Best way to repair stripped transfer box drain threads

[Arierep]

Hi all,

My transfer box (300tdi) has stripped drain plug threads. I noticed that while tightening the plug on the last oil change. It got tight enough to seal and stay in place, but I'll have to change the oil soon and need a solution.

First of all, I'm assuming the original thread is a M12x1.5mm, is that right?

So, I'm thinking about two ways to solve the problem:

A) cut new threads and fit an oversize M13x1.5 plug.
Have I enough aluminum to do this? The M13 plug has no magnet, is this bad?

B) Fit an helicoil or similar.
I'm not familiar with this system, will it seal the fluid?


I'm leaning for A), simply because I'm more experienced with taping threads.
Any ideas?
Thanks in advance

 

[Jam1]

If you can tap a thread you will be able to fit a helicoil timeserts are better ( but cost more) as they don't do that unwinding Spring thing, both will seal and if done right will be better than a thread straight in ally.

 

[Arierep]

Sounds good
Helicoil seems to be a little safer there, as it has a smaller insert diameter.

Can anyone confirm that the original thread is M12x1.5?
Thanks

 

[Arierep]

bump...

 

[Kwakerman]

If you have got an engineering firm near by and a good sump bolt ask them to measure it, they should have a vernier and set of pitch gauges (take a packet of biscuits as a bribe).

 

[Arierep]

I have everything I need at work, except an extra bolt...

 

[Kwakerman]

I have everything I need at work, except an extra bolt...

Even easier then, get yourself a bolt (you need one anyway), measure it then eat your own biscuits!