Stiff Brake Pedal??

[SC74]

I have non-power disc brakes. I have never upgraded to power brakes since the pedal has been so light. I do have a Corvette master cylinder, but do not know if that is related to the light pedal.

Now my pedal is VERY stiff. It's like it happened over night. What could cause this? Now I'm looking to possibly bite the bullet and add a booster.

Thank you for the help!

Robert

 

[surfer-b]

Are all the wheels free, does it seem to be pulling to one side, is one of the rear wheels locking up before the other. Sounds if the m-cylinder or p-valve is clogged or one of the lines kinked, something not allowing fluid to flow to the wheel cylinder. can't be much-not many parts envolved.

 

[pinenuts]

I will be following this thread as I have always had this problem. I have a 76 with un-boosted front disk brakes. It is hard to believe that Ford actually put disk brakes on these trucks and made the power booster optional. I have had my truck for eight years and my right leg is twice the size of the left from trying to stop this beast. I am planing to add a booster soon.

 

[SC74]

Are all the wheels free, does it seem to be pulling to one side, is one of the rear wheels locking up before the other. Sounds if the m-cylinder or p-valve is clogged or one of the lines kinked, something not allowing fluid to flow to the wheel cylinder. can't be much-not many parts envolved.

Does not pull to either side - drives fine, just a stiffer pedal. I haven't had time to look any deeper into it, but plan on searching for the problem tonight. Any tricks or advice on how to check the master cylinder?

 

[surfer-b]

dirty fluid will cause stiff pedal, HA doesn't sound approp for this site, but true, when was the last time the system was completely flushed, open the m-cylinder, is the fluid clean-clear or is it murky if so remove the all the fluid in the cylinder take a clean rag and clean the bottom out good replace with fluid and bleed all the cylinders until clean fluid comes through this will make a huge diff.