"Grabbing" Brakes

[Smiley]

I have a problem with the brakes grabbing in reverse on my 1932 RP.  I have to reverse out of
my garage down a gradual slope. The brakes make a horrific noise when applied.  Has 
anyone experienced the same problem and if so how did you cure it ?

[Roland Alcock]

My Opal has started that malarkey. 
Braking in reverse is like a 10 foot scaffold pole has been suddenly driven into the ground. Such is the violence of stopping. 

Observation shows lots of movement in king pins and some movement in spring shackles. 
So the axle twists making for a self servo action on the brakes. 

Remedial work takes place very shortly. 

Roly

[Nigel Ricardo]

Just (well 3 weeks ago ) had the same problem on my RN , I have changed the brass cups and bolt, I found one radius arm needed tightening and also replaced the spring shackles and bushes. Unfortunately, that's as far I got because when I overreached for a spanner I slipped 2 discs and been laid up since.

[Smiley]

My Opal has started that malarkey. 
Braking in reverse is like a 10 foot scaffold pole has been suddenly driven into the ground. Such is the violence of stopping. 

Observation shows lots of movement in king pins and some movement in spring shackles. 
So the axle twists making for a self servo action on the brakes. 

Remedial work takes place very shortly. 

Roly

Thanks Roly,  I'll be interested to see how you get on. I don't have King Pin problems but spring shackles could be the cause.  I'll check those. Cheers.
Smiley.

[Ian Williams]

In my experience the above comments are valid, almost certainly the axle twisting, the brass cups and chassis ball often being a major culprit, also check for loose brake shoe pivots and shoe adjustment.

[Smiley]

Just (well 3 weeks ago ) had the same problem on my RN , I have changed the brass cups and bolt, I found one radius arm needed tightening and also replaced the spring shackles and bushes. Unfortunately, that's as far I got because when I overreached for a spanner I slipped 2 discs and been laid up since.

Hi Nigel, Sorry to hear of your problem. Excuse my ignorance, but what brass cups and bolt do you refer to ?
I'm not too mechanically minded but am still prepared to have a go. Still learning.
Smiley

[Andy Bennett]

Is it only in reverse?
I had similar problem but when going along (33 RP) after 30 mins or so.
I had just adjusted brakes and it turned out that I had taken up all the slack to the point where with just slight pedal application it all caught up, with loud banging and grabbing, ie either off or full grabbing on. I basically loosened everything back just a fraction to give a little more slack in the cables to give me room for a gradual application of the pedal and all was good again.
Andy B

[Smiley]

Is it only in reverse?
I had similar problem but when going along (33 RP) after 30 mins or so.
I had just adjusted brakes and it turned out that I had taken up all the slack to the point where with just slight pedal application it all caught up, with loud banging and grabbing, ie either off or full grabbing on. I basically loosened everything back just a fraction to give a little more slack in the cables to give me room for a gradual application of the pedal and all was good again.
Andy B

Hi Andy, Thanks for your reply. Yes it is only in reverse gear.  No problem after moving off.  I check the hubs for overheating after a good run
and nothing to worry about there.  Cheers

[Nigel Ricardo]

The brass cups are in the end of the radius arms on the cross member below the gearbox with a bolt and spring then the nut.

[Roland Alcock]

Just (well 3 weeks ago ) had the same problem on my RN , I have changed the brass cups and bolt, I found one radius arm needed tightening and also replaced the spring shackles and bushes. Unfortunately, that's as far I got because when I overreached for a spanner I slipped 2 discs and been laid up since.

And that’s exactly why I am going to wimp out and pay a grown up to sort it out!
Yes I will be 70 in 5 months, if anyone was wondering. 
Roly