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MG MGB Technical - Master cylinder?

I'm looking to buy an 80 MGB rdstr that has been sitting for 10 years in a garage.
The clutch is not working. The fluid is topped off, so I attempted to bleed a nice looking slave. Doesn't appear to have been driven on the road. (Not dirty)
First 10 strokes produced fluid streams. After that, depressing the pedal produced no fluid from the slave. The fluid level is okay in the master.
What is the best guess scenario? Bad master? Bad slave? Both?
It's possible someone put the slave on and didn't bleed it correctly.
Cleve Crews

What did the pedal feel like? If it was floppy, i'd guess a bad master is letting fluid past the seal. If it was hard i'd suspect the flexi has closed internally due to deterioration.
The slave is also possibly a culprit. Gently prise off the boot around the actuation pin and see if liquid comes out. If it does, it's a bad slave too. You can also do a similar test on the master, but you'll have to remove the pedal box cover. You could also check for fluid running down the pedal itself pointing to a bad master.
The new slaves that are sold these days often come with the bleed nipple in the inlet port for the flexi pipe (to save space in packing I guess). While this makes it basically impossible to bleed all the air out if you somehow manage to put it on the car like this, it shouldn't stop fluid coming out at least a little bit.
Roadwarrior

I'm looking at the car again and this time I brought a mityvac to see if I can bleed the clutch.
Suction on the slave produces no fluid. Fluid is topped off.
?
Cleve Crews

Also, pedal is weak like just the spring pressure.
Cleve Crews

My money is on a faulty master cylinder. It sounds like its inner seals have perished and are allowing the hydraulic fluid to bypass them when you press the pedal to the floor. A very common problem with a full master cylinder that doesn't function. RAY
rjm RAY

Thanks Ray!
I'm going to take it home on a trailer tonight. I also found out it is a 79, built 3-1979. It's got the dealer sticker on the back from where I worked from 78-81. That's another plus for a one owner car. I might have a picture of this car new, or one just like it. All of ours had dealer installed stripes, and they were all variations of the same theme, but slightly different.
The license tag on this car is from 1992. 23 years old!
Cleve Crews

If the fluid level didn't drop in the reservoir when you were pumping fluid out of the master then I'd say the bypass hole into the cylinder was blocked. Especially if suction at the slave produces no fluid when the reservoir is full.
Paul Hunt

Paul,
That's the case. Looks like it is getting replaced soon.
Cleve Crews

This thread was discussed between 07/03/2015 and 09/03/2015

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