So I've been chasing problem after problem on this car for months. but I'm getting down to the end - or at least let me believe that, thank you.... I've had a small oil leak under the car that I was attributing to a leaky main seal. As I crawled under and around yesterday, I see it's actually the fill plug on the side of the trans case that some ham hands cross threaded the last time this car was checked over. I put a wrench to it but a more-than-gentle tug wouldn't budge the plug to remove it. I'm wondering if I should attempt to get this out and get it threaded in correctly, of if i'm asking for trouble and a tow into a shop if I don't get it back in there straight. I'm guessing the worst thing to do is get it out and run a tap through it. Thoughts on what I should do going forward?

 

Cross threading can be a nightmare. Getting a tap started straight after being cross threaded is 50/50 at best. be sure to fill the tapbreliefs with grease to retain any chips you might make when retapping. Do you know what threads they are ? I am wondering if they are straight or tapered threads (I am assuming pipe threads).

 

I would guess pipe threads as well, so I wouldn't run it completely through. I didn't know if little bits of the thread that might fall into the case would be deadly or not - though I suppose I've seen Muncies full of totaled gear teeth that kept on going lol. But grease in the tap would keep anything from falling in.

 

The best way would be to pull the trans and try to re-tap it with it out of the car. It isn't but about an hour each way (out and back in) to remove the Muncie.

 

The other thing is.... you want the tap to follow the path of the original threads, which means it has to start radially in the same place.
Take a pic of the plug as it now with a ruler along side.
Then, the first step is to get the old pipe plug out.

 

If not successful and have to take it to a shop, use an expanding rubber plug temporarily to drive it there.

Good luck!!!

 

That is a great idea. OK, now I don't feel like I'm stranded without hope lol. I'm at least going to try and get the plug out and who knows - maybe thread it back in the correct way without having to do anything drastic....

 

Success success success I got the plug out with a little extra effort, chased the threads with a die, then took the 1/2" tap with grease and set it square, running it backwards in the opening to catch the start of the threads by feel.... Then I slowly turned it forwards to catch the old threads, making VERY sure I was as square as could be, but only ran the tap about 1/4" clockwise, total - just to where I could feel that it caught and was in the old threads. Then backed it out, got the plug, started it slowly, and it caught as it should and went all the way in. Leak stopped, worry stopped; Ham Hands defeated again! Thanks, everyone

 

Teflon tape is your friend on NPT fittings.

 

GREAT JOB !!!!!!!! You did everything just right and it worked.