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Master Cylinder Reservoir, replacement?

  • Thread starter Thread starter JustA5.0
  • Start date Start date Mar 11, 2008

JustA5.0

Member
May 12, 2007
148
0
16
Toronto, ON
Mar 11, 2008
#1
  • Mar 11, 2008
  • #1
Greetings

Eventually I will be turning the stang into 5-lug, however the MC is shot and I'm looking to replace it with the '93 Cobra 2-port now.

I was going to order an MC from 50resto, and reuse my reservoir as the ones they sell do not come equipped with the low fluid sensor plug on the supplied reservoir. OK seems fine to me, however...

Reading the brake system section of my Ford Service Manual CD and I come across this: "Whenever the small (secondary) reservoir port is removed from the master cylinder, the reservoir assembly must be replaced and new grommets must be installed." Why does Ford tell their techs to discard this? It seems most of the MCs for sale at parts stores do not come with the reservoir at all, which I presume people are using their original ones.

I'm wondering what others have done to retain their low fluid sensor signal, when converting to the Cobra MC? And is there an actual problem with reusing my original reservoir? If there is a problem, where can I order a reservoir that has the low fluid sensor provision still?
 

JustA5.0

Member
May 12, 2007
148
0
16
Toronto, ON
Mar 12, 2008
#2
  • Mar 12, 2008
  • #2
Bump for some help
 

JustA5.0

Member
May 12, 2007
148
0
16
Toronto, ON
Mar 13, 2008
#3
  • Mar 13, 2008
  • #3
Hmm, let me rephrase...

When you've replaced your MC that did not come with a reservoir, did you reuse the original reservoir? If you got a new reservoir, where did you purchase one that included a connection for the low fluid sensor?

Need to know if I use my old reservoir is it not gonna reseal properly or something???
 

trbkrb

Founding Member
Jun 4, 2001
1,976
4
39
Houston, TX
Mar 13, 2008
#4
  • Mar 13, 2008
  • #4
I went through 2 or 3 rebuilt Fox MCs over the years and always reused the same reservoir until I bought a complete new MC that came with a new reservoir. I never had any problems. They may just want the grommets replaced to make sure they seal properly, and new grommets are provided with all the rebuilt MCs I've seen.

Anyway, does the 93 reservoir you are looking at not have the actual mounting point for the low brake fluid sensor, or does it just not have the actual brake sensor mechanism? I thought it was just a magnetic switch that you could switch from reservoir to reservoir. I thought I switched mine over from the old reservoir when I got the new Fox MC.
 

Fett

New Member
Nov 2, 2004
766
6
0
Mar 13, 2008
#5
  • Mar 13, 2008
  • #5
Yea, the reservoir is reusable. I would replace the two grommets...but most masters come with new ones anyway.

Just be careful when removing your reservoir.
 

JustA5.0

Member
May 12, 2007
148
0
16
Toronto, ON
Mar 13, 2008
#6
  • Mar 13, 2008
  • #6
trbkrb said:
Anyway, does the 93 reservoir you are looking at not have the actual mounting point for the low brake fluid sensor, or does it just not have the actual brake sensor mechanism? I thought it was just a magnetic switch that you could switch from reservoir to reservoir. I thought I switched mine over from the old reservoir when I got the new Fox MC.
Click to expand...

Their website says something like; comes with the reservoir and cap, but doesn't have a provision for the low fluid sensor. And the picture shows the plastic portion for the sensor is blank (i.e. nothing to plug-in/attach to). Unfortunately, my car is stored inaccesible until April, so I can't verify the magnetic portion of your statement.

Fett said:
Yea, the reservoir is reusable. I would replace the two grommets...but most masters come with new ones anyway.

Just be careful when removing your reservoir.
Click to expand...
Good to hear, it seemed a little weird to have to replace a plastic reservoir because it was separated from the MC. I will probably order an MC from RockAuto, since I can reuse my old reservoir if need be, they have one for $65ish.
 

trbkrb

Founding Member
Jun 4, 2001
1,976
4
39
Houston, TX
Mar 13, 2008
#7
  • Mar 13, 2008
  • #7
I just checked mine, and the sensor switch does just come out. It is odd that they say it does not have the provision for it, since the 93 Cobras did have the switch I think.

Here are some pics from mine, it is a 94/95 MC
 

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Shakerhood

20+ Year Stangneter
Oct 28, 2004
3,356
208
114
Ohio
Mar 14, 2008
#8
  • Mar 14, 2008
  • #8
My MC is a 93 Cobra unit and it has the Low Fluid plug in.
 

JustA5.0

Member
May 12, 2007
148
0
16
Toronto, ON
Mar 14, 2008
#9
  • Mar 14, 2008
  • #9
Thanks a lot guys, one less thing to worry about :SNSign:
 
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