]

Sorry, I can't be of any help, but wanted to see what they say. Looks like a great idea to me.

Bryan

[Walt Fricke]

Ooouch.

I'd consider soldering, brazing, or welding the slot, but just on the sealing surface. Then file it and stone it as smooth as you can where things mate and seal. Then use the mating end from the line you removed (suitably modified so the nut doesn't get in the way) and valve grinding compound to get it back to a 360 degree seal (checking with bluing).

You can stuff something you can later retrieve in the hole while filing or using grinding compound, lest any small stuff get in. I'd not worry about a piece of solder or braze getting in if something breaks off later, though, as it ought to get caught in the filter, which is where this oil goes first.

Won't be easy, especially with the tank in the car. Which is a bullet you may have to bite, sooner or later.

I don't know what these fittings are made of, but I do know they can be brazed.

Here is how I fixed stripped threads on the drain (with the tank out of the car).



Nothing like the precision machine job you will need to do with hand tools, though.

Good luck

Walt

[frankc]

Walt,

Thanks for the suggestions. The tank is coming out of the car anyway, so no issue there. I was wondering if a radiator shop would be able to do this kind of repair. I'll call around on Monday and see what they say.

Frank

[914efi]

Double check where the seal is actually created, that edge part might not be doing anything. It looks like the area below it (shiny part on ID) is where the sealing surface is. Can you rig up a simple pressure test?