Seized gear box oil drain plug

[scoot39]

I have been searching the forums for tips on how to free up a seized gear oil drain plug. Bought a used Puma 50cc with 100 miles on the odometer. Changed engine oil which was a pretty straightforward procedure, but upon going to the gear box drain plug, I noticed that the ends/ shoulders of the plug were rounded. I was able to fit a closed end 10mm wrench on the plug, but was unable to get any movement. You probably can guess the rest. More force, right. That resulted in more rounded corners, and no progress at all. Next tried a sharp punch to make an indentation on a flat side of the plug, and attempted to gently tap at an angle to get movement. No progress again. Also tried a heat gun on the case only before using the punch again. Again no progress. Short of putting a pipe wrench on it, I've run out of ideas.

Other questions are would the use of compounds such as Liquid Wrench help in a situation like this, or a propane torch on the plug?

[gsx600racer]

A tool like this.

Impact driver.



and some heat should to the trick.

[90GTVert]

Vise grips may be another option. Not sure that you'll get anywhere with them given the other steps you've tried, but sometimes they'll do it if slipping is a big problem.


Since you should be replacing the plug, there are magnetic drain plugs for these (usually sold in a kit with engine and gearbox plugs). They're a nice upgrade IMO.

www.scooterworks.com/Prima-Magnetic-Oil-Drain-Kit-Genuine-GY6-Kymco-QMB139-P1566.aspx

[badpumpkin]

My opinion would be to use reverse drill bits. As they drill, they apply heat and pressure counter clockwise. You can find them at auto parts stores.

[scoot39]

Thanks for all the responses!