Tapping W59 transmission shifter housing with a 1/4 NPT tap. Thoughts?

In and as shown above, someone taps the breather hole in the shifter housing on their W59 MT with a 1/4 NPT tap in order to add an elbow barb for breather line extension.

I have the LC Engineering short shifter housing kit on my W59 MT; this raises the shifter housing about 1", meaning the breather might be kept closed by the bottom of the rubber shifter bar housing which keeps water and noise out of the cabin.

Has anyone done this mod?

Would I be able to tap the shifter housing without a machine, or can I do so using a hand tap?

 

That is a question based on your skills.

I have hand tapped many holes over the years.

Have you ever used a tap ?? get the correct drill to use with your tap.

Lots of lube. take your time . Clean the chips out as you go.

 

I would probably just close up that hole on the shifter turret. Maybe tap it for a plug. And then tap your shifter riser and put it straight fitting on that

 

Hand tap would be fine for that. That aluminum casting is super soft. just make sure you're drilling and tapping straight

 

I have only retapped previously tapped holes. You are making me realize that I should practice or, at a minimum, take my time.

That is a great idea. To be honest, I would most like to use one of Marlin Crawler's short shifter kits; however, I called them and they have no plans to manufacture any for the W59 transmission, sadly.

I wonder. What would I even use to plug the hole? I guess a threaded plug, like you said?

Thanks, bud.

 

I did something similar to my R150F tranny and Tcase with barbed Nylon fittings rotary-filed down until they would press-fit into the smooth vent holes. They were sealed with Ultra-Black with no drilling/tapping needed. Once the Ultra-Black dried, the barbed Nylon fittings were very durable.

 

You’re a genius! Do you remember what size those are? 1/4”? I think I have an old breather I might be able to measure laying around.

 

I used 3/8x1/4 MIP barb fittings to match up with the breather filter located high up in the engine compartment near the brake master. But there are several size filters to choose from.