Surge Brake Problems

[bruceb58]

I always adjust drum brakes so they just slightly touch and never had an issue like this.

From an E Trailer article:

Basically you will adjust the brakes out so that there is a slight but constant drag of the pads on the drum when the wheel is turned.

Article is first in this search:
https://www.google.com/search?q=etra...utf-8&oe=utf-8

 

[Mellisa7]

That is exactly how I have always adjusted these brakes for 20 years. I don't know what is going on ?

 

[Lou C]

Aha.
​I had a similar issue a few years back and here's what I found...
​Kept loosening the adjustment, and still had this issue on one side.
​Took the drum off and found:
​a bit of corrosion between the galvanized shoe and lining, pushed up the lining about a half of a mm, to the point where the lining was cracked. Just swapped in a new backing plate and back to normal. If you have the kind of drums with the adjusting hole on the outer face, see of you can spin the drum, and look inside with a bright led flashlight and see if the linings are cracked.
Other things:
​if only when it sits they could be rusting to the drums, I've had that happen too but only first time in the season. I adjust mine so there is no drag and it helps.

 

[Mellisa7]

OK maybe we are getting somewhere? Yours did it when it sat and rusted to the drum? But mine will do this over a 6 to 8 hour period.
I can adjust the brakes a little looser, but then it bangs harder when applying the brakes and bangs harder when taking off from a stop.
again, the brakes work perfectly, until I dunk them in the water and return a few hours later?
But, I have lots of things to check. I am thinking I will take a wrench for the bleeders, if it does it again I will crack the bleeders and see if there is pressure that will release? Crazy I have to think of this the whole day on the water.....Should be having fun lol

 

[dingbat]

OK maybe we are getting somewhere? Yours did it when it sat and rusted to the drum? But mine will do this over a 6 to 8 hour period.
I can adjust the brakes a little looser, but then it bangs harder when applying the brakes and bangs harder when taking off from a stop.
again, the brakes work perfectly, until I dunk them in the water and return a few hours later?

There should not be banging no matter how loose the brakes are set.

"Banging" is caused by excessive travel/ bottoming out of the actuator from air in the system.

When my coupler is properly bleed, I get no more than a 1/4-3/8" max. actuator travel

 

[Mellisa7]

Agreed on the air ! But the looser the brakes are adjusted the further the actuator has to travel to push the shoes out to meet the drums. Correct me if I'm wrong ' but air in the sustem and the brakes being adjusted too loose will have the same effect on the master cylinder.... I also get about 3/8 travel when pushing the actuator manually. Totally appreciate everybodys input.

 

[bruceb58]

I will ask this for the 3rd time...Have you actually pulled the drums off and inspected everything in there? For example, someone who is over zealous with a grease gun could have blown the rear seal and grease over brake shoes makes them stick like crazy!

 

[Mellisa7]

I take my drums off every year. I inspect everything! All bearings cleaned and inspected. Looking for pits or dark areas that have been hot. New double lip seals installed every year. I get a kit to rebuild wheel cylinders every year. Less than $10 to rebuild wheel cylinders. I run a brake hone through the cylinders to clean up any rust. I am a maintenance freak maybe? No need to get crazy with the grease gun. I have seen people pump it full and grease all over the brakes and drum. Not the case here. Drums and everything cleaned extremely well with brakeclean and blow dry with air.
So, yes everything has been inspected and maintained to prevent problems. I hate problems.
Almost every trip to the lake, you will see some guy on the side of the road with bearing problems. I do NOT want to be that guy lol.
But I have an odd problem that will be resolved eventually once I can narrow it down specifically
Been to the lake 3 times this year and all four brakes locked up when going to retrieve the boat.
No problem whatsoever when pulling boat up the ramp empty and parking . Last time out, I rolled the truck back and forth a few times to make sure everything free. perfect! Come back 8 hours later, locked up???????
.

 

[bruceb58]

I will ask again for the 4th time...Have you pulled the drums and looked in there since all this started happening?

BTW, rebuilding brake cylinders is a crap shoot. They are so inexpensive, way easier to buy new ones and if you buy new ones, you should get the aluminum ones.

I wonder if you have a bad residual valve in your master cylinder causing excess brake line pressure. You don't use a backup solenoid do you?

 

[Mellisa7]

No, I have not pulled the drums since this started happening! How can this simple rebuild be a crap shoot? There is nothing in there except a spring rubber, and dust boot?
There is no back-up solenoid....
Where can I get aluminum wheel cylinders?
I understand and appreciate all the questions and opinions! But, what happens when they work perfectly, and then they don't work after dunking in the lake????? The only thing that changes is they get wet and then sit in the heat of the sun????? The brakes stop perfectly, and release perfectly when towing to the lake. I feel the wheels all the time and they run cool?
Maybe a new Master Cylinder would be a good place to start?

 

[fhhuber]

You back down the ramp with the boat on... boat weight and incline work to keep the brake off.
You are still on the incline, and towing which would act to keep the brake from engaging as you go up the ramp.
Hit the brakes of the tow vehicle after you get on level and... you have brake drag until you get the boat back on the trailer.

That would be the spring is not providing enough tension and the geometry of how the tongue mounted actuator system works, with the weight of the boat helping hold the brake off by pushing down on the tongue, thus the ball lifting and rocking the actuator a bit.


Tighten the tension adjuster... maybe 2 turns.
Try it.
If its better but not cured, do another turn.

Adjust the tension to where you can slowly back up a very slight hill slowly without dragging.

Stop playing with the drums, brake cylinders and master cylinder.
Its the hitch

 

[Mellisa7]

sounds like a plan !

 

[dingbat]

Correct me if I'm wrong ' but air in the sustem and the brakes being adjusted too loose will have the same effect on the master cylinder.... I also get about 3/8 travel when pushing the actuator manually..

an increase in brake clearance does not equate to increase actuator travel.

Fluid displaced by increased caliper travel is made up by the fluid reservoir at next actuation.

3/8" "manually" is way too much. I'm talking 1/4-3/8" travel under normal braking conditions.

 

[Mellisa7]

an increase in brake clearance does not equate to increase actuator travel.

Fluid displaced by increased caliper travel is made up by the fluid reservoir at next actuation.

3/8" "manually" is way too much. I'm talking 1/4-3/8" travel under normal braking conditions.

If we were talking about DISC brakes I would agree. These are drums.
If the brakes are adjusted all the way loose, the actuator won't even move far enough to apply any brakes at all.
The springs on the shoes pull the brakes back where they started and the next actuation will be the same as the first.

 

[Mellisa7]

an increase in brake clearance does not equate to increase actuator travel.

Fluid displaced by increased caliper travel is made up by the fluid reservoir at next actuation.

3/8" "manually" is way too much. I'm talking 1/4-3/8" travel under normal braking conditions.

If this were the case, why would you ever have to adjust the brakes?

 

[dingbat]

If this were the case, why would you ever have to adjust the brakes?

You don't adjust disc brakes....

Drum brakes need adjusted because of the geometry. The bottom of the shoes pivot on a fixed point, in effect creating a heart shape.

The cylinder push the tops out to accommodate for wear but the bottoms are at the mercy of the auto adjusters that rust and become inoperable over time.
Most "maintence" adjustments are the result of the "failures".

Went to disc years ago to get away from the problem associated with drum brakes in a marine environment

In response to your travel comment, "not touching" is anything greater than 0 clearance. Your actuator should have no problem moving the wheel cylinder 1/32"-1/16" or so.

 

[bruceb58]

Tighten the tension adjuster... maybe 2 turns.
Try it.
If its better but not cured, do another turn.

Out of curiosity, what tension adjustment are you referring to? Never seen a tension adjustment on brake actuators that I have owned which have mainly been TitanDico

 

[bruceb58]

No, I have not pulled the drums since this started happening! How can this simple rebuild be a crap shoot? There is nothing in there except a spring rubber, and dust boot?

And piston. I assume you are honing the bore before you put the cylinder back together?

 

[Mellisa7]

I do not have "auto-adjusters"

 

[bruceb58]

Sent you a PM on where to buy the aluminum wheel cylinders.