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MG MGB Technical - Slow brake lights

I have to put quite a lot of pressure on the footbrake pedal to get the brake lights to come on, this might be normal I don’t know. I have cleaned the electric connections and no difference. Wondered if the switch has become faulty
. A friend following me said the rake lights didn’t come on even when pulling up to traffic lights, I have checked they do come on but only when the peddle is pressed firmly. Thanks
Trevor Harvey

CB or RB i.e. hydraulic switch or mechanical? I'll assume CB. This happens with the original hydraulic switches after several decades of use, and unfortunately it happens within months on replacements from the usual suspects as they are now built so cheaply. I had to replace mine twice in quick succession and the second time added a relay to take the load of incandescent bulbs off the switch, when the switch initially closes i.e. cold bulbs they are trying to take 48 amps. Since then I've converted to a mechanical switch (similar to RB) so they come on as soon as I start moving the pedal i.e. before any retardation.

More info on both here http://www.mgb-stuff.org.uk/lights.htm#switchfail

paulh4

Hi Paul, I assume it's hydraulic as it's part of the 4 way brake line cross piece and has 2wires connected to it..
Is a replacement just the larger piece with the wire connectors on and if that is removed does it mean the fluid is lost .thanks
Trevor Harvey

Yes that switch just screws into the manifold. Slacken it holding the manifold with another implement to stop it twisting and bending the pipes, then unscrew it with your secondary hand and have the new one in your primary hand ready to swap over.

I didn't lose any fluid but I might have put cling-film over the master neck. Wrap some absorbent paper/cloth round the manifold just in case.
paulh4

Paul, I have ordered a Lucas replacement and would be interested in the relay that you mentioned, are these readily available and who from. Thanks again. Trev
Trevor Harvey

Hi Trevor - made to order, more info on ordering and payment here http://www.mgb-stuff.org.uk/lights2.htm#buy
paulh4

I have changed these switches without losing fluid too. Just because you have ordered a "Lucas" replacement, there's a good chance it is made in some far flung place with minimum quality to keep it cheap. Go for a relay as Paul recommends. Takes the load off the switch.
Mike Howlett

Paul, would like one of your brake light relays, not familiar with how to send payment for it. I have a PayPal account and on clicking the donate to PayPal button on your page an unfamiliar page opens, is this correct. Trevor
Trevor Harvey

Clicking on that button I get:

Donate to
I.T. Answers
Donate to MGB-Stuff

Below that is:

Enter amount
£0
GBP

If you click on the £0 it should allow you to enter an amount, then click Donate below that to pay with Paypal, or the button below that to pay with a credit or debit card.

If you get that far make sure your address is included somewhere, Paypal seems to have changed and with the last one I had to get the address through Paypal messaging, or you can email me using the address with this post.
paulh4

If you don't get any of that log into your Paypal as normal, click Send, and use the same email address.
paulh4

Hi Trevor - received, you should get email confirmation from me as well.
paulh4

This thread was discussed between 03/08/2023 and 06/08/2023

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