Brake trouble on "76 Dodge motorhome

[Big Dave2]

I have a '76 dodge Jamboree class c. I owned this unit for a couple of years and then sold it to my sister. She didn't want it any more after about 2 years so I bought it back from her.

When I first owned it the brakes worked fine. Now when I got it back they are not there at all unless you really put a lot of force down on the pedal. I checked the brake fluid res. and it was very low. I added fluid but this did nothing.

How do I know if there is just a leak and now the brake lines need to be bled, or if it is the master cylinder that is bad? Is there any easy way to tell? If not what step would you take next?

[sparcebag]

Pump the brake peddle get pressure on it and hold it if the peddle goes further down as your holding it your losing pressure,go under and look for leaks.no leaks bleed brakes and try it again.if it yet goes down it may be your master or one of the wheel cylinders.you'll see a wheel cylinder leaking easily.If they arent leaking redo the master.

[theoilman]

To check your power booster: First with the engine shut off pump the brake pedal several times to use any reserve boost. Then press and hold pressure on the brake pedal, while holding down on the brake pedal crank the engine. If the booster is working is working properly the pedal should go further toward the floor, probably half way.

This test will probably not work or work accurately on newer vehicles, but your 76 it should give an good test of the power booster.

The test in the post above about the master cylinder and holding a steady pedal level while holding pressure on it will most of the time reveal a leaking master cylinder - if the pedal falls away here without loosing brake fluid usually the master cylinder is bypassing - and the fluid returns to the reservoir.

If you are loosing fluid you probably have wheel cylinder problem (one or more wheels). If wheel cylinder problem I recommend replacing with new ones rather than rebuilding.

Or, how much has it been driven in the winter? Salt corrosion does eat through the brake lines too.

[Jeremy airjer W]

So the pedal is at the normal position and its just hard to push down?

Maybe its a vacumm leak to the brake booster?