Did I buy the wrong master cylinder?

[TheRealDavid]

I just went through that with an Orieleys MC. https://www.oreillyauto.com/detail/...r-cylinder-new/ohh0/nmc11218?q=NMC11218&pos=0
This master cylinder fit perfect and the fitting's screwed in easy but I kept getting a drip on the line for the rear brakes. I cut the line and reflared (double) the flare but it still leaked. I removed the MC and looking in the ports I could see that one seat had a clear impression of where the line sealed against it and the one that was leaking had no impression at all. One odd thing about this MC is that the seat was not the usual brass seat but was aluminum(?) cast in when the aluminum cyl was cast. and the seat was NOT smooth or machined at all. I took the cyl back and they exchanged it only to discover the new one leaked too!!! I then decided that the threads were not cut deep enough and wouldn't allow the seat to seal. I decided that they should not be hard to cut deeper, since it was aluminum. Now you can't us a regular tap as there is a cast in seat in center of the fitting hole so I took the line off of the car and cut four slots in the fitting such as you would see a self tapping screw. I reinstalled it, put a little cutting oil on the threads and tightend it down, TIGHT, then I tightend it some more, backed it out and tightened it down 1/ 4 turn more. Bled them out and NO LEAKS!!! Been working fine since March!

@Longknife holy molé that is exactly what is happening with mine. shaking my head.

 

[1 Wild R/T]

Hell.. It's only your brakes... Not like it's a safety concern or anything.... Wait... What??

A couple years ago I attempted to get a car that hadn't run in years back on the road... Three bad Master Cylinders, Two were assembled wrong, one was missing a seal all together... I wound up fixing one of the ones that was assembled wrong... Quality? What's that?
When I worked for Ford they were pushing "Quality is Job 1!!!" I would always reply, "No Paycheck is Job 1!!".. But we certainly tried harder than the current parts supply chain does....

 

[Billccm]

Hell.. It's only your brakes... Not like it's a safety concern or anything.... Wait... What??

A couple years ago I attempted to get a car that hadn't run in years back on the road... Three bad Master Cylinders, Two were assembled wrong, one was missing a seal all together... I wound up fixing one of the ones that was assembled wrong... Quality? What's that?
When I worked for Ford they were pushing "Quality is Job 1!!!" I would always reply, "No Paycheck is Job 1!!".. But we certainly tried harder than the current parts supply chain does....

Simply too much Chinesium in use today.