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I ruined the threads on the torque converter drain hole and don't know what to do
I did something incredibly dumb. I was changing the transmission fluid on our '14 E350 Wagon (722.96). I had the torque converter drained, new filter installed, and the cleaned pan bolted back to the transmission. It's time to reinstall the torque converter drain plug, but before doing that, I decide to copy a YouTube video I saw of a hack to make getting the plug in and out easier—since the axis of the plug doesn't intersect the area of the port hole on the bell housing, the maker of the video drilled a hole at the edge to make it so that the two features intersect. Nevermind that I got the plug out and can get it back in without doing this! It's late at night, I'm not thinking, I get out my drill, and as I'm drilling it the bit slips and **goes into the torque converter drain hole, ruining the threads**. I can't get the drain plug back in now and I don't know what to do because I can't think of a way to repair threads without getting debris inside the torque converter.
Can I somehow fix this without the transmission coming out and the torque converter being replaced? Is JB Weld a dumb idea? The car has 125k and in the event we still have it at in another 70k miles when the next service is due I guess I could replace the torque converter then.
Metric thread repair kits can be found on Amazon or probably at most auto stores. If you're dealing with a magnetic bell housing, use a magnet to catch the thread shavings. If aluminum, use vacuum suction. Either way, re-thread the hole in small increments to limit the rate at which the shavings are shed (turn the repair tap in a fraction of a turn, then out several turns so the shavings are extracted). If the threads are damaged beyond repair, you might need to tap the hole for the next size larger drain plug.
Metric thread repair kits can be found on Amazon or probably at most auto stores. If you're dealing with a magnetic bell housing, use a magnet to catch the thread shavings. If aluminum, use vacuum suction. Either way, re-thread the hole in small increments to limit the rate at which the shavings are shed (turn the repair tap in a fraction of a turn, then out several turns so the shavings are extracted). If the threads are damaged beyond repair, you might need to tap the hole for the next size larger drain plug.
The slots in the threading tool are for putting grease in like posted. Had to do the same thing tapping the exhaust manifold on my truck. Works really well. Scarier on the torque converter IMHO.
Sometimes I wonder, why can't MB specify a proper location for TC drain plug to their TC makers ?
After all the service manhole is already there, fixed location.
Mine and my friend's W204 C200 2010 TC drain plug is good mid center to service manhole, but some as OP car is offset so bad, he need to go thru this kind of trouble... duggghhhh.
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IF you are doing this solo, any wireless camera or boroscope can help you find the TC drain plug while spinning the main damper pulley.
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