2005 BLN11341. My 420D has 2 oil plugs. The one I removed must have been cross-threaded by the previous owner. I took it all the way out without even thinking about using the other plug. This one will neither thread in the oil pan straight, nor tighten. Is there a method to permanently block this outlet and just use the other plug? Not really wanting to replace the entire pan. Something like JB weld even an option at this point?
Ahhh , found some devices on Amazon that may do the trick.
yeah. helicoil kit.
JB Weld fixes everything!
But would Jb weld fix itself…….
Yes, Jbweld is an option. Obviously the threads are scuffed nice and clean. Hook a vacuum to the other drain plug, clean the damaged one well with non flammable brake cleaner, coat both the plug and hole with JBmagic, screw it in as tight as it goes. run it in 24 hours. What's the amazon device you're considering? Plenty of ways to re thread a hole too if that would let you sleep better at night.
If you are experienced with brazing using an oxy/acet torch --- that would be a guaranteed permanent fix for it to never leak.
I inserted a Dornan plug for now. I’ll have to figure out what I want to do for the long run. I did retrieve a spring-looking piece of material from the oil outlet. What is that for exactly? Could that have been causing the misthred issue? It did look deformed while inside.
That spring looking piece is for the spring looking piece holder inside the engine, now your spring looking piece holder will be missing it's deformed spring looking piece sorry, couldn't help it. Picture maybe?
Spring looking piece sounds like a ruined heli coil. Fix it using a time sert. https://www.timesert.com/
Weld a pipe coupling to the pan then insert correct size pipe plug
But for how long?? They do sell oversize drain plugs that tap the threads a bit as it installs
This is the spring looking thing. With this thing out, the plug feels 2 sizes too small.
^^^^^^^^ it is too small, that is the remnants of a heli coil.
Insert?
Yes, that's the same thing as a helicoil. Possibly made by heli coil, even if sold by Case. That one was not installed correctly as far as I know, the "tang" across the center is for installation and is supposed to be broken off after installation. I don't know if that contributed to the failure or not. You may not need the heli coil tap if you can buy the spring part separate. If the threads aren't damaged, just way too big, AND the thread spacing is the same, the plug threads should fit perfectly into the pan hole threads on one side.
This is what it looks like per part#
If you do reinstall a Hili-Coil install it with red loctite. Just make sure you don't get any on the drain plug or it will become more or less permanent. Put it in with red loctite, install drain plug to make sure it fits, then remove drain plug and let loctite dry overnight before putting in drain plug.
I think it is a safety spring that prevents the drain plug from backing out in case it was not tightened sufficiently. I don't think Caterpillar would be installing heli-coils in new oil pans. IMHO. Nige will give the final and accurate verdict. Below is from the 420D parts manual.
Don't know what to think? your picture of the stretched out spring is definitely a helicoil, and it matches the picture of the insert exactly. They both show the notch where the tab should have been broken off. The parts diagram shows a conventional compression spring with more coils, but could be just a representation. I agree, I would not expect that to be standard, it would be a repair part. But what do I know?...
I can't speak for Caterpillar but I have seen automotive oil pans like that. Cast aluminum pan with thread insert from the factory. Makes for a strong thread.
I may just pick up the insert and see what happens at my next oil change.