Brake pedal slow return

[mlktst]

OK I have a 67 charger wilwood front disc, drum rear manual NOT power double reservoir master cylinder [unknown brand]. No proportion valve. Bought as is driven 6-7 thousand miles just fine. Now my brake pedal is very slow to return to top, brake lights stay on, brakes seem to drag. can lift with foot and it stays at top. Is master cylinder going out ?Fluid is full and clean. hmmmmmm Thanks in advance

 

[PurpleBeeper]

From what I know, the brake light stays on when there's a pressure difference between the front/rear brakes (assuming, & you should check this, that the parking brake switch isn't activated/grounded). It sure sounds like your master cylinder has gone bad. I think you should also check for a leak too just to be sure.

Master cylinders are cheap & easy to replace..... and brakes going out unexpectedly is really bad (ask me how I know)

 

[mlktst]

From what I know, the brake light stays on when there's a pressure difference between the front/rear brakes (assuming, & you should check this, that the parking brake switch isn't activated/grounded). It sure sounds like your master cylinder has gone bad. I think you should also check for a leak too just to be sure.

Master cylinders are cheap & easy to replace..... and brakes going out unexpectedly is really bad (ask me how I know)

Yep PurpleBeeper that is what I was thinking just needed to hear it from an adult I am only58. Pulled rear wheels to check for leaks clean and dry, I just used flashlight to check for leaks in front calipers. Can't find leak time to get off my posterior and swap master cylinder, thanks

 

[NJRR]

Yep PurpleBeeper that is what I was thinking just needed to hear it from an adult I am only58. Pulled rear wheels to check for leaks clean and dry, I just used flashlight to check for leaks in front calipers. Can't find leak time to get off my posterior and swap master cylinder, thanks

Don't forget to bench bleed the new one !!!

 

[mlktst]

Looking close I have a drum to drum master cylinder, working or not probably not It is the wrong part. I ordered a disc to drum master cylinder from Ram Man inc that should fix issue. Yep NJRR will definitely take the time to bench bleed, I am way too lazy to do things twice haha THANKS AND BEEP BEEP

 

[oldbee]

Don't forget to check bushings at brk pedal pivot either, just a thought.

 

[The Rebel]

Any chance it's a vacuum leak?

 

[mlktst]

Yep oldbee checked bushing for end to end and slop checked brake rod pivot bolt. Bushing good pivot points oiled and smooth Rebel i have manual brakes no vacuum line. I am not a gambler but willing to bet up to but not over 50 cents a proper master cylinder will fix it, will find out soon. Previous owner never drove car I drive 2-3 times a week couple of irritating things to fix but great driver

 

[oldbee]

Just trying to get ur brain-pan thinking of all choices. It popped into mine all of a sudden.

 

[5.7 hemi]

The internal spring on the mc is toast. A new mc will fix ya right up.

 

[69L48Z27]

If you had drum/drum the brakes will drag, they have risudual valves in the port for the front brakes. Disk/drum will make that go away.

 

[mlktst]

Decided on Dr Diff 15/16 bore master cylinder. Did bench bleed install then system bleed. Very nice unit aluminum new, not rebuild. Install was simple everything fit and worked, don't get much better than that. will post brake test later THANKS

 

[Billccm]

I have the same master cylinder. LONG pedal travel, but it STOPS! I like it.