Does anyone know what the thread size is for a 12mm banjo bolt? It is probably M11 by something. I tried to match it up at NAPA but they go from 10mm to 12mm. If there is a 7/16 extra fine thread it may match too.


Here's what I am trying to do. The front brake line looks like this now:



I want to add a brake light switch like this, and was going to tap the tee to make it fit:

 

Never mind - it's 7/16-24, and I ordered the tap

http://www.dragspecialties.com/products/?productId=475088&partNumber=BL77544CH

 

never had luck in doing that - the threads are rolled not cut in brake systems and they don't like each other

in the aftermarket masters it does seem to work out using that in the end of a master but not in a line fitting

 

I suggest you find some Loctite 542 hydraulic sealer, you'll need it for that rig it'll never quit leaking without it. I use this stuff regular with custom brake & multiple fitting setups. Take a long hard look before you get busy drilling & tapping may not have enough meat left when done, maybe have an extra tee handy too.

 

Maybe this would be better? I am thinking I can drill and tap the 7/16 port deeper to eliminate the inverted flare seat...

https://www.jegs.com/i/Earls/361/972051/10002/-1

 

Run into the same issue drill & tap deep enough for the new banjo fitting you may wipe out the needed flare seats for the other 2 lines. Somebody makes a fitting for what you are doing check Russel or Goodridge.

 

If you installed one of these adapters here...you could run a regular rear brake light switch.

 

Thanks Tom, I was just thinking of replacing the brass elbow with a tee and getting a regular brake switch.