bad brake fluid leak

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Mitch Covington
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Re: bad brake fluid leak

#31 Post by Mitch Covington »

Mitch Covington
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Mitch Covington
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Re: bad brake fluid leak

#32 Post by Mitch Covington »

sigh... and then from the same page... 2 different cap sizes.
Motive brake bleeder 2.JPG
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Re: bad brake fluid leak

#33 Post by Mitch Covington »

Ordered this one...
Motive brake bleeder 3.JPG
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Greg Scallon
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Re: bad brake fluid leak

#34 Post by Greg Scallon »

Yea. That's the one I have. I believe I bought mine from Zims, to insure I had the right cap. I hook up the cap to the fluid reservoir and then simply pressurize the fluid reservoir to about 7 lbs I believe. Then just crack the bleeders open one by one in the correct order until the fluid runs with no bubbles. Be sure to keep the fluid chamber topped off in between so it doesn't empty out.

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Mitch Covington
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Re: bad brake fluid leak

#35 Post by Mitch Covington »

I should have done it to start with since this is not the original MC, but I went and measured the cap, and it's evidently a VW reservoir with a 27mm cap. Got lucky, canceled the original order (Amazon) on time and got the right one. I much prefer to support our 356 vendors, but will get this by Sunday...Amazon is hard to beat in that respect. This one almost $20 more... go figure.
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Martin Benade
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Re: bad brake fluid leak

#36 Post by Martin Benade »

I have definitely supported monopolies that I didn’t much approve of because they were very good at what they did.
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Mitch Covington
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Re: bad brake fluid leak

#37 Post by Mitch Covington »

The new cylinder installation went OK, though I had a hard time getting the bottom fitting lined up enough to get it started. Finally figured out to undo the other end first. I bled all of the lines with the pressure bleeder and it seemed to work well, though after I finished the pedal was very mushy though the car stopped OK. I figured that I'd bleed it again later, and maybe adjust the pads. It was 2-3 weeks before I went to drive it again and by then I had a full, hard pedal! Just sitting seemed to fix it. That's the good news... the bad news is that today, several weeks later, it has TOO much pedal and the brakes are grabbing prematurely... the car stops before it should when on a slow roll. What's going on here? Is it the fluid? Prestone DOT 4 Synthetic (pic below)... I guess I just need to take off the floor board and adjust the play on the rod?

New Mast Cyl 2.jpeg
Brake fluid.jpeg
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Dave Erickson
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Re: bad brake fluid leak

#38 Post by Dave Erickson »

Did you replace all the rubber hoses?

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Mitch Covington
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Re: bad brake fluid leak

#39 Post by Mitch Covington »

I did not... but glad to know that's a potential reason for this. I'm trying to imagine how old hoses cause a increasingly stiff pedal... would you mind? Thanks in advance!
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Martin Benade
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Re: bad brake fluid leak

#40 Post by Martin Benade »

They can act like a check valve, holding that wheel’s brake applied (and dragging). And then the pedal is harder because the shoe/pad doesn’t need to be moved into contact, it’s already there.
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Re: bad brake fluid leak

#41 Post by Mitch Covington »

Understood, thanks! Will order new ones today.
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Re: bad brake fluid leak

#42 Post by Mitch Covington »

Can I assume the stainless steel braided lines are better?
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Wes Bender
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Re: bad brake fluid leak

#43 Post by Wes Bender »

No. They shouldn't be used on a road car. The rubber hoses fail gradually. The braided stainless hoses fail suddenly, as in total brake loss because one breaks. Buy the rubber hoses.
Some days it's just not worth chewing through the restraints.....

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Mitch Covington
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Re: bad brake fluid leak

#44 Post by Mitch Covington »

Great, thanks! Was about to hit the check out button! Saved me.
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Re: bad brake fluid leak

#45 Post by Doug McDonnell »

I think you should check to make sure there is the required 1mm space in your brake pedal rod. viewtopic.php?p=420833&hilit=brake+pedal+rod#p420833
1965 356C 2000 BMW 740i Sport 1967 Honda CL77 There is never enough time to do it right, but always enough time to do it over.

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