Rear brake split pin discipline

[PeterBo]

On the attached picture, I show the rear brake drum on my 1929 Model A. You can see the that the emergency brake pins all have split pins but they face the inside of the car and hence are not easily visible. The rear service brake however has split pins that face outwards from the car and although hidden from view, can only fit this way else they interfere with the brake's movement. They therefore are opposite to the emergency, parking brake. In both cases, the pin orientation is as per Les Andrews manual and so I assume this is the way Ford designed them as original. The emergency brake pins could be reversed as far as I can see and then ALL pins would have their split pins facing outwards from the car - a much more uniform approach and allowing checking to be much simpler.

My question is, why would Ford have originally designed the brake movement pins to have this opportunity orientation? Seems odd or an oversight to me.

Any clues?

 

[Dave Slater]

I'm pretty sure if you reverse the pins they will foul the brake drum. Is that a Hassler Shock I see? Dave

 

[PeterBo]

Yes Dave. There are Hasslers on each side of the rear but no shocks on the front. These have operated faultlessly since I bought the car five years ago!!!!

 

[john charlton]

Dave is right if the flat topped clevis pins are assembled with the split pin outward the innermost pin can rub on the hub .The other pins will not foul but I expect they were assembled on the line before the innermost pin was fitted .If there is any wear on the axle taper and hub it will rub for sure .

John in lovely sunny day first day of autumn Suffolk County England.

 

[SeaSlugs]

Dave is right if the flat topped clevis pins are assembled with the split pin outward the innermost pin can rub on the hub .The other pins will not foul but I expect they were assembled on the line before the innermost pin was fitted .If there is any wear on the axle taper and hub it will rub for sure .

John in lovely sunny day first day of autumn Suffolk County England.

Correct, theres a reason why the emergency band pins have a low profile head.

 

[1955cj5]

When I first got my pickup and inspected the brakes I found the e-brake clevis pins installed opposite the correct way, with the split-pins outboard.

You can see the wear...through to the pin hole on one..

No doubt there is some wear to the axle taper and hub that contributed.

All repaired now with Randy Gross brakes and drums, and a taper shim...

Note the baling wire on the one clevis pin. All the back plate nuts were pinned with baling wire as well!

 

[PeterBo]

Many thanks guys. As I now look at it, you are correct and the inner clevis pin would foul with the drum. Seemed odd when reassembling but you are correct.

 

[J Franklin]

I think the band was assembled to the shaft and then the unit assembled to the backing plate during manufacture.