I have a 2 piece oil pan. It has a threaded fitting in the side of the oil pan. I am assuming it is for the return line from the oil filter. Problem is... is does not go through the oil pan. It is solid on the inside. Can I just drill it out so it is a clean passage back into the pan?? Check out the pics. Thanks in advance for all the help.
That's odd and not factory. I would assume you could drill through. I would drill through the outside going is to make sure it lines up. Seems high on the oil level though.
looks to me that the pan had been used with a full-flow oil filter set-up where the discharge from the oil pump exits the side of the pan and is routed up to the filter then into the back oil gallery on the block. Someone brazed a 'slug' over the hole.
I'm assuming pre '49 and that 2-piece means the removable clutch pan...?? If so, that looks like the filter returned for a few years until the filter return got moved to the dipstick boss casting. '49 up engines put the return through the block casting right above pan. If I am correct, all you need is a hole, using whatever drill will go in there without hitting the threads.
You could thread a nipple in to protect the threads. Drill a pilot hole from the outside. Then drill a bigger hole from the inside.
That isnt a solid plug, take an inspection mirror and look up (towards the pan rail) from the bottom of the pan. It is a drilled return passage. I have 4 oil pans like that currently. I will grab some pictures of one if you'd like. Let me know Brant.
Pays to have the thought of why I had 4 pans with no oil passages, so I drilled one out... They don't go back into the pan correctly after that! Haha