VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 oil pan

I'm interested in what causes the pin holes in a perfectly solid oil pan and how to fix. it doesn't look like rust more like electrolysis. I'm thinking a good cleaning with a bead blaster then a couple coats of epoxy paint inside and out would make it last a lifetime.
Jay D.

Hello badsix,
If the oil pan pin holes are random, then I don't know. If they are along a level horizontal band around half way up or more from the bottom, I tend to think of two things that may be a cause. Acid along the top of long standing oil (years) eching at the unpainted inside metal. Moisture from atmospheric cycles above the oil level from years of sitting. Just guessing. Epoxy should work so long as the prep work is done well.

Oil turning to acid causes the holes. I used JB Weld on inside after cleaning well worked great. Will push through hole to outside. JB Weld sands well. Paint outside after repair. I had mine power loaded looks great.

Most often the holes are caused by water droplets against the metal. These droplets are sites for electrolytic corrosion of the steel. Each should have a darker center and be a relatively smooth rounded crater. Others will look like they were drilled. It is a common problem with long term storage, more so in humid climates but also in dry ones where cold winters cause water condensation inside engines and gas tanks.

thanks, I was just amazed that there were pin holes right in brite shiny metal. there was a slight amount of sludge on the bottom so maybe acids in the sludge or water trapped there. anyway I like the JB weld idea.
Jay D.

Just for your information, if the corrosion is from acids in the oil (comes from burning sulfur and oxidizing nitrogen or carbon) it will be over a general area and irregular (because of the irregular composition of the steel matrix). Adsorbed water is generally also necessary for significant corrosion.