Are you sure it's the correct one? As Charles said, all dual circuit brake master cylinders have the fitting for the pressure warning switch. The part number in my parts list book is GMC 149 and it includes the reservoir which is held on the top of the cylinder by 2 screws. Have you compared it to t...

Only if the car is manufactured in an earlier year to which it was registered like mine is to claim Historic status.To be MOT exempt the vehicle must be in the Historic taxation class and thus MOT exemption can be self declared unless the vehicle has been "substantially modified." Not necessary in y...

Not Anumber. Bleed the brakes exactly how the workshop manual says otherwise there's a chance the piston will be decentralized. They must be bled in the correct order and with the correct pedal action.

That's a clear photo Charles. My MGB GT was Ziebarted from new so the engine bay is black and the relays and wiring don't stand out like yours.

The relays are "start" and "run." As the name explains, one cuts in when the starter motor is running to supply a direct 12v supply from starter motor to coil, and when the engine has started and the key released from the start position, that relay cuts out and the run relay is activated to supply t...

I removed the broken switch using a mirror, torch and tapped the remains with a thin screwdriver. It came undone easily. As Charles said the switch is available. I suspect if the car was MOT'd it might fail as the light wouldn't be working when the handbrake was applied unless that didn't apply due ...

Dave, that's what happened to my switch when I started to loosen it prior to brake bleeding. I did extract the remains. If you have to bleed the brakes, use a pressure or vacuum bleeding system. So long the brake pedal isn't moved during the process the differential piston shouldn't move. However, y...

Charles, I had a look at the connector to the pressure switch and I see what you mean about the connector. I suppose some sort of connector could be made but I agree it would be simpler to connect the electrics first then apply the brakes and see what the warning light does.

You could try and see if there's a circuit between the 2 contacts on the switch using a multimeter set to circuit continuity. Make sure the switch is screwed fully in first. If there is a circuit then it's essential you bleed the brakes per the manual, starting by slackening the pressure warning swi...

Thanks for the info Charles.