I've got vacuum assisted hydraulic brakes on a 1886 Grand Villa tag axle on a P 30 chassis. The vacuum line is sucking air from either the check valve or booster diaphram. Does anyone know anything about these parts ? Manufacturer ? Source or service?
Wantabe
Sounds like booster is broken. Disconnect it and plug the hose and see if it runs better. Try the brakes very carefully.
I would imagine the booster would be available from NAPA, most likely as a rebuilt it will come with the check valve. Also check the hose good, over time they will get soft or develop leaks especially at the intake manifold.