brake drum gets hot brake drags

[Colin Jansen]

I have ensured the wheel bearings are set right, the shoe adjustment is not too close, the anchor points are not binding, and have replaces the slave cykinder, yet intermittently the right front still gets stuck on and drags, but not all the time. Only started happening after taking drum off to clean up and adjust brakes in right front what else could it be causing this drum to intermittently heat up or at least the shoes to stay on in this wheel.

[41jeeps]

What happens when you open the bleeder when the drum appears to bind ?

[Colin Jansen]

Every time the drum had bound up has been when ive had it out on the road, it always behaves as it should when testing "Hold and release" in the workshop so have not had the opertunity to check the bleeder when dragging. What is your suspicion?

[artificer]

First check you have correct pedal free travel @ the master cylinder.
Then you have only a few possibilities if only the RHF is troublesome.
Adjustment, sticking wheel cylinder, faulty flex hose @ RH steering knuckle.
When the problem is apparent releasing the brake bleeder will allow any pressure build up caused by a faulty flex hose to escape & the wheel should turn freely.
You don't need to be on the road just jack up the vehicle on the RHF & pump the pedal a few times....if the hose is faulty nothing needs to be hot to duplicate the fault which will be apparent with the wheel locking up or brakes dragging.

[wingnut1]

Hi. I had the same problem some years ago on both front wheels. changed master cylinder and flexable hoses checked adjustment again and again wheel cylinders seemed o.k. In the end it turned out it was cheap made in some grass hut wheel cylinders that caused the problem. after that episode i only bought my parts from a reputable supplier .
Regards Bernard.

[r40ford]

Colin,
When you had the drum off and cleaned things up did you install the brake linings with the long lining on the forward side? Did you notice any slots worn into the backing plate where the linings slide? Did you bleed the system after doing the work? Just some thoughts.

Regards
Bill

[Colin Jansen]

Hi guys

It is only the RHF side with the problem. I am just in the process of putting her back together after taking the backing plate off as well to ensure all is clean and eccentrics are traveling properly when adjusting. Replaced one upper eccentric and filed a few burrs off anchor points and parts but they have always been free previously anyway but thought i would do it with them off. There is no rubbing evident on the backing plate but there is a slight mark on the front of the shoe plates where in fits into the locator halfway up, so filed that lightly too.

As for the slave, it was doing dragging with the original one and is still doing it with the brand new one i just fitted so may not be the slave at all. The slave is brand new from Marathons in Aussie.

Yes the linings are the right way round, and yes the system was bled

When jacked up, and with pumping the brakes up real well it has always released as it should. Only ever happens on the road.

[Jerry Hudgens]

I want to higly encourage you to check your flexible hose feeding the wheel cylinder. I had a similar problem on my 1968 Mustang and I worked and worked trying to figure out what was wrong. I finally took the flexible hose off and tested it with a guage and air pressure and sure enough it was bad. It had a real bad restriction but it allowed pressure to go to the wheel cylinder when I applied the brakes but it would not let the pressure relieve when I took my foot off the brake. Strange.

Jerry Hudgens

[Colin Jansen]

Cheers Jerry, so far the flex is the only thing i have not replaced as i dont have a spare in my parts shelf. Trying to get her sorted quickly for a local Xmas parade on the 27th, but i think i will order a couple from Big Al and hope they get here in time.

[artificer]

Get one made locally by Pirtek, Enzed or similar outfits in NZ. They can do it for peanuts, while you wait.

[Colin Jansen]

Finished re-assembly and bleeding but ran out of time to take her for a test run today so hopefully tomorrow i will know if its all sorted

[jean marie]

I also had the same problem as Jerry Hudgens and his Mustang, the front left brake was dragging, the reason was the flexible between the master cylinder and the front axle, in my case there was less clearance on the left side brake so the right brake looked ok.
The reason is when you apply the brakes the pression is far more important than when the brake release and the fluid does not return easyly through the flexible.

[41jeeps]

A failing flex line will swell under pressure.
One can hold the line in his hand while someone else push the brakes.

[Colin Jansen]

Well guys

She is back together. The following has been done or checked:
a) New Slave
B) Eccentric and anchor point adjusters all round have been cleaned up recoed or replaced and adjusted as per the manual to .008 top and .005 lower
C) Shoes clean and free to travel at pivot and other points, not impacting anywhere.
C) Master has 1/2 Inch free travel as per manual
D) System bled as per manual
E) New flexes ordered

I finally got to test run her (Was mending Cam Nets all morning) and i put her through some excessive emergency stops. She is now showing the following symptoms.

A) All drums are now warm to hot with the front two more so, whereas before the rears and left front were always cold (How warm should they get normally)
B) Seems to brake evenly
C) i can no longer get her to lock up whereas she would before on hard braking
D) the Brand new slave is leaking i think due to a defective bleeder

I am now thinking that like Jean Marie its the flex from the Master to axle and binding on one only was due to adjustment closer than the others

[jean marie]

The 4 drums are hot now? That's another story

Did you change/open your master cylinder?

Sounds to me now that you have a wrong setting of the MC and the fluid does not return through the by-pass.