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Brake Fluid Levels

Hi gents, got a question for you all;
Recently topped up the brakes with the correct hydraulic oil,as it was a bit low, now the flag drops randomly and the brake warning light comes on intermittently, when I apply the brakes, the flag goes up and the light goes out.
Brakes are working fine, and still can pump the brake pedal 12 to 14 times before the flag drops with the engine turned off. is it possible I hve iverfilled the hydraulic reservoir?

My bus number (if any): RML 2353, MB 306, MS 1103

Re: Brake Fluid Levels

Just about possible with the right combination of factors. If seriously overfilled I suppose that when the hydraulic pressure decayed to nil in the accumulators, the level in the tank rose sufficiently for fluid to spray out of the tank breather onto the electrical terminals for the microswitches themselves or the terminal block nearby.

Otherwise it is a genuine indication and a coincidence that a common fault has triggered, so this must be assumed to be correct unless there is clearly evidence of the above. So what is the air pressure in each accumulator when the brakes have been pumped until ALL Hydraulic pressure has gone and none of the brake operating levers move? What is the level of oil in the tank according to the sight glass at that point?