Here's a better idea . . . pull the pan off and see which rod came apart. Pull it down as low in the cylinder as you can get it and cut off as much of the rod as possible. Plug up the oil hole for the rod journal with epoxy. Push that piston about 3/4 of the way up in the cylinder and use a long punch and a big hammer and peen it in place.
See if the engine turns over now. If it doesn't, stop and go get another engine. If it will now turn over, proceed . . .
Next, look at the firing order. Remove the rod cap from the other cylinder 2 places away (I'm assuming here you are working with a 4 banger). Pull that piston as low as you can get it and cut as much of the rod as you can off of it . . . Push that pistion 3/4 of the way back up the cylinder and peen it in place. Plug up the oil hole for that rod with epoxy.
Fix the hole in your oil pan. You now have a super efficient 2 cylinder engine.
