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Master Cylinder problem?

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jlaird said:
Jacks trickie trick. Get a short peice of pipe or tube or. slice it lengthwise on one side. Back off the adjusting nut just inside the tranny tunnel, slip your new spacer over the cable, retighten the nut untill you have the brakes adjusted properly.

About half inch would be about the right length I should think.

Gota think outside the box on some of this stuff.
Click to expand...

I'll look into that. This is to address a stretched cable or something? When adjusted it wouldn't really effect the hydraulics though would it?
 
The emer, brake should be loose. Backed off when installing the brakes. Then after adjusting the brakes it should be adjusted then bleed the brakes with the emer brake off. Now forget it till next time you need to adjust the emer brake a bit.
 
Yep, that's what I did. I wondered why, with new shoes (I didn't measure the drums) that I had to adjust so far on the e brake cable. It grabs okay and is nice and tight by 5 clicks so I guess that's serviceable. Puzzles me about the "squirty" MC yet though. PO had regular metal cap with a tiny hole punched in it on the MC, I got a new plastic one from VB on it now. It did not do this when I got the car, but started after first MC rebuild, and now I went through it again and it still does it.
 
Does your plastic cap have the gasket in it?
 
jlaird said:
then bleed the brakes with the emer brake off. Now forget it till next time you need to adjust the emer brake a bit.
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think that might be why I'm not getting anywhere bleeding my brakes :blush: of course as soon as you said it it was obvious - thanks
 
Oh, John-Peter, wish I had said something before.
 
why would you? - like I said it's obvious - besides I've only bled the brakes twice so far - needs to be at least three more times to match how often I've done everything else - thanks for mentioning it at all.
 
jlaird said:
Does your plastic cap have the gasket in it?
Click to expand...
VB doesn't show a separate gasket, Moss does. I remember seeing "no gasket needed" somewhere from VB, maybe when I ordered she said that. I suppose I can make one for it anyway, I assume it sits on the top of the threaded inlet or is it around the base? (see picture) Seemed to me the juice was coming right out the tiny vent hole but I'll double check tonight when I can get a pedal pusher to help me.
mcgasket.jpg
 
On top of the threaded inlet. Up in the cap. Moss sells one even.

And yes it is necessary unless you want brake fluid all over.

While doing that check that the pot metal part of the MC is very smooth where the gasket will fit. use sand paper. Also where it fits to the cast iron body. Use sand paper on a peice of glass.

Oh yea remove the pot metal part first so you can clean any sand from the paper off real well.
 
The lower gasket in your diagram is not necessary, but being made of felt (you could cut one out of a piece of heavy felt yourself!), it does absorb over-spills nicely when filling the MC!
 
I found a rubber gasket that fit nicely, confirmed it is coming out of the vent hole, either brake or clutch, same. Not overfilled. Odd. I'm going to try to temporarily plug the vent and see. Why vented? Let air in if fluid drops? Curious as it lets moisture in too then and that's hard on brake fluid and thus parts over time, no? I can see fluid "squirting around" when pushing pedals with the cap off, hard to believe it can make it's way out the little vent but it is.
Could it be the guy who rebuilt the MC did something silly with seals or piston position? (that guy is me BTW). This is such a simple MC it's hard to get much wrong! The fact that both clutch and brake give the same result is really odd too, maybe one side has a mistake in it, but both?

PS pulled the gasket out of a brake fluid can's cap, stuffed it in the MC cap (covering the vent hole). Pushed pedal(s) repeatedly, no seepage. I'll leave it like that for now I guess.
 
Finally pulled the MC apart (snow started to fly). I want to put bleeders in the outlets so I can bench test it but I don't know what would work. Does anyone know the proper name for the size and type bleeder valve to fit the MC? Nothing I have laying around will both thread in and seal. Don't want to bunge up the threads either!
 
Well I used my thumb to plug the outlet for now. Swapped main seals from the clutch side to the brake just to see what effect it'd have. Before I swapped the brake side would squirt out the smaller more rearward hole in the resevoire, and if I really shoved the piston in (by hand) it would squirt out with gusto, now it just gurgles a little, so I guess that seal just wasn't good enough (it was a generic 3/4 cup seal from NAPA).

PS
What color should the pedal arms be? Since it's all apart...again, and it's winter, I think I'll paint things that I mess with. Will paint the pedal box, pedal arms and such. Just rattle can and nothing fancy. Brake fluid will destroy it anyway sooner or later.
 
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