Packard Forum Index » V-8 (1955-56)

My 55 Caribbean has a noisy treadle vac. When I step on the brake pedal with vacuum in the system it makes a noise that I will describe as a burp. Every time you push the petal, it burps. The car stops normally. If I turn off the engine and pump the petal, it makes the noise until the vacuum is depleted then disappears. I'm thinking maybe something in the vacuum portion of the brake. Ant ideas?

I think it's the vacuum check valve at the base of the carb. The vacuum hose connects to it. When it's off the car and you blow through it, it makes that noise. Put an a Tums in it and call me in the morning

It might be the check valve but since it still does it when you are using what is in the reserve canister I wonder. The check valve should remain tightly closed when the engine is not running and there is no manifold vacuum to pull it open.

I would wonder if one of the poppet valves in the booster section is acting up and not opening or closing smoothly.