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Discussion Starter #1 (Edited)
'71 spider-- hasn't moved since '89. I am assuming i will end up rebuilding all the calipers but really wanted to know what else may need it as well. The pedal was rock hard. BAcked off the nuts on the MS and pedal moved. Pulled MS and was able to easily move it by hand. drained & cleaned MS and reinstalled. was abled to get pressure to rear brakes so I bleed them. Very dirty. Looked like Coke. Now for fronts. Cannot get any fluid to fronts at all. Disconnect brake line at MS and MS works perfectly. Disconnect brake line at disc and get nothing. Can a brake line get clogged? I have never seen this but i must admit I have only worked on one other car that was dead for this long. At this point I will try anything. They say never introduce air into a brake line but i am considering trying to blow them out. Any ideas?
 

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It's possible the soft lines up front have gone to crap and collapsed or gotten goo plugged.

You might try uncoupling where the soft line connects to the hardline, then checking the MS again for flow/function. (if nothing else, it'll give you a good enough reason to flush or replace the hardlines)

The soft lines should prolly be swapped as a matter of course by this stage as they've been sitting for an awful long time unused and I for one wouldn't want to put my life on thier dependability.
 

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Discussion Starter #5
After laying awake half the night trying to figure this out I came to a similiar decision. It has to be the rubber. I plan on pulling them this evening. All my attempts where to the field of the rubber lines.
 

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there is also a valve in line that shuts off fluid to a leaking wheel cylinder. there is instructions on the board for bleeding, something about 2 wheels at a time, one front and one rear to prevent the valve from blocking the breaks.
cliff
 

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Trained (ex)Professional, , 1953-2018 RIP,
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there is also a valve in line that shuts off fluid to a leaking wheel cylinder.
Unfortunately, this is a perpetuating misconception. Please read this thread (and the links) on how the brake pressure differential valve and rear brake pressure reducing regulator work.
 

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and in the second response to the thread shown, it is stated that the breaks need to be bled two wheels at a time, left front, right rear, then right front and left rear. we had the same problem bleeding my sons 69 spider.
My old spider lost a drain plug somehow for the rear, the front still worked till the pads wore out. thats when I found about the rear drain plug.
cliff
 

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Trained (ex)Professional, , 1953-2018 RIP,
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The reason for bleeding one front and one rear brake at the same time is to keep the BPDV pistons centered. This prevents the brake failure warning light on the dash from coming on and, with a non self centering BPDV, eliminates additional labor needed to reset the valve.
 

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Discussion Starter #10
What I have been able to discern, from the thread and from the link, is that my '71 Spider has a single booster and a MS with dual outputs. I do not believe I have a DPDV valve for this reason. If I do it is very well hidden. I pulled the rubber on the fronts and that appears to have been the problem as fluid easily flowed from the metal lines. Ordered new rubber fron Centerline. When I think about it I can't believe this wasn't my first purchase. Many years ago i had a '72 Fiat spider. Almost got killed when a rubber brake line split on me. It appears I am not an quick learner!
 
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