Custom gas tank and marking leaky pinholes

[section8joe]

I narrowed a sporty tank and there are about a half dozen pinholes in the tank. How are you guys marking your tanks so you can weld up the pinholes? I filled a giant cooler with water and filled the tank with air. I see the bubbles where I have pinholes but when I tried marking the tank with a sharpie the water(from the tank being submerged) kept washing the sharpie off the tank. There has to be an easier way to mark these holes. Any suggestions?

 

[Square Circle]

Use the "leak detector" blue bubbly from hardware store.. it works great. http://www.oatey.com/Channel/Shared/ProductGroupDetail/97/All_Purpose_Leak_Detector.html

 

[zmaxmotorsports]

Are the pinholes in the tank itself or the welds?

 

[peanut]

are they rust holes or gaps in your welded seams ?

if its rust Your best bet might be to silver solder I reckon, or just use a self seal lining solution inside the tank and body fill the exterior

 

[section8joe]

No rust on the tank and the holes are in the welds. I'm going to try to spray some soapy water on suspect areas and try patch each hole. If you guys have any better ideas to identify holes let me know.

 

[zmaxmotorsports]

How about a picture?

 

[section8joe]

Ill try to post a pic later. The holes are so small that you can see them.

 

[angus67]

crayon.....