Packard Forum Index » Post-War (1946-54)

This must be the season for Easamatic brake light issues! My 56 has started to do the same thing recently, and pulling up the brake pedal doesn't seem to correct it. I will try the suggested simple measures first, but I have a few questions:

Do you recommend getting at the master cylinder from above (lying down on the engine after removing the heater vent tube and baffles on the left side? Or is it better to put the old girl up on ramps and work from beneath? In any event, I will clean the whole assembly before opening up the cap.

Another similar post suggested using a sewing needle to poke open the vent, and possibly, if opened up, the compensating vent hole inside. If opened, what's the likelihood that I will need a new screw seal on the master cylinder cap. Should I postpone this step until I have a replacement in hand?

My car has the glass jar remote filler device. Does that affect the venting issues and does it have the same vent hole in the square drive cap?

Finally, I take it that simple, non-synthetic DOT-3 fluid is recommended. If I open up the master, should I try my best to get out all of the old fluid and replace it with new? I suppose that lots depends on what I find once I get down to the darned inconvenient thing. The people who designed master cylinders higher up on the firewalls deserve some thanks. To think that I used to own Bendix stock.

The system on your car is way different than the one on the 47 in the other post--no sewing needles are needed or wanted here. Since you have the optional remote reservoir the cap on the brake unit is not vented--otherwise the contents of the remote reservoir would be on the floor.

The next time your brake lights stay on open a bleeder screw at any of the wheels. If they still stay on you have a switch issue.

If you do end up taking the cap off for a look inside, do it from above--unless you have AC in which case you are out of luck. Just suck the old fluid out with a turkey baster. If you look in through the hole you will see the end of a little valve. When you step on the brakes you will see that valve stand up straight. When the pedal is released it should lay over to the side a bit. Let us know your findings.

Of course if your brakes have been requiring drinks of fluid more than say once a year, then the master cylinder needs rebuilding--and the other cylinders need looked. And that is true whether it is Treadlevac or manual.

Changed fluid in reservoir with new DOT3. Installed new gasket/grommet on easamatic reservoir wrench cap. Vent holes on wrench cap free and clear. So far no more sticking brake lights. Thanks for your invaluable assistance in diagnosing my issue. Keep you posted.

Brake lights still sticking on after a brief drive. Will throw in a ten dollar brake light switch and see if that solves it.

For any Packard except the TL cars, a NAPA/Echlin SL-134 is the correct switch.

I ran the "not-venting" theory by the previous owner (for 44 years, and before that, his father, a Packard mechanic) and he said that it made sense to him. He recalled rebuilding this car's Bendix system about ten years ago, and said that it could be time to do it again. But first, he counseled, try the bleeder valve release the next time it's convenient, if the brake lights come on by themselves.

There are other automotive priorities to be dealt with in the meantime with car shows and other brands. But once a set of four jackstands can be freed up in the garage, up goes the Packard for a good look beneath.

With some help from Hemmings, I have begun the search and pricing of rebuilding my Treadle-Vac. Quite a range of prices, but only Kanter has exchange units in stock to minimize the down-time. Any opinions on which way to go once (and if) I have the brakes apart? Like Randy, I'd prefer to keep the car original and still have reasonable confidence that the Bendix engineering won't let me down. But if I'm to spend the money, I want a reasonable assurance that the work will be done right and the brake pedal will behave for the next dozen or so years of moderate driving.

After changing reservoir fluid and cap gasket, solution finally turned out to be the stoplight switch. I removed the old one, manufactured by FASCO of Rochester, NY and cleaned it up as possible future spare, and for car history. It seems like it must have been the original or been replaced a very long time ago. If original, I would say I got my money's worth from that 60-year-old part. They probably don't make them like that anymore:)