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PostPosted: Fri Jan 22, 2016 4:38 pm 
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Further to my contention that the 'customer' Self Changing Gears Ltd gearbox and the Leyland Motor Corporation Rationalised Pnuemocyclic were interchangeable to the point of being identical, last night I was told that Dodds of Troon, when cascading Willowbrook bodied AEC Reliances XAG119,120K to local bus duties from limited stop use not only used the bus seats from withdrawn Seddon Pennine RUs but the SCG gearboxes too.

To prove the point Mr Macduff provided a sound recording...


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PostPosted: Sun Mar 31, 2019 9:38 pm 
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Bruce A. MacPhee wrote:
There was, of course, sharing of Leyland engines and Albion gearboxes between these two makes. For some reason, Leyland gave their own designations for Albion boxes used in Leyland chassis: the Albion GB236 in a Tiger Cub was a GB108, yet on chassis build-sheets, the Albion designation GB236 was used!



As I understand it, the Tiger Cub used the GB236 right through until the end of production, never being changed over to the GB241. So even though the GB241 was intended as a group replacement for the GB236, Leyland had to keep the older model in production just for the Tiger Cub.

I imagine that the GB236 was preferred for the Tiger Cub because it readily permitted a robust and more precise remote shift, whereas the GB241 did not. The GB236 was also used on the Albion Aberdonian through to the end of its production run in 1960. That model also had the option of the GB240, the 6-speed overdrive derivative of the GB236. But the GB240 was never offered on the Tiger Cub. Perhaps it was too long to fit without undue shortening of the tailshaft? If so, did the Tiger Cub have a more rearward placement of its engine than the Aberdonian? Or perhaps it was thought that the availability of the 2-speed axle on the Tiger Cub allowed a 5th high overall ratio that was tantamount to being an overdrive?

The Albion Nimbus, from which the Aberdonian was derived, did get the GB241 in its final, NS3A iteration. But I understand that the simple remote control system used resulted in a gearlever with a rather large side-to-side movement.


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PostPosted: Thu Apr 04, 2019 7:04 am 
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Stephen Allcroft wrote:
The only Atkinson buses I know of to have been fitted with the classic Leyland Pneumocyclic pedestal-shift were Sunderland Corporation 46-8 (WBR246-8) although 46 was initially supplied with a David Brown manual gearbox and returned to Atkinson for a semi-auto unit prior to Sunderland licensing it.


North Shore Transport (NST) in Auckland had a single Atkinson Alpha with Gardner 6LHW engine and direct air-operated Wilson gearbox with Leyland pedestal shift. This dated from 1957 and passed to the Auckland Regional Authority when it acquired NST in 1971.

The semi-automatic version of the Alpha, with the pedestal shift, was announced in Commercial Motor (CM) 1953 November 06. Therein is was stated that the gearbox was made by SCG. Presumably it was the RV16 model.

The Atkinson announcement was two weeks ahead of that for the Leyland Pneumocyclic, which was announced in CM 1953 November 20. In that article it was noted that the control system, developed by Leyland, was the same as that used by Atkinson. A later article in CM 1954 March 05 referred to Leyland manufacture (at Leyland) of the Pneumocyclic gearbox, noting that Leyland had strengthened some components, presumably as compared with the SCG original.

Daimler did offer the Leyland gearbox and pedestal control as an option on the Freeline, but as far as I know, nonesuch were built. The pedestal is shown in this page from the pertinent sales brochure (it was undated).

Attachment:
Daimler Freeline Air System p.04.jpg
Daimler Freeline Air System p.04.jpg [ 729.82 KiB | Viewed 389 times ]


But at the time, these were third-party applications rather than internal cross-use.


Cheers,


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PostPosted: Tue Apr 09, 2019 2:32 am 
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A question pertinent for this thread is when did Albion and Leyland start using each other’s major components. The following are the earliest examples that I can find.

The Leyland Comet 90 forward control, ECOS2, was announced in Commercial Motor (CM) 1953 October 02. It was fitted with the Albion GB236 5-speed gearbox, which I think had been designed before Leyland’s takeover of Albion. For Leyland its all straight-tooth nature may have been somewhat regressionary, given that Leyland by then preferred helical gears for the indirects.

The Albion Claymore FT was announced in CM 1953 November 06. It used the same 4-speed gearbox that Leyland had developed for the Comet to replace the original 5-speed all-helical unit. That changeover had been announced in CM 1953 May 08. Perhaps that gearbox had been developed with the FT in mind, although its use therein was something of a stopgap, as it was replaced by the Albion 4-speed synchromesh unit after approximately a year. The FT engine was essentially a four-cylinder version of the Leyland O.350, albeit developed by Albion.

The Albion HD models were swung over to the Leyland O.600 engine, replacing the Albion 9-litre engine, announced in CM 1953 December 04.

I am not sure when Albion’s use of the Leyland O.350 engine commenced. But the Chieftain Six-Wheeler, announced in CM 1954 September 17, appears to have started life with just the Albion four-cylinder engine available. As this would have been a logical application for the O.350, a reasonable assumption is that option arrived somewhat later on.


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PostPosted: Tue Jun 18, 2019 3:58 am 
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9711T wrote:
Daimler did offer the Leyland gearbox and pedestal control as an option on the Freeline, but as far as I know, nonesuch were built.


Not so. Commercial Motor journal, in an item on that year’s Brussels show in its 1956 January 20 issue, reported:

“A new use for the Daimler CD 650 engine is seen on the Miesse stand. Here, in addition to a Daimler Freeline coach chassis with Pneumo-Cyclic gearbox and an Atkinson Alpha chassis, several goods chassis of Miesse manufacture are shown with the Daimler power unit.”

So at least one Pneumocyclic Freeline was built.

As an aside, it was interesting that the Daimler CD650 engine, as “delicate” as it was, found third-party applications, and in trucks.


Cheers,


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