'40 SS saloon brake system


(Graham Jordan) #1

I thought I had the brake system sorted out on my 40 saloon UNTIL I connected the hand brake.
Now when the foot brake is applied the hand brake also engages.
I can see it must somehow utilise the sliding link arrangement by the pivot point but just cant see how one can work without operating the other??
Note this is the system that the handbrake engages all 4 brakes.
Thoughts?
Regards, Graham.


(Graham Jordan) #2

Similar principle but not quite the same as my car.
I can’t see how this set up does not also engage the handbrake?


(Peter Scott) #3

Hi Graham,

When you say it engages the handbrake do you mean the handbrake lever gets pulled up when you operate the footbrake?

Perhaps some photos of your mechanism would help. I’m away from home but I don’t know if this photo of my rather oily system helps at all? (The rear casing of my gearbox has a crack in it and I’m just building up enthusiasm to repair it.)

Peter

p.s. The handbrake shaft isn’t really at an angle. It’s distortion of the photo.


(Rob Reilly) #4

My handbrake linkage has a cable which is slack when the handbrake handle is forward or off.



(Peter Scott) #5

In the Figure 7 when the foot brake is operated it pushes “C” shaped plate rearwards. The connection to the handbrake is a cable and the rearwards movement will cause increased slackness in the cable.

Peter


(Graham Jordan) #6

I installed a rod to the handbrake and not a cable.
That I did not realise.

Looks like I need to make a cable.

Thanks for that.

Jordy’s IPhone


(Rob Reilly) #7

Ok so if I understand this correctly, the reason for the slot in the clevis is so that the handbrake can pull the pair of C shaped plates without moving the brake pedal.
And the reason for the two bolts through the C shaped plates is to hold them fixed to the rod and the clevis; it is not a pivot point.


I always loved linkage problems at college. This car is like getting a new engineering toy.


(Graham Jordan) #8

Thank you Gentlemen.
I would never have realised the handbrake was operated by a cable.
The SPC is a little out in several areas relating to this '40 car.
Regards, Graham.


(Rob Reilly) #9

Here’s what my '38 saloon 40051 has.




It measures 15-1/2" pin hole to pin hole, and there is about 1/2" of adjustment either way so it could run 15" to 16" length.
cable diameter 3/16"
The cable looks like type 1x19 strand.
pin diameters 1/4"
adjuster thread 5/16" probably BSF
The pale green paint is a little known option. :grin:

There is a cross shaft with a lever on the outboard end which has two pin holes. The clevis end was on the lower of the two pin holes.

I see what you mean about the parts catalogue leaving a little to be desired. :confounded:

If you don’t find a local source, I often use www.mcmaster.com for industrial stuff like this.
threaded end fitting 3870T25
eye end fitting 3872T14
cable 3498T65 (looks like it comes in a 10 foot length)
The clevis rod end might have to be made special. I couldn’t find one with 5/16-24 UNF thread and a 1/4" pin. You could use 6071K12 and drill and tap it out to 5/16-24 UNF.


(Graham Jordan) #10

That’s excellent.

I’m going to get onto the McMaster site.

Thanks for that Rob. That truly is incredibly helpful.

Regards, Graham.