i have a 1987 P31 workhorse frame w a 31 Dolphin body . now the question how to adjust the brake at the drum not at the handle . i pulled the drum off most of the way and the shoes are good but i cant figure out how to ? hints ???

I think what you must have is a GM, P-30 chassis? If so you have the standard GM truck brake system and while I'm not a mechanic, I would think that someone here will be.

As old as that chassis, and from your post, apparently it just has ordinary drum brakes. Those have a self adjuster coupled with the star wheel adjuster between the shoes at the bottom. The self adjuster just pushes down on the side of the star wheel nearest the drum causing it to tighten. The self adjuster is supposed to work when the brakes are applied while backing up.

The brakes are supposed to be manually adjusted by putting a tool shaped like a bent screwdriver into the slot in the backing plate by the star wheel. Tightening the brakes manually requires turning the star wheel up since the autoadjuster pushes the other side of the star wheel down. There is supposed to be a rubber plug in the slot. BE CAREFUL WHEN ADJUSTING. IF YOU MAKE THEM TOO TIGHT, THE SELF ADJUSTER STOPS YOU FROM BACKING UP THE STAR WHEEL. Backing off requires pushing a second tool into the slot to push the self adjuster away from the star wheel while turning the star wheel down with the adjusting tool. That can be a pain, not to mention the busted knuckles.

got it thanks yes it can be a pain but the other result is it rolls if im on the ferry or on a slight incline and crush a small car or person behind me .. thanks to all

Jim, were you talking about the drum brake mounted on the drive shaft?

Your problem might be what happened to this motorhome.

I have one of those drive shaft emergency brakes on my 1996 unit. It comes with the rear disk brakes on the "modern" chassis. From his description and the age of the unit I concluded that it was not the drive shaft brake. I had the rear drum brake system on my 1985 unit and I wish I had it now. I don't trust the drive shaft brake. It is no better than park on the transmission. The rear drum brakes last a bunch longer because they don't drag.

yup it is the park brake that is a drum brake on the drive line . after i have had a look i noticed that the shoes havent arced to match the drum. i think ill take a 1/2 hour and drag the brake a bit to try to shape it then check it . this way ill get better contact when i engage the brake.. and not have a rv in the lake happening to me

Keep in mind the issue of heat, that drum is going to get pretty hot dragging as it spins a lot faster than a wheel drum at the same speed.

Our IH had a similar brake and once we found all the adjustment points it was pretty easy to deal with and worked well.

Also, getting it to "seat" properly like this may glaze the surfaces making it have even less friction than it now does.

If the brake shoes arc does not match the drum, yo may try using it to stop you a few times in safe conditions and low speed. But first, I would try to make sure that the pivot adjustments are correctly set so that the shoes can actually come in proper alignment to the drum surface when it mates. Does not take much of an offset in the pivot to make it mismatch.

yup just doing a few slow stops is all im planning to do . be doing a roll and a gentle application of the park brake with no throttle being added at the time. nice and easy for this . the brake works smooth and easy. thanks to all.