Bare "plug" near brake master cylinder

Technical MGB discussion
Dave Wheatley
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Forename: Dave
Surname: Wheatley
Location: SW Scotland

Bare "plug" near brake master cylinder

Post by Dave Wheatley » Thu Apr 23, 2020 1:11 pm

I've just found a bare "plug" lurking out of sight under the brake master cylinder. 1978 MGB GT. Green wire and green/orange go to it. Searched the wiring diagrams but no luck so far. Looks to have stainless tip and is rust discoloured.
Anybody know what it might be?
WP_20200423_003[1].jpg
Pic upside down! Tip is spring loaded. 2 pin plug and socket incorporated.
1978 MGB GT
1931 Austin 7 RM
1955 Standard 10
1972 Ford Cortina
No modern!

Ian Fozzard
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Surname: Fozzard

Re: Bare "plug" near brake master cylinder

Post by Ian Fozzard » Thu Apr 23, 2020 5:12 pm

No idea really Dave, but could be a sensor for coolant or brake fluid? For level or temperature monitoring?
Someone with a late MGB will probably know!

Ian F
1972 BGT, Blaze, Navy trim, recessed grill
1961 Midget, 948cc, Clipper Blue, Blue trim and weather gear

Dave Wheatley
Posts: 96
Joined: Fri Sep 28, 2018 4:55 pm
Forename: Dave
Surname: Wheatley
Location: SW Scotland

Re: Bare "plug" near brake master cylinder

Post by Dave Wheatley » Thu Apr 23, 2020 5:22 pm

Thanks Ian. It's definitely part of the original wiring, and won't stretch any furthur than the master cylinder.
1978 MGB GT
1931 Austin 7 RM
1955 Standard 10
1972 Ford Cortina
No modern!

Ian Fozzard
Posts: 370
Joined: Fri Mar 27, 2015 8:18 am
Forename: Ian
Surname: Fozzard

Re: Bare "plug" near brake master cylinder

Post by Ian Fozzard » Thu Apr 23, 2020 5:26 pm

Maybe Victor will know😁😁
1972 BGT, Blaze, Navy trim, recessed grill
1961 Midget, 948cc, Clipper Blue, Blue trim and weather gear

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Paul Scott
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Location: Milton Keynes

Re: Bare "plug" near brake master cylinder

Post by Paul Scott » Thu Apr 23, 2020 5:40 pm

Hi Dave,
Brake Failure Switch apparently seems to fit the bill.

Pt No:aau2454

Page 53 Dual Line System item #2

Hope this helps

STAY SAFE

Regards
Paul
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MGB Catalogue 2013.pdf
(4.98 MiB) Downloaded 26 times
1975 MGB Roadster
Webguru for MGB Register

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Paul Scott
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Forename: Paul
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Location: Milton Keynes

Re: Bare "plug" near brake master cylinder

Post by Paul Scott » Thu Apr 23, 2020 5:49 pm

1975 MGB Roadster
Webguru for MGB Register

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Paul Scott
Posts: 113
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Forename: Paul
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Location: Milton Keynes

Re: Bare "plug" near brake master cylinder

Post by Paul Scott » Thu Apr 23, 2020 5:57 pm

On Page 24 in the cluster with the brake light switch/hand brake switch the Brake Failure switch is shown with the leads coloured Green + Green and Orange.

Hope this Helps

STAY SAFE

Regards
Paul
Attachments
mgb.pdf
http://www.advanceautowire.com/mgb.pdf
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1975 MGB Roadster
Webguru for MGB Register

Ian Fozzard
Posts: 370
Joined: Fri Mar 27, 2015 8:18 am
Forename: Ian
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Re: Bare "plug" near brake master cylinder

Post by Ian Fozzard » Thu Apr 23, 2020 6:04 pm

Sounds pretty conclusive Paul!! Would like to see what is fitted in that brake line union on Dave's car😬
1972 BGT, Blaze, Navy trim, recessed grill
1961 Midget, 948cc, Clipper Blue, Blue trim and weather gear

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Paul Scott
Posts: 113
Joined: Mon Jan 08, 2018 8:48 pm
Forename: Paul
Surname: Scott
Location: Milton Keynes

Re: Bare "plug" near brake master cylinder

Post by Paul Scott » Thu Apr 23, 2020 6:11 pm

Either in the union or under the master cylinder. But watching the moss video - I would say it is quite important..

I'm impressed with myself finding the correct answer (hopefully).

I read nearly every post that goes on and I am impressed with the knowledge that gets shared. So hopefully my little bit of input on this will help. Now ask me about an electrical cooker fault - I probably would not need to look anything up!!

STAY SAFE Everyone

Regards
Paul
1975 MGB Roadster
Webguru for MGB Register

Ian Fozzard
Posts: 370
Joined: Fri Mar 27, 2015 8:18 am
Forename: Ian
Surname: Fozzard

Re: Bare "plug" near brake master cylinder

Post by Ian Fozzard » Thu Apr 23, 2020 6:13 pm

Good job Paul😊👍
1972 BGT, Blaze, Navy trim, recessed grill
1961 Midget, 948cc, Clipper Blue, Blue trim and weather gear

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