Hi All,

Trying to replace hydraulic pump, but don't have any specification to replace with.
does anyone know what pressure the hydraulic steering and brakes run at?

Regards,

My bus number (if any): RM1005

Yes probably, but more information required. Not all buses are the same. There have been seven different makes of engine fitted; three different models of which from one manufacturer alone.

It is repowered with a Cummins B 5.9 Euro 1.

My bus number (if any): RM1005

See the Routemaster pressure test thread further down the page for figures. The location of the test points is mentioned. However these figures refer to vehicles with a separate hydraulic pump for each system. The brake system relief valve is attached to the lower accumulator and the PAS relief valve is integral with the engine driven pump. IIRC Cummins 6 BTA powered vehicles have an engine driven tandem pump which was the source of many problems. This pump has an integral relief valve, however there should be an additional inline relief/safety valve fitted to dump excess pressure for when the service brakes are held applied with the vehicle stationary. This is set at 1900 psi. The PAS system pressures will be higher than quoted because of the engine's greater idling speed.However on full lock and maximum revs 1000psi is much too high.

There should be a tag on the hydraulic pump to identify its part number.