The terms 'highbridge' and 'lowbridge' refers to the seating layout arrangement on the top deck, and should not be confused with a double-decker's overall height!
A 'highbridge' double-decker has conventional 2+2 seating upstairs, with a central gangway.
'Lowbridge' versions have a sunken gangway on the offside, with rows of four seats from the nearside. This also meant a lower headroom for passengers in the lower deck offside seats!
There was an exception to this though - some operators specified low overall height bodies on the revolutionary Leyland Atlanteans, which were coming on-stream at this time.
Watch this space ....................
The AEC Renowns were unpopular with us engineering staff due to difficult accessibility of some components.
The engine/gearbox unit was not only mounted at a slight angle, (rather than parallel), in the chassis frame, it was also inclined from the vertical, so that the rear cylinder head encroached slightly into the driver's cab behind a bulkhead. The driveline was therefore along the offside of the chassis frame, via a 4-piece prop-shaft to an underslung 'worm & wheel' rear axle.
This driveline arrangement also meant that if the clutch/gearbox needed attention, then part of the staircase assembly had to be removed to gain access.
If a head gasket needed changing, you hoped that the forward head was the culprit, else it meant taking the cab nearside bulkhead out, to lift-off the rearmost cylinder head.
Thank goodness the Renowns had the AV590 engine, and not the gasket failure-prone AV470!
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Topic: Bus nostalgia (Read 262242 times)