Replaced the master cylinder, and bled the brakes. However, we didn't use a hose to drain the fluid, is this necessary or can you just let the fluid spit out?

The car doesn't stop all that well and the brakes are rather mushy. The brake light came on for a few minutes but went away after we re-bled one side.

 

Did you bleed the master cylinder? You have to bench bleed the master cylinder if its been replaced or has air in it...

 

what's bench bleeding lol, I think that might be the problem them, I just switched it out and then did the brakes.

 

I think the most effective way to do our type of master is by making 2 brake lines that connect into the output ports on the MC, and then curve up into the reservore. Fill the reservore about half way with brake fluid making sure the 2 lines are submerged in it. Then use a dowel to slowly press in the adjusting rod on the master. You should see air bubbles rise thru the fluid, then when you release the rod it will suck fresh fluid back into the primary and secondary ports. Keep repeating until no more air bubbles come out. Then install the master, bleed the brakes, and call it a day.

 

Here's a quick doodle

 

Sounds like you got air bubbles in your brake lines Mark.

 

You will need to bleed the entire system again if you didn't do the bore of the master cylinder first. I will list the step by step instructions of bleeding the bore for you later, I don't have my Haynes Manual with me right now. But, I can tell you that you don't have to build any contraptions as mentioned above. I just did it this weekend and it's real easy.

 

If you bleed the brakes without bench bleeding the master cylinder, the air that was in the master is now down stream in the brake lines. Even though you may not be getting air at the brake bleeders right now, there is still air in the system.
I would say rather than taking off the brake lines at the master to bench bleed it (Which at this point won't help you), just keep bleeding the brakes. It may take a while but you will get more air out of the lines.

 

I would still bleed the bore if I were you. It only takes a few minutes and it guarantee's their is no air stuck in the bore.

 

Okay, as promised here it is -

To bleed the master cylinder bore -
1. Remove the vacuum reserve from the brake power booster by applying the brake several times with the engine off
2. Be sure to check brake fluid levels periodically through the bleeding process (don't want more air in your lines)
3. Disconnect the forward brake line from the master cylinder bore until brake fluid begins to flow out, then reconnect the line.
4. Have an assistant depress the brake pedal very slowly (one time only) and hold it down.
5. Loosen the forward brake line at the master cylinder to purge the air from the bore, retighten the connection, then have the brake pedal slowly released.
6. Wait 15 seconds (Important)
7. Repeat the sequence, including the 15 second wait, until all air is removed from the bore.
8. After the forward port has been completely purged of air, bleed the rear port in the same manner.
9. Next you will need to bleed each individual wheel in this order. (Important) Back Right, Back Left, Front Right, Front Left.

If you follow this procedure as listed I guarantee you won't have any more air in your lines. I actually did this last weekend, so I know it works well.

 

That is the on the car method. The most thorough method is off the car using the lines I posted above. Both will work, but bench bleeding is the best way to do it.

But as it was mentioned, you will have to redo the bleeding on the car to move all the air out that the master passed thru the lines.

 

bench bleeding is best, especially since you can't just keep bleeding them at the wheels to get the air out, since the master is the highest point in the system, so they get trapped in the master. I like onebinky's setup for a cheap method. also, that's why the phenix injector works so well, it works on the air rises in fluid prinicple.

 

What's a phoenix injector do?

Oh, there's also a syringe method for bench bleeding, but I don't remember exactly how to do it off the top of my head. Supposed to be pretty effective at getting it all out too.

 

the phoenix injector injects fluid from the bleeder valves up to the master cylinder, pushing the air bubbles up into the master cylinder. you can use it to bench bleed too, pretty similar to your method of using 2 lines bent back into the resevoir.