adjusting brakes

[olgraybeard]

on a pw-b2 I thought I read there was a "window" in the backing plate so you could see the gap between the shoes and the drum, did I read wrong, I can't find it. Also do the adjusters turn the same direction to tighten the shoes or opposite directions

[Gordon Maney]

on a pw-b2 I thought I read there was a "window" in the backing plate so you could see the gap between the shoes and the drum, did I read wrong, I can't find it. Also do the adjusters turn the same direction to tighten the shoes or opposite directions

There are no adjusting slots. The adjusters present as hexagonally shaped features, two at the top and two at the bottom. The tops can be turned with a wrench. The bottoms have lock nuts that must be loosened prior to turning.

All four are adjusted at time of initial shoe installation. Subsequent adjustments are performed with just the top adjusters.

Upper and lower are both eccentrics, though they differ in their design.

Is this an old install you are now choosing to adjust?

[olgraybeard]

This is a old install when I got the truck it had almost no brakes I replaced the master cylinder and bleed the brakes, I'd say its got about 3/4 brakes now I think a adjustment all around will improve the brakes. I have 2 adjusters at the bottom and a little less then 3/4 up on the side are 2 more adjusters that are a little different, that I thought were adjusting side ways motion on the shoes are those the 2 that you are talking about. There are no adjusting bolts at the top of the backing plate. If these are the ones you are talking about do the move clockwise or counterclockwise to move the shoes twoards the drum.

[Gordon Maney]

Yes, those are the ones.

As viewed in your photo, that one will turn counterclockwise to tighten. The other will turn clockwise to tighten.

Someday when you have a drum off you will see the simplicity of the design.

[olgraybeard]

Thanks, I'm try not to pull drums right now not enought room to pull axles. On my way to do it right now

[Gordon Maney]

You don't have to remove axle shafts to remove drums. The drums come off the hubs. The drums are retained by three, flat head screws. There are tapped holes for puller bolts in the drums.

Keep the drums with their respective hubs.

[olgraybeard]

all but one adjusted most were pretty close may be 1/16th of a turn. the one I'm having problems with I'll have to pull the drum I can move it 4 full turns either way without the shoes making contact (maybe no shoes in that drum or the linings are gone?) brakes are better though.

[Tom Petroff]

all but one adjusted most were pretty close may be 1/16th of a turn. the one I'm having problems with I'll have to pull the drum I can move it 4 full turns either way without the shoes making contact (maybe no shoes in that drum or the linings are gone?) brakes are better though.

The bolt stud is most likely spinning in the cam, It was a swedge fit.
After you get the drum off you can tack weld it.

The Adjusting window is on the front side of the drum. Tire/wheel must be removed to see it.

It was for the use of a feeler gauge.You can see a little of the lining.
There should be a small plate with a screw over the window.

If you pull a wheel use a .008 in. feeler gauge and see if you can get in between the drum and shoes all the way around. That tells you if the shoes are properly centered.

The proper clearance is .006 at the heel,and .012 at the toe of the shoes.

I use .008 to .010 all the way around. Gets me close enough.

If you can't, that's when you adj. the bottom cams. Once that's done you only adj. the top as Gordon said.

Your doing right by forgetting the window and adjusting for light drag on the shoe.

Best reading here at Paul's Cook's site. Best description on the web.

http://www.texaspowerwagon.com/Brakes.htm

[olgraybeard]

thanks now I know what to look for which always saves time!!

[Gordon Maney]

In practical terms, most people are afraid to put enough drag into the initial adjustment.

One additional benefit to familiarity with the adjusters can come into play during brake bleeding. A good initial bleed can be best implemented by turning the upper adjusters clear out, locking both shoes to the drum. This prevents wasting any master cylinder stroke on shoe movement during pressure buildup.

It is a necessity when you bleed something long like a school bus or long straight truck.