My Willys 3A and 3B Community

3A, 3B, DJ Technical Knowledge Base => "Original"-- Technical Questions, Answers, Observations => Topic started by: allen on September 16, 2011, 04:42:20 PM

Title: Pressure switch on master cylinder is leaking
Post by: allen on September 16, 2011, 04:42:20 PM
I changed the pressure switch out and it is leaking around the threads where it screws into the brass fitting. I removed it and put some thread sealant on it but it's still leaking. Is there a specific sealant I should use because of the brake fluid? I changed it once before and never had this problem. The first time the switch came from NAPA and the second one that leaks came from walcks ( love that place).
Title: Re: Pressure switch on master cylinder is leaking
Post by: Gunslinger on September 16, 2011, 08:50:08 PM
There should be a crush washer between the switch and the MC, it needs to be a new one each time you pull it.  Youjust can't seem to get a used one to seal.
Title: Re: Pressure switch on master cylinder is leaking
Post by: Carls_jeep on September 18, 2011, 10:26:01 AM
The brake switch is a pipe thread and screws into the banjo bolt the holds the brake line adapter onto the master cylinder. There is a copper washer on each side of the brake line adapter and if they are not leaking and the threads in the banjo bolt are and sealer will not stop it you may have to replace the banjo bolt.

There is a thread sealer made by Locktite that may do the trick. If you can't find that then use the mild bolt retainer locktite. Most people over tighten pipe threads. They figure keep turning until it stops and all that does is over stress the thread and maybe split the female threaded part.

Perhaps you or someone else has over tightened the brake switch and stressed the threads.