The Stovebolt Site Forums The Shop Area Engine Shop Oil pan cracked and leaking...ok to weld?

So, My son parked the truck in the driveway and I asked him to move it so I could get another car out. When he backed up, I notice a very large puddle of oil on the driveway. Looking under the truck, the oil was dripping from the bottom of the pan just head of the drain bung. Luckily this happened at home and upon checking the oil level was one quart low and on the driveway. He pulled the truck in the garage and I placed a pan under the leak.

So, my plan is to drain oil (assuming it has not already all leaked out), tape off crankcase vents in valve cover (216 engine), grind paint off oil pan at crack and weld up the crack. My thoughts are that taping off vents will prevent air from entering the engine and any internal fire from the welding process will be quickly snuffed out from oxygen starvation. However, I am concerned about seeping oil fouling the welds.

Question: Does my plan seem sound? Do I risk burning down the engine? Will the oil foul the welds? Any other suggestions short of removing the oil pan...don't want to?

TIA.

If your going to braze the pan leak then at least pull it. Even if drained sludge could remain and with the heat ignite.
And yes the oil will contaminate the job.

If you do not want to pull the pan, then use a patch epoxy for short term.

There is no way to get enough oil out of the pan to prevent it from contaminating your weld. Pull the pan, pressure wash it inside and out, and find the ends of the crack. Stop-drill the ends with about a 1/16" drill bit to keep the crack from spreading as it's heated, and braze the crack closed. By stopping up the vents you're going to be creating a bomb once the oil inside the pan gets hot enough to flash burn.
Jerry

Just in time for the 4th of July with that oil pan bomb, Jerry!

Would the pan need to be heated up prior to brazing it?

(DavidF, I'm just curious about how to go about this & not stepping on your question- it is about required to pull the pan to clean it, though. That metal needs to be Mr. Clean for any welding.)

Brad

No preheating will be necessary. About a #0 or #1 tip on an acetylene torch will do a fine job of applying silver solder or brass. I'd probably use silver solder to minimize any possibility of extending the crack from overheating the thin sheet metal. It's also possible the leak is from a rust pinhole, which will be obvious after doing a good cleanup to bare metal, inside and out. If that's the case, the weakened area will be much bigger on the inside so the patch material will need to be applied to the inner surface.
Jerry

I would start looking for another oil pan.

David, if you have to pull it, might as well just weld it shut. You have the skill set to do that easily since you did your whole truck. I am not 100% sure, but I THINK you can pull it without doing anything special. Just unbolt and slide it back and it should come right out.

David is good enough with sheet metal work to easily patch whatever is wrong with an oil pan.

If your patch weld doesn't work, I took an oil pan off a '51 216 you can have.

Rick

I dropped the oil pan on my 49 216 in-truck without any problem. It cleared the front axle and only required the rear 2 piece inspection cover to be removed.
It was unexpectedly heavy and was a handful for one man laying on my back to R&R. Another set of hands will make reinstall alot easier.

Good luck.
Dave

Here is another option for you to consider.

My most recent experience ; oil leaking from around the sump bung , sump cracked .
Drained oil , fitted bung , evacuated the oxygen from the crankcase by flowing Co2 (from the mig welder bottle) thru it for a while , sprayed brake clean liberally around bung area , mig welded the crack.

All good .

Thanks all. Deve is right, I have the skill set to mig weld the crack closed, even lying on my back. I am just concerned about the residual oil left in the engine. I don't think tape on the VC vents would result in a engine bomb. Come on guys, over the top hyperbole, in my opinion. My thoughts on the tape would be to oxygen starve any fire that might want to start.

And, there is no sludge in the engine/pan as I have put less than 1000 miles on the engine since rebuild.

If consensus is to pull the pan, then that is what I will do. but, I think spot welding the crack very slowly (i.e. let the metal completely cool) will prevent the oil from igniting. Contamination might be a real issue, but I will know soon enough.

Edit: I will run a test - I will butt join two scrap pieces of sheet metal and oil soak one side and attempt to spot weld the seam from the bottom side. Test result will tell me whether or not I can successfully weld the oil pan in place.

When I finaly found the leak in mine was from the threads being stripped I had a friend mig weld a 1/4" backing plate on the inside which I drilled and tapped. Good as new now.
He was certified pipe welder... I'd of blown through for sure.

I edited my post above. I think a test will tell me a lot. Blowing through will not be an issue for me.

Rick: Thank you. I may take you up on your offer if my test/experiment fails. I probably will let this issue sit for awhile as I have to leave town next week for 1 week. Probably wont get to it until 7/11/15.

It's fixed. Experiment worked fine, so went ahead and welded the small hole closed on the pan. Yes, it turned out was a small hole, not sure what caused the hole. One quick spot weld and it was fixed....and no fire.

So, truck participated in 4th of July parade and ran fine. Then, later in day experienced engine trouble. New thread started...