C3 brake light issue
Thread Starter
3rd Gear
Joined: Jul 2015
Posts: 3
Likes: 0
C3 brake light issue
alright so my C3 I'm partially restoring has left me with another problem. Its a 1977 350 with th350 tyranny. when I press on my brake petal while not in gear everything is fine. but when i put it in drive and fully press the brake pettal going a decent neighborhood speed, the brake light comes on. when it comes on i feel a click and the petal travels to the floor further than it normally would and my braking power is reduced. the weird thing is, next time i stop, i feel a click again and the light turns off and full braking power is restored. It intermittently comes on after every other brake petal.
I think what causing this is the brake proportioning valve (i think its called that for this year) is shifting over and blocking off either my rear or front lines. The question I am asking is what would be the most economical way to fix this. I could always replace the lines, calipers, master cylinder and proportioning valve all at once and it would probably fix the problem. But i don't want to spend excess money if i dont have to. my current mindset is to replace all the calipers with the rebuilt "o-ring" style calipers and see if my problems are fixed. Any insight would be appreciated. I still daily drive this so even when the light is on the brakes still work.
Thanks
I think what causing this is the brake proportioning valve (i think its called that for this year) is shifting over and blocking off either my rear or front lines. The question I am asking is what would be the most economical way to fix this. I could always replace the lines, calipers, master cylinder and proportioning valve all at once and it would probably fix the problem. But i don't want to spend excess money if i dont have to. my current mindset is to replace all the calipers with the rebuilt "o-ring" style calipers and see if my problems are fixed. Any insight would be appreciated. I still daily drive this so even when the light is on the brakes still work.
Thanks
Team Owner
Joined: Jul 2006
Posts: 22,197
Likes: 4,182
From: Kannapolis NC
Without knowing what you've tried, the very first thing I'd do is bleed completely all four calipers, keeping the m/c full and try again. If it works a while and then has to be bled again, you may be pulling air into one or more of the calipers due to seals or runout.
