Oil Pan Drain Plug

[chuckg]

I must have over torqued the oil pan drain plug in a 1995 S 420. (so much for torque wrenches users). The drain plug turns in either direction using a socket, but will not snug or back-out.

Working on jack stands I tried using a vice grips to tug downward on the plug while turning in counter clock wise. This did not remove the plug. This problem is becoming a small annoyance, since I am losing a few drops of oil each day.

I hate to pay to replace the oil pan since this involves raising the engine to remove the pan.

What can I do to try to remove the plug (and see if the plug threads are stripped rather than the threads on the pan?

[deanyel]

If I was in your shoes I'd take the pan off - not that hard to raise the engine.

[Hatterasguy]

Well what I would do first is buy a new drain plug and see if the old threads will bite enough to allow you to tighten it so it doesn't leak. Really all you need is a small wrench, just a 1/4 of a turn past hand tight is usually enough.

If that doesn't work you can re tap the threads, no need to replace the pan.

[t walgamuth]

i agree with hattie.

tom w

[manny]

You can also buy slightly over-sized, self-tapping drainplugs.
Though I've never had a problem with my drainplug ( I'm one of those torquewrench guys ), I know there is about 3/4" of " meat " on the oilpan where the drainplug threads in.
That's plenty enough material to re-tap to the next size up.

[shandy]

The way you describe it you have stripped the threads on the drain plug but part of the plug with intact threads is projecting past the threads in the pan and preventing the plug withdrawing. I can't think of any way you are going to remove it without dropping the oil pan ,and even then you may not be able to get it out . I hope someone wiser than me may have a solution .
Geo.

[deanyel]

Originally Posted by t walgamuth

i agree with hattie.

tom w

But hattie has assumed the removal of a plug that won't come out. Such liberal use of assumptions is normally limited to economists.

[Nipperiley]

Before you give up, I would continue to try the vice grip method and at the same time have an assistant try to force a thin blade of some type ( like a paint scraper , thin blade screwdriver) in between the drain bolt and the pan. Maybe once you get it started a bit, it will screw out.

Taking the pan out will be a pain in the ass. As a last resort you could clean the surfaces well and use RTV sealant to stop the leak. Then use the "pump out" method for future oil changes.