The Stovebolt Site Forums The Shop Area Driveline Brakes not working - looking for suggestions for a newbie

I took the rear fender off the bed and there was some banging going on to get the bolts out. Took off the rear wheel as well (including jacking it up to get wheel off).

The brakes worked prior to this process. Now the pedal goes all the way to the floor. Everything is so coated in rust and dirt, I wouldn't even know where to start to look for leaks, etc (plus my limited knowledge of drum brakes).

It is a 51-1 ton with drum brakes on all wheels.

Anyone have any ideas where to begin?

Thanks,
James

Hy J_Wade, everything fails eventually, but this failure probably has nothing to do with what you have been doing. First off check the master cylinder (under cab floor) to see if there is any fluid in it. You could also scoot around on your creeper under the truck and follow the brake lines checking for wet spots. We usually suggest a complete rebuild of the brake system for everyone's safety, new or rebuilt master cylinder and wheel cylinders, flexible and hard brake lines new brake return springs, linings and brake drums turned or new, you get the idea. Get back to us with what you find on your inspection.

If the rear wheel cylinders were raise above the master cylinder when you took the tires off, air could have entered the system at the wheel cylinders and all the fluid could run back to the master cylinder. If this did happen, one or both wheel cylinders are bad. If there is no sign of a over fill at the master cylinder, start following lines as already suggested till you find the leak. In this case, all the dust and dirt will work in your favor.

Joe

Thanks for the info! Yes, the rear wheel was raised above the master cylinder.

Going to be a stupid question but how do you check the master cylinder for fluid on this truck? I mean is there a fluid reservoir like on modern trucks or a fill hole somewhere? If there is no fluid, then I need to add fluid and then bleed the break system? If I need to add fluid, what kind of fluid does it need - regular brake fluid?

Re-man the rear brakes is on my list to do soon. I have been reading on how to perform it on this site. My concern is over knowing if the drum needs to be replaced and where to find parts.

Thanks,
James

There is a round rubber plug on the floor on the drivers side. Pull that plug up & the MC reservoir is under there. Fill it with fluid & pump it a few times. Use DOT 3 brake fluid. The pedal should pump up. Then like the guys said crawl around under the truck & look for wet areas. Watch the bottom of the brake backing plates for fluid running out which will indicate leaking wheel cyls.

Hy J_Wade, the master cylinder with built in reservoir is accessed through the cab floor on the drivers side, there should be a rubber plug in the floor which you have to pry out, and then you can remove the cap. The cap will probably be metal with either a square or hex head, they can be exceedingly tight especially if they have not been taken off for years, good luck.

Thanks. Will take a look at it tonight/tomorrow and post what I find.

Floor is almost completely rusted away so it should be easier to find the reservoir. Guess that is good and bad at this point.

Any suggestions on removing the drum? Gentle taps with a hammer?

Really appreciate the information you guys provide.

Thanks,
James

Checked it. Reservoir was bone dry. Filled it up and pumped the brake a few times. Brakes are very responsive now.

Looked under truck and found the rear passenger side drum looks wet on the back side. I think that is where the leak is as I couldn't find any others.

Thanks again for the info. I am sure I will have more questions once I start rebuilding the rear drums.

James

I don't know if you have a hard copy of the manual, but here's a link to it online if you need it for reference. 1948-1951 Shop Manual

Thanks for the reminder. Totally forgot about that manual.

Thanks,
James

Is there a source for new drums for 1-ton trucks?

I have not found one yet. Anyone else have any insight in to where to find new drums for 1-ton?

Check your local truck stop. The mechanics there may be able to recommend a shop reline your shoes.