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MG MGB Technical - Connector for the AAU2454 D/circuit b/warning l/sw

Hi,
Following on from removing the heater box (see my previous post) I have disconnected the main wiring harness from the body & gearbox harnesses. In the process I removed the connector plug from the switch beneath the brake master cylinder.The pins of the switch were badly corroded and one came away embedded in the connector.Does anyone know where I can source a new connector which I can then a fix to the wires of the harness as I can only find the switch itself which also needs replacing. As a separate point I believe I can simply unscrew the old switch without draining off any brake fluid assuming the seals inside the master cylinder are not leaking round the balancing valve that the switch stem tracks?
Cheers
Charles
Charles9

I believe you are correct regarding the switch. For the harness connector I doubt you will get one other than off an old harness, so try people like Andy Jennings and Welsh MG and see if they are willing to cut one off. Failing that come back as I may have one.
paulh4

Charles, looking through the archives it looks like that connector you are after is rarer than hens teeth. If you cant find a suitable replacement, then a workable solution may be to blank off the pressure switch entirely with suitable bolt and washer and fit a new filler cap to your master cylinder with a low fluid switch incorporated. This may be not such a bad idea as I have read that these pressure switches have a tendency to leak. See these links as an examples:

https://www.ebay.co.uk/itm/CLASSIC-MINI-BRAKE-MASTER-CYLINDER-CAP-FLOAT-SWITCH-GRK6009-AEU1796-3E3-/381589030434

http://www.leacyclassics.com/aeu1796.html

This would enable you to use your existing wiring to your warning light by using spade terminals and will give you an indication of low brake fluid. I have fitted one of these to my own roadster as an additional safety feature (single circuit brakes with plastic master cylinder reservoir) and fitted a warning light. It works a treat.

Andy
Andy Robinson

Note that the float switch is a different function - low fluid level as said rather than circuit imbalance as for the original switch. If there is a leak, then yes one of the circuits would lose fluid, i.e. the level will drop, and more for the faulty half then the good half. The float is probably in the rear half, which is the front circuit, and you would soon know if you had lost that as it would leave you with almost no braking. You probably wouldn't if it was the rear circuit which is the front section of the master, so the question is, does the level in the rear half drop far enough if the front half empties?

I agree a fluid level warning is very useful for single-circuit systems, especially with the remote master which can drain the master under certain fault conditions. I've added it to both mine, which have the original metal masters.
paulh4

Thanks Paul & Andy,
I am pursuing Paul 's earlier suggestions first , but may go down Andy's if I have no success.I wonder what the makers of new harnesses do????!!!!
Cheers, Charles
Charles9

I assume they have access to the connectors. If you have access to the manufacturer you may be able to snaffle one, but many components that are part of retail assemblies are just not available retail themselves. Many years ago our son inherited a tricycle with worn tyres. The manufacturer was in Birmingham so I went round on the off chance and they gave me three new chrome wheels. This was in the days before 'chuck it and buy new', or 'made in China, mate'.
paulh4

Hi Phil,
I contacted your two suggested sources for the connector & Phil at Welsh MG has come up trumps! I have however a fair bit of work to do under the bonnet before I will get to fit it,but at least it is one problem off my list.
Many thanks.
Charles
Charles9

Apologies I should have said Paul!!!
Cheers, Charles
Charles9

No worries, I've been called many things :o)
paulh4

This thread was discussed between 10/12/2017 and 13/12/2017

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