cav551:
oiltreader:
Thanks to VALKYRIE for the detailed info on the decker
Oily
An East Kent OMO in good nick.390 DKK owned by Brian Catchpole is very active on the running day scene. AFAIK this was originally a Coach but like other M&D Reliances converted to dual purpose spec. Built to 2MU3RV spec the bus was originally powered by an AEC AH 470 engine and vacuum braked. After numerous head gasket failures in preservation it was decided that persevering with this particular 470 engine was not a realistic proposition and neither was the work involved in simply fitting another. Brian decided that the best option was to substitute an AH 505. THe actual engine change apparently proved quite straight forward however there was a problem with the braking system since no AEC 505 engines were ever built for vacuum braked vehicles. The exhauster drive gear has teeth of a different pitch and angle to those on a compressor. There is a lengthy article somewhere on t’internet describing the lengths necessary to overcome this problem. When I find it I shall post a link.
Sorry CAV but for the sake of accuracy I must contradict you. BRS had AV505 Mercury tractor units with both a compressor and an exhauster. BRS still had hundreds of vacuum braked trailers in the mid 1960s. My uncle bought Mercury tractor unit HUB 311E second hand in 1970, ex-BRS Leeds and it had both braking systems. It came with a vacuum tank as well as air tanks, air brake susies, and vacuum susies. In fact we never took them off. All that lot behind the cab looked quite impressive.