Out in the Sunshine and Seating the Brake Shoes

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Finally finished (enough of) the tasks needed to bring our Pierce out of the storage garage. Feels great to actually drive it again, even just up and down the subdivision hills. Had to ride the brake pedal hard to seat the shoes into the drums, as neglected by previous owner(s). Had to put the car back on the jack stands three times and re-adjust the shoe eccentrics to recover pedal travel during this adventure. Still not perfect, but improved from “full panic mode” up to “white knuckle scared”.  Several more afternoons of seating shoes, the brakes should be acceptable enough to drive home for an oil change and radiator flush.  Herb

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Thanks for the picture of a real pretty car

 

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Beautiful car.  I’ve never used one, but you may want to find someone who has the machine which “trues” brake shoes to the drum.  I wouldn’t think you’d be having that much trouble with the brakes if the shoes were mating properly.  Great that it’s on the road!

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Herb, if you want to call me, I will put you in touch with the man who completely redid the brakes on my ’36.  He trued the shoes to the drums, redid the whole system.  It turned this car from an uncontrollable 3 ton missile, to a proper stopping car with affectionate vacuum noises and everything

 

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Herb,

 

Beautiful car, getting a little too close to Carolina Blue though.

Are your brake linings molded or woven?

Glad you are mobile and I would rather have my car stop than go if I only had a choice of one or the other. It isn’t a Bugatti.

Bill

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IMHO a beautiful color. I had well over 30 samples mixed adjusting to try to get to that look. Light yet still conservative. I didn’t quite get there, but at some point one has to move on.

Looks great! Hope you get the brakes sorted out.  My first round with 4 wheel mechanical brakes were bad until I learned the sequence to tighten the shoes until they cinch the wheel then tighten all the cables as tight as feasible then back off each wheel to almost dragging. It was like rear wheel brakes only until then.

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That is a sharp color. IMHO you can’t go wrong with blue.

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Thanks for all the complements on my Pierce, I do appreciate it and want to show it soon. I can tell that very few miles were driven during the last several years, so I will attend only local shows this summer. Building some driving hours will loosen things up and help smooth them out. Next year’s goal is driving to the Glen Falls meet but there is more stuff to sort out before going that far.

The brake shoes are molded and do seem to have about the right arch for the drums, or at least close enough.  As expected, the steel drums have wear ridges and grooves around the braking surface. However, the shoes looked brand new and were very smooth across their faces. Having no mating grooves to fully engage all the drum surface really reduces actual contact area. Breaking in new shoes to match the drum’s actual surface profile will make the the brakes much more effective with more actual contact area between shoe and drum. After three cycles of run the brakes hard and then adjust the shoes on our last adventure, the old battery decided we were done for the day.

More hard down hill runs and then adjustments will wear the shoes for more stopping power, which is the immediate goal. We also seem to have significant lost motion in the pedal travel before the shoes contact the drums, likely from wear in the rod clevis mechanisms.  Reworking all the clevis joints should cure much of the lost motion – but is a task for next winter when I can organize my tools and equipment around the car in my new garage.  Herb

 

 

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Brovo    Herb looking good .

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Great to hear that another Pierce is back out on the road where it belongs.

Hopefully it’s just the pins that are worn and not the yokes on the rods.

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I have replaced the brake clevis pins on several cars.  On one more worn than expected, the yokes were also pretty worn.

The original pins were .375″ [3/8″].  I bought some 7/16″ pins which are .435″.  Using an adjustable reamer, I hand reamed each yoke and rod. Then measured the new hole diameter.  Most cleaned up at around .400″.  I then turned the oversize clevis pins down to the correct size for each clevis.

Before replacing the worn pins into the reamed clevis’, this particular car had about 1″-2″ of actual brake at the bottom of the pedal travel, which was quite dangerous.   The free play in the pedal was about 6″ out of roughly an 8″ total travel.  And this was with the brake shoes adjusted to the point of dragging..

With the new pins installed in the reamed clevis holes, the brake pedal had the least free play on any S80 or S81 I had ever driven or worked on. So the effort was worth it.

Note: turning down a .435″ diameter pin in a lathe requires a pretty high speed lathe.  And the proper cutting tool for the lathe..

Greg Long

 

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