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I have adopted the mechanical switch that HH56 describes. It follows the KISS principle and installation is quite simple. I recommend it as replacement for the three-prong hydraulic switch that gives us so much trouble.

Packards International Northwest Regionhttp://www.packardsintnw.com/page6/page6.html still sells their replacement hydraulic switch conversion. I haven't heard if it has any problems but personally I would just do the mechanical switch conversion several of us have done and be finished with the issue.

For anyone interested, here is a photo of the 56 version. The aftermarket parts store switch is SL186 instead of SL159. You would have to swing the bracket around for 55 and verify the pedal arm distance but the geometry would stay.https://packardinfo.com/xoops/html/modules/newbb/viewtopic.php?post_id=16996#forumpost16996

The Pacific Northwest Region's little kit to convert 3-prong to 2-prong hydraulic switch works just fine, I know of many that are in service and have been for a long time, can't say I've ever heard of a problem. It uses a common 2-prong switch that's about $12 at NAPA though one is supplied with the kit, and the relay is extremely small and easily out of sight under the battery box. Installation takes about 3 minutes, no holes to drill or other modifications to make.

if you are a tinker, er,, do it your self,

all you are doing is cutting off the tl,, get the hot wire, and in line a relay, that is what the kits do,

I bought a convert set up from Steve Williams years ago never put It on,

bought it to see what was done,, my set up was the same, but I put a capacitor in .


I bet if you looked you can find a pressure switch with contacts.

it might not be cheap, it would last longer than a brake switch.

the VW switch(S) I used burned up,, my take, not heavy contacts in switch.. and I think its a metric thread.


with the relay you hear the click, when you put press the brake pedal.

I bought a 12V relay and a switch from I think a Toyota that I mounted on the steering column and is a Normally Closed switch. I have it in contact with the brake pedal arm. When I press on the brake pedal, the switch is released and the switch closes and turns on the relay which turns on the brake lights and turns off the load levelers. When I release the brake pedal, the switch is made and the relay turns off and so is the brake lights and the load levelers are turned back on. I have been driving with this for 10 years. Being an electronic technician this was an easy fix for me because I had the problem of the brake switch going bad and it seemed like a good idea. All of this is inside the car under the dash. The switch alone cannot handle all of the current of the brake lights but the relay can.

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I bought a kit from Dwight Heinmuller. It puts the brake switch on brake pedal like a modern car.

For some reason these hydraulic switches are prone to trouble. It didn't happen in the old days. I think because the brake fluids are different today.

I like the relay addition though. That would make for a lifetime installation.

For those who want to add that, let me help with the above diagram. You need the five prong unit.

Use:

pin 86 for B+
pin 85 for ground from the pedal
pin 30 for B+
pin 87a for load leveler wire (normally closed)
pin 87 for brake lights

What happens is the relay toggles between 87 and 87a when you apply the brake.

It could be that simply wiring in relays to the existing hydraulic switch will help by taking the load out of that circuit.

As has been commented on here many times in the past, the hydraulic brake light switches seem to have a shortened life when using silicone brake fluid (DOT 5). It's my experience that, when used with DOT 3 or DOT 4, hey easily last 10-15 or more years.

OD,

At the time, I was using DOT 3-4,, they would last like 2 weeks,

I didn't go to silicone till after the car sat awhile, and the dot 3-4 turned to brown sugar,

duane,g

I did all my wiring at the brake switch, and put the relay in a box, since I didn't have an org battery, there was room in the battery tray for the relay.

The new replacement brake-light switch (with torsion level) from the Pacific NW region of Packard's International is now installed. See attached picture taken from the pit in my garage. As seen the relay is affixed/secured to bolt underneath the driver's side air vent tube. The fellows that designed this kit did a neat job with design and instructions.

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