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Since we have had the discussion about rubber longevity with some of the other repro items, here is another item for comments.

Packard used the same seal for the clutch and brake pedal shafts for many years. I am wondering about the longevity of the originals. I don't recall ever seeing an intact seal or one in very decent condition but then most of the cars were well used by the time I got to look at them.

Here is a repro from the usual source that split apart at the thin bellows section. Both split at the same place with the other one also cracking in half so a part fell to the floor. To be fair, I won't hazard a guess as to how long ago they were purchased so may have been well dried out -- but was supple when installed and was only on the car for about a year. The car hasn't moved in that time so the pedal springs kept the seals mashed against the floor plate. There doesn't seem to be any limit or adjust for the pedal height in that direction so I am wondering if the pressure is too great. Hard to tell if the seals were mashed too hard or were dry or the rubber is just not as good.

Anyone have any recent experience with how their repros are holding up and how long they have been installed.

Rather than spend another $35 to replace these right away, I am going to try my hand at a repro first. Will make them out of soft urethane with similar shape but slightly different design.

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A couple of suggestions:
use an aliphatic urethane, not an aromatic. It will stay supple longer.

the part is breaking at aa stress riser - use a gentler radius there

Should the pedal shaft hole area be larger, so the rubber does not flex as much? Does this seal have a felt piece like the V8 brake bellows do?

If you do redesign, would having more bellows like the V8 brake pedal give the seal more area to flex help?

HH, this is probably the time/place to use a silicone rubber for long life and elasticity. Gloss won't show up / matter down there.

http://www.dowcorning.com/content/rubber/silicone-rubber.aspx (there are others)

Quote:
There is nothing but the rubber -- no felt. A narrow but thick formed portion that fits snugly over the stem and rests against a flat support area joined by a single fold bellows affair to a wide flat upper rubber that fits against the opening.

I am not totally convinced the bellows portion is completely necessary yet. Obviously Packard did but in looking at the pedal and how it moves up to the floor plate and seats against the opening on this car, I am not entirely sure a flat or slightly conical thick but soft cushion wouldn't work just as well. It only has to lightly press agains the floor plate and be flat. With no adjust or stop for upper pedal height and without any rubber in the middle, the springs keep the pedal support area tight against the hole area. If the seal is about 3/8 thick it will duplicate the compressed Packard piece and spring should keep it tight.

I made something out of dense foam rubber reasonably close in looks to how the original is in its compressed state. It seemed to seal well so used it for a pattern to make a mold. I have some soft urethane left over and will cast my version tomorrow. Machined a slot in a fender washer to fit the shaft so will cast that into the pedal support side so there will be a wider surface for the pedal to push against. If necessary a sort of pivot can be added to the metal so upper side can move on the pedal support area to match the floor plate. Don't think mine can be any worse than the piece that it replaces. Will see how it looks and works in a day or so.

Quote:
The silicone is probably a good idea but I have the left over urethane which is now in an open container and has to be used soon anyway.

IDEA: Rather than reinvent - sometimes these parts fit across lines so maybe look at some of the competitive seals to at least get some ideas - might have been supplied by the pedal/shift assy people - like Wagner or their suppliers. They made the brakes and someone made the clutch, etc. P didn't make everything.