patching a '72 oil tank

zotman72 · 01-26-2004, 10:19 AM

Well it would appear that my ever present oil leak (a persistent good drip) on my somewhat unique '72 oil tank is located in an circular area on the inboard side. There is evidence of brazing/patching here in this area before. As this is a copper clad, steel tank, what approach should I take to fix this problem. Brazing? Epoxy? Anybody been here before. I sure as h*** do not want to buy a new one ($$$). I suspect this might be a rust issue but no confirmation yet on that idea. Thanks in advance to any useful tips.

Tyson Schmidt · 01-26-2004, 10:47 AM

That's the same area where the sending unit bolys in. Are you sure it isn't just the cork gasket leaking?

dfw911 · 01-26-2004, 11:24 AM

I don't have the answer, but my 72 oil tank also has a circular area that looks patched up. It is separate from the sending unit, but I have always been curious as to what it was. Mine was originally a sportmatic. Does anyone know if sportmatics had different oil fittings?

zotman72 · 01-26-2004, 11:31 AM

Quite right Bart, you are describing the right place. Tyson it is not the circular area for the float sensor. I have replaced that gasket twice now. This cork gasket is the same as the fuel tank sensor and apparently cheaper if ordered as a fuel tank gasket (ask me how I know).
Anyway, the circular indentation is for mounting the tank onto the body apparently as there is a similar indentation on the body to corresponding mount/center the tank in the right location. My leak starts at that level on the body and tank.
Still looking for help.

chuckw951 · 01-26-2004, 11:59 AM

Quote:

Originally posted by dfw911
I don't have the answer, but my 72 oil tank also has a circular area that looks patched up. It is separate from the sending unit, but I have always been curious as to what it was. Mine was originally a sportmatic. Does anyone know if sportmatics had different oil fittings?

My '69 targa was originally a sportomatic. The oil tank has an extra two fittings on it that have been plugged as the car was converted to run a 5 speed 901. My tank drips as well...I'm pondering buying a new one rather than repairing or replacing it.

john walker's workshop · 01-26-2004, 12:01 PM

i just had one fixed at the local radiator shop. once the tank was hot tanked and surface prepped, there were about 100 pinholes in various places. i had them solder sheetmetal patches over the areas. same thing they do to radiators.

anh911 · 01-26-2004, 12:07 PM

Yep, what John said. You might also specify that you don't want them to paint it when they are done. Otherwise it might come back with that nasty cheapo black radiator paint on it.

Evans, Marv · 01-26-2004, 12:13 PM

Bill:
I believe the circular indentation you are talking about is one of two or three (three if my memory is correct). These indentations help the tank fit snug with the body and have some round (or nylon) wafers the fit in the indentations between the tank & body. I don't know if you can still buy them, but I would imagine you should at least improvise something to put in them when you replace the tank. As for fixing the tank, I might try to weld a sheet metal patch onto/over the rusted area and POR 15 it. Another possibility is to look around for a used tank. A "decent" one can be bought for $200 to $350. I have three in storage, but I can't necessarily get to them. One has been patched on the top area (not welded), one is pitted but the rust killed & POR 15d, and the other is pretty nice but has metal shavings in it. I'm going to be trying to find out if there is any way to have that one cleaned out. Best of luck. Those tanks collect dirt & moisture from the wheel & hold it which causes corrosion. When you replace the tank, I would do a good job of cleaning & preping the exterior & POR 15 the whole thing.

Evans, Marv · 01-26-2004, 12:16 PM

Bill:
PS - I think those circular indentations with the wafers sandwiched between the tank & body serve to keep the tank from being abraided through by vibration over the years in spots where it comes into contact with the body.

zotman72 · 01-26-2004, 12:28 PM

Guess who did not have any wafers in place this time! They were such a b***h to get in right, I punted the wafers. Still have them though. Everything does have a purpose on these cars afterall. Abrasion might have been the cause for this grief.
I was thinking a radiator shop might be a good approach, thanks for confirming that Mr. Walker.