Master Cylinders

[nodemon]

How can you tell if a master cylinder needs to be honed..? Do you hone every time you rebuild one..? Mine is leaking out the back.

 

[Demonracer]

Depending upon how bad it is leaking, I would say replace it for peace of mind. I've never relied on rebuild kits because the brake fluid causes pits in the bore and they never seem to seal up well.

 

[Murray]

Hone every time you rebuild. This usually works 90* of the time as most pitting doesn't occur where the seals ride. There are exceptions and they will leak despite all this and now you must replace the whole M/C. Replacement is the only guarantee of no leaks. If you must restore a M/C, then they can be sleeved.

 

[Bewy]

The problem with many m/cs is that are made out of Detroit's wonder metal: cast iron. Which rusts, especially once the brake fluid has absorbed moisture.
If you intend to keep the car, best bet is to have the m/c s/s lined. As the name suggests, the m/c is bored out & a s/s liner fitted. Lasts forever.