The Stovebolt Site Forums The Shop Area Driveline '41 YS brakes. What am I missing?

Replaced all four cylinders and all rubber hoses. Adjusted all pads according to the manual. Bled the system 3 times. Still pedal goes to the floor when pressed. Whats next?

Andy

Master Cylinder. Look for pits from rust.

Best to rebuild or replace

Its best to rebuild it if it doesn't have pits in the piston travel area that can't be honed out.

Update, Master cylinder was replaced, to many pits. Bled everything I think. Now have the issue of having to pump the brakes to get them to work. Is that a sign of air still in the system? If not, any ideas?

Thanks

Did you bench bleed the master cylinder? If you have the under floor master then look into 10 pound residual valves to hold pressure on the drums. Yes, it might be air but have you adjusted the shoes for a slight contact?

Master cylinder was bled per manufacturer instruction. Brakes were adjusted so the pads rub then backed off a few clicks. What is a residual valve and where do you find one?

Residual valve is a one way check valve. They are used inline with the brake lines to keep a certain pressure on the shoes or pads. In you case with all drums you need a 10 pounder (2pounds for disc). They are considered necessary for systems where the master cylinder can be below the brake cylinders. Fluid runs downhill so the fluid in your lines can run back into the master cylinder. They are usually located near the master cylinder. You will need one for all lines leaving the m.c.
They are around 1/2" in diameter and about 2" long with tube connections on the ends. Cost around 8 to 10 bucks.

So it keeps 2lbs of pressure on each cylinder. Sounds good
Thanks

2 pounds for disc and 10 pounds for drums.

Usually if you can get a solid pedal on the second pump, it is an adjustment problem. I would adjust the shoes so that they are tight and then back off to where there is still some drag.