Brake light switch

[TomJ]

Okay...this is driving me nuts.  I've installed the second brake light switch, and just like the first one, it leaks. Now I'm wondering if I have a bad fitting for the master cylinder. I was looking at it before I put the second one in and the part that is threaded for the brake light switch to screw into isn't threaded all the way in which doesn't let the switch screw in to the point it tightens against the fitting inside.  Don't know if I'm describing this in an understandable way, does this make sense, anybody else remember having a problem like this?

Tom

[1955CJ-5]

You might be right, the fitting may be worn. I believe it is a tapered thread so it just tightens up, it does not bottom out to seal.

The threaded portion of my switch is about 3/8" and there is still about 1/8" remaining when it starts to tighten up....but it continues to turn until it tightens and does not bottom out or run out of threads

Are you sure the copper washers were OK when you assembled� the master cylinder or have you not had it apart?

[athawk11]

Good thought Randy.  I was wondering if Tom is missing the washer...?

Tim

[Macgraham]

I got a new switch from Ron at G503 and it leaked around the pressed metal and plastic, not on the threads. Got one at a local Car Quest that worked.

[Paddy]

Here are a couple thoughts as I went through this as well.  First make sure you have a new copper washer, secondly make sure that switch is really really really tight so that the copper washer deforms and thus forms a seal within the threads of the master cylinder.  If your body is off this is a lot easier.  If your body is already on, then I would recommend removing the front driver's fender for easier access, obtain a 24mm deep socket and a long extension for your ratchet and then crank that rascal down.  Yes 24mm and it has to be a deep socket to get around the electrical prongs so that you don't damage them.  If all that fails your final two solutions are permatex #2 on the threads or replace the master cylinder.  My guess is, you haven't cranked that switch hard enough to form a seal with the copper gasket.

[mtnman37879]

I just installed a brand new switch from Quarter ton and military jeep parts. It leaks where the plastic meets the metal. JUNK SWITCH!

[Carls_jeep]

Brake light switch, ARRRRGGG.
Been my experience that that they only last a year and they leak or fail to work or both.
Leak at the metal to plastic- REPLACE IT.
Leak at the pipe thread- you should have used the paste Teflon  thread sealer on it and it doesn't have to be extremely tight.
If the brake lights fail and shorting the wires together at the switch make the brake lights work replace the switch. Shorting the two wires shows the wiring to the switch and the brake lights are working and the switch isn't.

finally, I hope you have better luck finding a brake light switch that lasts more than a year. That is, if your jeep is driven a lot all year long. Garage Queens don't have that problem.

my Jeep, Annabelle Lee, gets 6000 to 8000 miles a year. Most of it in Utah and Arizona.

[mtnman37879]

I have found the brake light switch that is sold to fit Willys are crap, all of them. Buy a switch made to fit a Ford. You'll have to change the wire ends but the switch will last.

[Marla.the.V35]

I have found the brake light switch that is sold to fit Willys are crap, all of them. Buy a switch made to fit a Ford. You'll have to change the wire ends but the switch will last.

Does anyone have a part number for this? Looks like mine might be hosed and I'm already going to have to replace the brake line to the rear, so might as well do this now.

[tow hook]

I used a sealer of some sort on mine , it’s been on a year no leaks