The Ford Barn

ROUTE66KIX · 11-25-2023, 10:20 PM

I have a 34 3W with 42-48 Ford brakes, unknown master cylinder, hadn’t used it for a few weeks, went to push it and it wouldn’t move, all 4 wheels locked up. A friend came over to help me and he adjusted the shoes, didn’t take the drums off, said there was no sign of hydraulic fluid on the backing plates, said the master cylinder looked fine and we were able to push the car. I didn’t push down on the brakes or do anything to it and when I tried to push it 3 days later discovered all the wheels were locked up again.
I think the master cylinder is leaking fluid to the wheel cylinders but my friend doesn’t think that is the problem.
What else could it be???
Thanx for your help

deuce_roadster · 11-25-2023, 10:23 PM

Fluid not returning back into the MC when pedal released. Rebuild or replace MC and flush out system and install new fluid.

Mart · 11-26-2023, 03:58 AM

Next time it happens try briefly undoing one or more of the bleeders. If that does the trick it would point towards hydraulic pressure being held in the system.

This could be due to a collapsed hose, in which case which bleeder being opened making it free off would give a clue.

Or it could be a master cylinder fault (blocked recuperation port or too long pushrod) in which case opening the first bleeder will do the trick.

The above scenarios would depend on the pedal being pressed, however.

It could be linked to the emergency brake not releasing properly.

Next time it happens try and determine which wheel or wheels are binding.

That will help in troubleshooting.

Mart.

deuce lover · 11-26-2023, 08:00 AM

Jack up each wheel and see which one or ones are locked up

rich b · 11-26-2023, 10:57 AM

Brake pedal binding and not returning fully restricting the master cylinder from returning fully. Easy to check, just pull up on the pedal and see if that releases the brakes.

Had this happen a lot on equipment that was used infrequently.

Kube · 11-26-2023, 01:05 PM

Sponsored Links (Register now to hide all advertisements)

If truly all four wheels are locked up, it's probably the master.

Keep in mind that the wheel cylinders will become contaminated from moisture and eventually they will lock up. The odds of all four locking up at the same time are, in my opinion, slim.
Thus, my vote for the master.

11-25-2023, 10:20 PM	#1
ROUTE66KIX Senior Member Join Date: May 2010 Posts: 3,906	Wheels locked up I have a 34 3W with 42-48 Ford brakes, unknown master cylinder, hadn’t used it for a few weeks, went to push it and it wouldn’t move, all 4 wheels locked up. A friend came over to help me and he adjusted the shoes, didn’t take the drums off, said there was no sign of hydraulic fluid on the backing plates, said the master cylinder looked fine and we were able to push the car. I didn’t push down on the brakes or do anything to it and when I tried to push it 3 days later discovered all the wheels were locked up again. I think the master cylinder is leaking fluid to the wheel cylinders but my friend doesn’t think that is the problem. What else could it be??? Thanx for your help

11-25-2023, 10:23 PM	#2
deuce_roadster Senior Member Join Date: Oct 2011 Location: Shelton, WA Posts: 3,800	Re: Wheels locked up Fluid not returning back into the MC when pedal released. Rebuild or replace MC and flush out system and install new fluid.

11-26-2023, 03:58 AM	#3
Mart Senior Member Join Date: May 2010 Location: Solihull, England. Posts: 8,755	Re: Wheels locked up Next time it happens try briefly undoing one or more of the bleeders. If that does the trick it would point towards hydraulic pressure being held in the system. This could be due to a collapsed hose, in which case which bleeder being opened making it free off would give a clue. Or it could be a master cylinder fault (blocked recuperation port or too long pushrod) in which case opening the first bleeder will do the trick. The above scenarios would depend on the pedal being pressed, however. It could be linked to the emergency brake not releasing properly. Next time it happens try and determine which wheel or wheels are binding. That will help in troubleshooting. Mart.

11-26-2023, 08:00 AM	#4
deuce lover Senior Member Join Date: May 2010 Location: Southern France Posts: 5,308	Re: Wheels locked up Jack up each wheel and see which one or ones are locked up

11-26-2023, 10:57 AM	#5
rich b Senior Member Join Date: May 2010 Location: Minnesota Posts: 1,827	Re: Wheels locked up Brake pedal binding and not returning fully restricting the master cylinder from returning fully. Easy to check, just pull up on the pedal and see if that releases the brakes. Had this happen a lot on equipment that was used infrequently.

11-26-2023, 01:05 PM	#6
Kube Senior Member Join Date: May 2010 Location: Wisconsin, USA Posts: 9,010	Re: Wheels locked up Sponsored Links (Register now to hide all advertisements) If truly all four wheels are locked up, it's probably the master. Keep in mind that the wheel cylinders will become contaminated from moisture and eventually they will lock up. The odds of all four locking up at the same time are, in my opinion, slim. Thus, my vote for the master. __________________ "I can explain it for you. However, I can't understand it for you".