Brake light pressure switch
 

I have seen , either here or the late V8 forum, that some guys are replacing bad brake light pressure switches with a pressure switch from Harley-Davidson. I thought I had written the part # down, but can not find it. anyone know what the part # is ? The switch on my avatar has gone bad, and I need a good quality switch to replace the one on the car. Thanks for any help anyone can provide.--- Jim

Re: Brake light pressure switch
 

I think that Speedway has it.

Re: Brake light pressure switch
 

I've had them all fail. If there is a Harley dealer near you any parts guy with triple digit IQ can find you what you need. It may have the spade connectors instead of the bullet.

Re: Brake light pressure switch
 

It's odd. After over 60 years and dozens of cars (from "winter beaters" to complete restorations), I have never had a problem with an original Ford brake light switch.

I wonder what I'm doing wrong?

Re: Brake light pressure switch
 

Maybe because you are not messing around with Dot5.


Just a guess


Bruce

Re: Brake light pressure switch
 

Are they somewhat universal? I found some NOS Raybestos ones at a swap and picked them up since they are good 'ol USA. Thread pitch is the same for the end of the master.

Re: Brake light pressure switch
 

Per an older thread:
Ken tx posted the part number as - H D brake light switch #72023-51C made in USA.
V8coopman posted that it was superseded by #72023-51D.

The -51D appears that it might be a little different style to me. The Blue Streak part number claims to fulfill requirements for H-D -51A, -51B & -51C. CECOMINOD025083 Standard Motor Products Blue Streak Stop Light Switch MC-SLS2

Re: Brake light pressure switch
 

Because I use Dot5 I use the mechanical lever type switch from the early Chevy pickups. You can find them on e-Bay or at most local auto parts houses. Cost about $12-15.

Re: Brake light pressure switch
 

FYI: The Harley switch failed for me and it cost more too.

Re: Brake light pressure switch
 

Someone here or on the HAMB posted a link for a low pressure switch. I've got the info at home in the shop. If no one posts the info I'll post it later today. I bought one and so far so good about it working and working on a lower pressure

Re: Brake light pressure switch
 

Mechanical switches are much more reliable. Take a look at the '58 - '66 Corvette switch. Easy to mount and quite cheap

Re: Brake light pressure switch
 

Also, think of the safety aspect...A mechanical switch provides brake light activation much earlier when the pedal is tapped.

Re: Brake light pressure switch
 

I tried Dot-5 in a Corvette once. It worked, but was such a PIA to get bled that I never used it again.

It would be interesting to find out what kind of brake fluid the guys experiencing problems were using.

Re: Brake light pressure switch
 

The low pressure switch was from Classic Performance Products in Placentia, CA 800-522-5004 Part number CPP-LBPS They list it as 45psi. Cost in August was 16 bucks plus tax shipping included.

Re: Brake light pressure switch
 

I had an original GM switch from a 1937 C*******T in a coupe I owned from 1991 until I sold it last year. I had DOT5 in it since I bought it and changed the brake fluid once in all that time, about 10-years ago. I averaged approx. 2k miles driving per year with the car. The brake system was working fine when I sold the car last May. That was roughly 28-years with no problems.

Re: Brake light pressure switch
 

I have got them at N A P A, they had the correct bullet connectors, don't take much pressure to activate brake lights, I use dot 5 fluid

Re: Brake light pressure switch
 

Thanks for all the answers and information, it is all very useful. The car is in storage for the winter, so there is no hurry on the repair, now I just need to make a decision on which way to go. I like the idea of the mechanical switch, but not sure how I would mount it with the pedals going through the floor, an not being swing down pedals. there is not much room under the car for anything. I will have to take a look at things. my brother has come up with a few NOS Ford pressure switches, so I may try one of those first since the price is right. Thanks , ---Jim

Re: Brake light pressure switch
 

I went to purchase a brake light switch from a Harley dealer for a friend who used Dot 5 and insisted on an HD brake light switch because HD uses Dot 5 fluid

The dealer told me HD hasn’t used Dot 5 in over a decade. Since all their bikes now have abs systems they have been using Dot 4.

Same brake light switch in my 49 using Dot 4 for over 18 years, no problems.

Tom

Re: Brake light pressure switch
 

If you can do it, go with a mechanical switch. I changed all my cars to a mechanical switch - if the switch is adjusted correctly, the brake lights go on instantly when the pedal is pushed. No worry about the guy behind you.

Re: Brake light pressure switch
 

I pondered this and was going to try drilling the pedal and putting in a momentary push button that you would step on every time you hit the pedal. just run the wire along the the pedal arm. A little ingenuity and it could be done. You could use it in conjunction with the brake switch so if one failed the other would work.
Something like this where you could drill and tap the pedal and lock it from underneath so it protrudes just enough. Paint it black and it will barely be noticeable.
https://www.amazon.com/Heavy-Utility...P6V0E7NXEWX1H6