meadowfield 2,545 #1 Posted June 2, 2020 (edited) After pouring oil in, and losing it on the floor on my K301 on a C-121... the remote oil drain on the engine base was snapped off. I welded a nut into the broken piece to get me going. Anyone help with what thread size? Assume by the rough size it is 1/4-18 NPT thanks Edited June 2, 2020 by meadowfield Share this post Link to post Share on other sites
pfrederi 17,147 #2 Posted June 2, 2020 Pipe size may vary depending on the oil pan. Most of mine are 3/8 NPT This chart may help you figure out what you have 3 1 Share this post Link to post Share on other sites
squonk 38,917 #3 Posted June 2, 2020 Yes most of mine are 3/8" NPT 1 Share this post Link to post Share on other sites
meadowfield 2,545 #4 Posted June 2, 2020 thanks - was hoping to not have to drain the oil to pull it and see I think I welded a 3/8UNC nut inside the hollow section to get me going Share this post Link to post Share on other sites
pfrederi 17,147 #5 Posted June 2, 2020 OD of 3/8" NPT is about 11/16" Share this post Link to post Share on other sites
meadowfield 2,545 #6 Posted June 2, 2020 10 minutes ago, pfrederi said: OD of 3/8" NPT is about 11/16" In my mind I think the small piece I extracted from the sump was about 1/2" and very thin walled, so a 3/8" UNC bolt would fit inside (small amount of thread turns down on a lathe. Unless of course the thread was 11/16" and I fit a 1/2" bolt inside... darn - I can't remember Share this post Link to post Share on other sites
pfrederi 17,147 #7 Posted June 2, 2020 on K301 they used several different pipe sizes for drains. 1/8 1/4 3/8 depends on your spec # Share this post Link to post Share on other sites
meadowfield 2,545 #8 Posted June 2, 2020 I guess the head size on the bolt tells all! Share this post Link to post Share on other sites
meadowfield 2,545 #9 Posted June 22, 2020 Turns out it is 3/8” NPT.... bought both sizes just in case 1 1 Share this post Link to post Share on other sites
