Brake pedal return spring

[pmdavies]

Hi Everyone

So, the new master cylinder is in - piece of cake, don't know what all the fuss was about!! I now need to fit a brake pedal return spring. Two problems: I don't have the spring and there doesn't appear to be anywhere to hook it to.

However, I inherited a box of brake parts which includes some springs which aren't the shoe return springs, so they may be the pedal return springs. Does anybody have one in their garage they cound measure so that I can check. Also, can anyone tell me exactly where it hooks onto? How far down from the pedal pivot is it?

Many thanks

Pete

[Pikey]

The Brake pedal return spring looks very similar in size/shape to the throttle return spring on the carburettor. As regards its position one end should fit to a welded on bracket in the bottom of Chassis member in front of the pedal and the other end fits onto the Clevis pin linking to the master Cylinders push rod. Unfortunately for you I believe you have to take the Master Cylinder out to fit it.

[bigginger]

You dont. It can still be a pig though

[bmcecosse]

Provided the little bracket still exists in the chassis member!

[bigginger]

Indeed.
a

[bmcecosse]

I suppose if it's gone - it would be possible drill up from below and either simply hook into the hole - or put a little screw up through with a new bracket attached.

[rayofleamington]

It's actually quite easy to fit when you have the knack. Sadly it took me a few years and a lot of skinned knuckles and swearing to find 'the knack'!

1) Make sure the pivot pin (the one that attaches pedal to M/C pushrod) is free to rotate. If it's stuck in place, then this method won't work very well. Having tried other methods, I'd free up a stuck pin rather than try anything else.
2) Hook the far end of the spring into the chassis leg. To do this you can move the pedal to it's uppermost position - this 'just' allows hand access into the leg.
3) Get a 2 foot long piece of (strong) electrical wire and assorted screwdrivers and thin nosed pliers. Make the wire into a loop and attach one end of the loop to the near end of the spring. Wrap the other end of the loop round your fingers/fist.
4) Pull hard on the wire to stretch the spring. (If it hurts your hand too much then fit a bar in the loop and pull on the bar). Use various tools to offer up the sping hook to the hole in the pivot pin. If the pivot pin hole isn't quite in the right place, rotate the pin with the pliers, and try again. Rotate the pin a bt after the spring is fitted to make sure it is well located on the hook - and not just on the tip of the hook.
5) when the spring is securely in place, remove the electrical wire and press the pedal lots of times to watch it spring back, and feel very proud...

Once you've got the hang of it this way can be done in minutes (max). Don't feel too bad about struggling - this job can take hours if trying to do it without using a loop of wire.

[bmcecosse]

Useful tip !

[kennatt]

after several attempts to fit a new spring to mine I did the following unscrewed the plunger to pedal rod by undoing the locking nut and turning the plunger rod. they eventually separate and leave the pedal and rod free from the master cylinder and the plunger still held in the cylinder by the rubber cover.once disconected the pedal and rod were free to move away from the master cylinder.the spring is then fitted with out any problem since it is not under tension.Then by pushing the pedal down against the spring the rod and plunger can be mated up and screwed back together then re adjust the free travel.tighten the lock nut and job done.

[pmdavies]

Thanks everone for the info. I obviously need to make a bracket but the remaining question is how far forward from the yoke pin should it go. If anyone can remember or estimate it that would be great. Another way of looking at it is how far do you have to stretch the spring when fitting it? The reason I'm still fishing is because the position of the bracket will obviously affect the tension on the pedal. Many thanks, Pete

[Orkney]

Just been and measured on the trav whilst the floors up, from the pin in the pedal to the hole in the bracket its four and a half inches.
Cant help wondering if a bolt right through the box channel would do the job instead of a new bracket?

[wibble_puppy]

thanks very much ray and kennatt for those extremely useful tips!!! *makes notes for when I have to refit my spring*

wibble xx

[Judge]

It's actually quite easy to fit when you have the knack. Sadly it took me a few years and a lot of skinned knuckles and swearing to find 'the knack'!

1) Make sure the pivot pin (the one that attaches pedal to M/C pushrod) is free to rotate. If it's stuck in place, then this method won't work very well. Having tried other methods, I'd free up a stuck pin rather than try anything else.
2) Hook the far end of the spring into the chassis leg. To do this you can move the pedal to it's uppermost position - this 'just' allows hand access into the leg.
3) Get a 2 foot long piece of (strong) electrical wire and assorted screwdrivers and thin nosed pliers. Make the wire into a loop and attach one end of the loop to the near end of the spring. Wrap the other end of the loop round your fingers/fist.
4) Pull hard on the wire to stretch the spring. (If it hurts your hand too much then fit a bar in the loop and pull on the bar). Use various tools to offer up the sping hook to the hole in the pivot pin. If the pivot pin hole isn't quite in the right place, rotate the pin with the pliers, and try again. Rotate the pin a bt after the spring is fitted to make sure it is well located on the hook - and not just on the tip of the hook.
5) when the spring is securely in place, remove the electrical wire and press the pedal lots of times to watch it spring back, and feel very proud...

Once you've got the hang of it this way can be done in minutes (max). Don't feel too bad about struggling - this job can take hours if trying to do it without using a loop of wire.

.......or use a pair of Mole grips

[bigginger]

Not much room for those in there

[Orkney]

......or use a pair of Mole grips

Tried a pair of pliers last night and ended up breaking the spring

[wibble_puppy]

blimey!! i don't think i could break my spring with a bulldozer

[bigginger]

Hmmmmm - 40 year old spring. stretching - you don't need a bulldozer, believe me

[pmdavies]

Thanks everone for your invaluable info

Pete