F1 front brake grabbing
 

In my '49 F1 6 years ago I fitted new wheel cylinders, master cylinder, brake lines and brake linings. Thereafter I replaced the brake fluid annually to avoid condensation issues (not using silicon fluid). New front drums were fitted 10 years ago.

Recently the front right brake suddenly began grabbing under heavy braking at speed, under light braking at walking pace speed, but with no grabbing at higher speeds with normal braking.

Adjustment checked, no leaking cylinders or oil on brake linings. I also checked for cracked drums, which had been my reason for fitting new drums after a cracked RH drum caused a violent grab - fortunately in my driveway.

I replaced both front brake cylinders and problem solved. I am surprised at the effect of what I assume was a sticky RH cylinder. The brake cylinders have 'USA' stamped on them, so assume were USA made.

Anyone experienced similar issues?

Re: F1 front brake grabbing
 

Are you getting a good flow of brake fluid from both sides when you bleed it? You don't mention new rubber brake lines in what you have replaced. They can collapse internally and look good on the outside. The left side could be bad and the right is doing the braking, causing a pull to the right. Also make sure both drums are adjusted equally.

Re: F1 front brake grabbing
 

I have had same problem... Cups inside wheel cylinders were not traveling equally, therefore creating one to push harder then other causing wheel to lock up and pull.

Re: F1 front brake grabbing
 

Have your backing plates got grooves worn on them where the edges of the shoes rest against them? I had such bad grooves that one or more shoes wouldn't sit straight, and wouldn't retract all the way. Welded them up and ground flat, no problems.

Re: F1 front brake grabbing
 

Thank you for your comments.

Barry-ct: yes, a good flow when bleeding, and I should have mentioned that all brake hoses were replaced.

Ross F-1: No evidence of any wear in the backing plates caused by the brake shoes.

Re: F1 front brake grabbing
 

If it pulls hard right while stepping on pedal and pulls left when you let up , your left rubber flex line or hard line is blocked .

Re: F1 front brake grabbing
 

I've had problems with flex lines collapsing. The above suggestion is a good way to find the problem..... Mark

Re: F1 front brake grabbing
 

if the problem is brake lines swap them around. problem should move to the other side.