how to "fix" your oil pan for under $100
So, in case some other poor soul decides to look at this thread in search of information. Here's what I went through in repairing this problem.
First: The previous owner's JB weld repair was so contaminated it popped off very easily with a screw driver, and I found the small hole(s) that were the culprits. I let the pan drain for 2 days, yes 2 days, it was still dripping.
Second: , I borrowed an disc air sander from a buddy and used a rough grit pad to clean the bottom of the pan. The disc sander was a charm and just the thing for this job. I really spent a good amount of time on this, and got it to bare metal and did my best to scrub with a wire brush around the pitting and such.
Third: After blowing it off, and wiping it off with brake cleaner and making sure it was all clean and prepped I sprayed a rust reformer paint on the pan to try to stop any little rust gremlins present and prevent future ones. (without contaminating anything inside, obviously) Most of this was waste and removed afterward
Fourth: I TRIED (very hard) to put a fresh, JB patch over the hole with the intent of then patching over that with other stuff ... I really put serious time and energy into cleaning and prepping and keeping the thing from getting contaminated. First attempt, failed utterly. Second attempt, I gently put a very slight upward dent in the hole in the pan with a wood handle. (aka so that the hole was "higher" than the surrounding metal slightly. I was thinking that any oil build up would settle away from my JB hole while it cured. It looked beautiful, but it too failed. In frustration, after seeing some stuff on you tube on this issue, I put a small vacuum on the mouth of the oil filler to help put a vaccuum on the system and "pull" oil away from the holes to prevent contamination ... this resulted in the JB wanting to pull into the pan itself ... I decided that was BAD as I don't want chunks of JB working through my internals, so I stopped it right away ... Fourth attempt, forget it, JB weld sucks and is crap, I've literally NEVER seen a good repair with it, I gave it a great chance, i moved on.
Fifth: I cleaned the pan beautifully (AGAIN). This time I started by using a fast setting fiberglass repair kit intended for fuel tanks that I picked up at Auto Zone. I figured if it can hold up to fuel, it can hold up to oil. Now, the trouble with this was that working quickly under the truck on the ground is a B*&#H. I first pre-cut my fiberglass into small appropriate shaped pieces that I could apply. Then I mixed my epoxy and set to work. In theory, with fiberglass you want to paint it on the surface to apply to, then apply your fiberglass, paint another of coat of resin over that to soak it, repeat per layer. Trouble is, in that wicked little space, by the time I had mixed the 2 part resin to my satisfaction and got a layer painted on the pan, then applied the cloth and began painting over it, the resin set too fast and I couldn't actually finish completely painting the outside layer of resin... but the cloth was impregnated from the front and there and seemed solid. For the record, this patch was about 3 square inches around the hole of resin and fiberglass.
Sixth: I carefully re-sanded the new patch to get rid of drips and creases and make it a nice bonding surface. I even blended the edges with the pan. Then I used a slower setting fiberglass kit meant for body repairs (also purchased at Auto-zone). This one had a 10 or so minute cure time IIRC. I made 2 much larger patches that covered basically the whole front of the drop in the pan, and which also wrapped around the front corner, and up the sides a little and shaped around the drain plug area. I put it on as described, 2 separately done layers with a light sand between, meaning a total of 3 layers of fiberglass over the hole, with a nice wide coverage of connection around the holes and the edges of the pan.
Seventh: I went ahead and painted black heat worthy paint all over the repair in several layers and let it dry (some of it with engine heat in the next step
Eighth: I put oil in, prayed, and watched for leaks.. I drove a little, prayed, watched for leaks, I drove some more, rinse and repeat, and in the end, I now am almost due for an oil change, haven't added any oil, haven't dripped anything but a very slight smudge due to the drain plug, not the pan. I've rechecked the repair again and again, and it seems to be holding really well. I wouldn't call this a permanent repair, but I'm pretty happy with it, and have relaxed a bit about it and don't check it every day now, or at all really. Now for some pics
2003' F350 7.3L Lariat Crew-Crab 4x4 6spd Manual Short Bed. 3.73 ratio and that's about all i know... so far.