Removing Brake Lines from Master Cylinder

Maintenance advice to keep your Spider in shape.
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drovak

Removing Brake Lines from Master Cylinder

Post by drovak »

Hey guys,

For the LIFE of me, I cannot remove the brake lines from the master cylinder. The cylinder itself is a bit rusty, and even after two days of letting penetrating oil soak in, the nuts do not budge. The last thing I want to do is strip the nuts. I've tried vice grips and a 10mm knurled nut wrench, both of which have been unsuccessful.

What are my options? Thanks!

Kyle

P.S. I am removing the booster and cylinder so I can assess the firewall damage. It looks quite bad from the inside, unfortunately...that clutch cable didn't treat the firewall very well apparently.
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azruss
Posts: 3659
Joined: Sun May 30, 2010 12:24 pm
Your car is a: 80 Fiat 2000 FI

Re: Removing Brake Lines from Master Cylinder

Post by azruss »

you can try a 10mm brake bleeder wrench and hold it closed with vice grips. a little heat might help.
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manoa matt
Posts: 3442
Joined: Thu Oct 26, 2006 4:28 pm
Your car is a: 1978 Fiat 124 Spider 1800
Location: Honolulu, Hawaii

Re: Removing Brake Lines from Master Cylinder

Post by manoa matt »

Kyle, You can remove the master cylinder from the booster without disconnecting the hard lines. Remove the 4 nuts on the booster mounting plate up in the foot well on the inside. Remove the two nuts on the booster to master cylinder mounting. Carefully move it out of the way, without kinking the hard lines. You don't have to bleed the entire system either.

If that does not work you need a 10mm "flare nut wrench"
drovak

Re: Removing Brake Lines from Master Cylinder

Post by drovak »

Besides the two bolts connecting the master cylinder to the booster, how is the booster diaphragm connected to the master piston? Is there some linkage I will need to disconnect?

Thanks again for the help. I was quite close to draining the brakes. Glad I shouldn't have to!

Also, I think I used the wrong terminology. I meant flare nut wrench, not knurled nut. I did get a 10mm, but I can see it slip. If I kept trying, I'm sure I'd strip it.

Kyle
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124JOE
Posts: 3141
Joined: Fri Jun 24, 2011 7:11 pm
Your car is a: 1978 124 fiat spider sport 1800
Location: SO. WI

Re: Removing Brake Lines from Master Cylinder

Post by 124JOE »

i use a small vicegrip on every brake line,smash it real good but not too much.
tightenuff for a good wack with a hammer if needed.

after a good soak in penat... oil ofcorse.joe
when you do everything correct people arent sure youve done anything at all (futurama)
ul1joe@yahoo.com 124joe@gmail.com
spider2081
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Patron 2024
Posts: 3015
Joined: Fri Jan 27, 2006 11:45 pm
Your car is a: 1981 Spider 2000
Location: Wallingford,CT

Re: Removing Brake Lines from Master Cylinder

Post by spider2081 »

In case you choose to take master cylinder off.

I learned the hard way. A flare nut wrench is the proper tool for disassembling brake lines and other hard line fittings. Also I learned not to purchase the least expensive set of these wrenches as they will spread open and damage the nut. I purchased a Craftmans set and they work if I squeeze them tightly with a pair of vice grips. I have used an SK brand and it did not require the use of vise grips.
I like to heat brake line fittings with a propane torch before attempting to loosen. Keep in mind that brake fluid is highly flamable so system should be drained if you choose to do this. Heat and PB blaster seems to be a good combination in freeing frozen parts.

I keep a couple of fire extinguishers in the garage.
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