Stuck Oil Drain Plug

[moonunit]

1985 380SL Oil Pan Drain plug won't budge. I don't want to damage the pan by cranking it to hard. Any ideas? I am trying to loosen in counter clockwise.

Thanks in advance.

[rocky raccoon]

Get a long handle on your wrench and leverage that thing out. If you damage it, a new oil pan is inexpensive OR

Better yet change your oil using the suction method.

[Sugar Bear]

A few options...

As suggested use a fluid suction device to remove the oil through the dipstick. It removes more oil than pulling the plug because it goes to the extreme bottom of the pan.

Use a T type ratchet handle on the plug so that the torque is evenly applied. Load up the torque to loosen the plug and at the same time have someone strike the T handle directly over the plug. Be careful because if this works it will release very suddenly and you may smash your knuckles.

Carefully grind the head off of the plug to release the friction on the threads and then use a punch to turn the part left in the drain hole. If you cannot get the remaining plug out after grinding the head off, a new pan will be necessary.

Take it to a shop with a lift, so much more can be done just by being able to get the proper leverage.

Please keep us posted and close out the thread. Good luck!!!

[moonunit]

I am using a 1/2" socket with a 2 foot piece of pipe on it. I have the car on a lift and have lots of leverage. I am just nervous about breaking the oil pan and having to replace it. Maybe I will try the suction method.

[Hirnbeiss]

Do you have an air or electric impact? Otherwise I would try a combo of some hammering, pb blaster and heat. Then i would just go ahead and apply monster off-torque.
Make sure you replace with a copper washer - most of the time the "stuckness" seems to be from dried oil residue sticking under the bolt head.

[Campbelljj]

Is the engine hot. If not I would warm engine by running. If not able to run use a propane torch. Liberal use of penetrant ie; pb blaster. Doubt you will break pan with either of these methods.

[Ferdman]

moonunit, recommend using a 6-point socket and 1/2" breaker bar with a cheater after soaking the plug with PB Blaster for 30 minutes or so. Actually, I have been using a suction device to change oil in our MB vehicles for 10 years. Makes it so much easier not having to get under the vehicle and fooling with a drain pan.

[moonunit]

Success! Sprayed some PB Blaster on the plug, waited a couple of hours, pulled up my skirt and cranked it off with a piece of pipe and 1/2" breaker bar. Thanks for all the ideas.

[mbreturns]

I spent many years without the knowledge that " breaking the Seal " of a hard to remove bolt, screw or plug was best achieved by turning the fitting in the opposite direction. This first attempt has a tendency to break the seal between the head of the fitting and the surface it is pressing against. On numerous occasions this little trick has worked. The important thing to remember is not to try and over do it. Usually time and a good lubricant will creep into the space and as indicated above using heat helps. There is no greater sinking feeling than losing the advantage one has with being patient. Also, be sure to know the thread orientation. Left or right hand thread fittings will create some interesting scenarios in one's mind.