Can anyone give us any tips for the bench bleeding of the master cylinder when installing disc brakes on a Model T. When I installed discs on my 26 I managed to get them working in an afternoon. now another club member has installed them on his 23 coupe and after several weeks of working on them, they still wont work. I feel that the problem is getting all the air out of the master cylinder, but need some guidance on the proper steps to use when bench bleeding the master cylinder. Ed
Make sure the plunger is pushed in all the way. If not, the brakes will feel spongy, and you will need repeated pushing to get any stopping power. To final bleed mine, I removed the connector that goes onto the brake pedal, and then fashioned a lever to push the rod in all they way. Without doing that, I doubt if you can ever get all the air out, short of removing the cylinder from the car and doing a traditional bench bleed.
I hope this helps.
See...this is what happens when there is an attempt to do something unnatural to the car that Henry would not do.
You may want to check to see if the master cylinder is not leaking or problem on rebuilding.
Eddy, with the layout of this system doing a reverse fill may solve the issue. That is the most efficient way to get the system filled with no air in the lines. You may be able to borrow/rent the equipment from an auto parts store. When you fill from the calipers, all the air is pushed up to the master cylinder and out as you fill the system with brake fluid.
Just be sure to bleed the top air vents, not the bottom vents
I ran into a similar problem when I put a Ruckstell under my 26 Roadster with SurStop brakes. The brake pedal rod was not getting a long enough stroke. There was a slight difference in the new axle so I had to lengthen the rod to get a full stroke. Works great again.
Thanks for your responses. I believe we're going to try the reverse bleeding next week. Ed
Eddy; When I did mine,before I linked the master cylinder to the brake pedal I used a long screw driver as a lever to get full travel of the master cylinder to bleed the cylinder and the lines. I had to rotate the wheel cylinders to get a bleed fitting at the top to get the last bit of air out.Once done, the pedal only moves about an inch and is very firm. Brad from New Hampshire.