Master Cylinder question

[Daniel Romero]

Hey all,

Just a quick question. Anyone ever have any issues with aftermarket master cylinders not working like they should? I have a friend telling me that they're known for being troublesome and not providing adequate pressure or something to that effect. Any recommendations on any parts stores you all have had success with?

 

[kenmdale]

I went through 3 of them from different suppliers
Before I found one that didn't leak
Ken

 

[3C's & a D?]

I went through 3 of them from different suppliers
Before I found one that didn't leak
Ken

A brand new? Or rebuilt? Master that leaks, not to sound too questioning, but where exactly is it leaking?

 

[cantflip]

There are only 2 places to leak. Externally from the rear seal in the booster/bulk head... or internally bypassing the front cup seal.

External leaks are not uncommon, and for as long as some of our parts may have sat around... a little rust or a dried up seal could be the cause.

Internal leaks are more likely a flaw in your bleeding practices. Never let the pedal go all the way to the floor when bleeding, many master cylinders do not have a finished bore all the way to the end and will damage the front cup seal if you do.

Daniel, to better answer your pressure concerns. Hydraulic pressure is created by piston diameter differences. If any hydraulic component is changed to one with a different diameter... it may bolt up and seem fine, but won't create the same force.

I would be very cautious of incorrect parts, the evolution of part people and the transition to electronic catalogues has lost a lot of important information. I once had a full aftermarket catalog set from the late 80's from a parts store I had updated the catalog racks in. I wish I still had them every time I go searching for old parts. Not only did they contain detailed information that is often lacking in the electronic systems, but the well used ones would contain handwritten notes from the Jobbers who used them and found errors or other critical information items.

 

[kenmdale]

in my three cases , all leaked at the booster side of the master cylinder.
this is what I remember from last summer. It is difficult to remember anything, while lying in a hospital bed in the Cancer ward, after a bad second chemo run and 26 radiation visits

If anyone has holiday plans, DONT miss them, dont put things off (sorry if this comes off as whining, it was not meant that way )
cheers
KEN

 

[live4theking]

Ken,
I'll be praying for you.
John

 

[kenmdale]

cheers ,thank you