London General – Dennis 4 ton – XX 9591 – D 142

London General - Dennis 4 ton - XX 9591 - D 142

London General Omnibus Company
1925
Dennis 4 ton
Dodson O26/22RO

Pictured at South Croydon on the May 1972 HCVC London – Brighton rally is Dennis 4 ton XX 9591, D142 of 1925 with the  almost inevitable Dodson O26/22RO bodywork. This bus has a complicated history that is detailed on the London Bus Museum website

Although a service was run by Charles Waymann in the Waltham Abbey area from 1920 to 1926, initially using a single decker and a double decker, both of the B type, and a Straker Squire double decker, the first “Pirate” bus in central London is generally credited as being the Leyland operated by Arthur George Partridge, which took to the road on 5 August 1922 under the trading name “Chocolate Express” (though only "Express" appeared on the body sides). The vehicle was a Leyland LB1 (i.e London Bus), a straight chassis vehicle developed from the heavier standard G7 model specifically to meet the stringent Metropolitan Police design requirements. There followed a flurry of activity in 1922 as other opportunist entrepreneurs entered the fray using a great variety of vehicle makes, but the Independents’ choice of double decker manufacture soon generally settled down to that between the Leyland LB (developed as the LB2, then LB4 and finally LB5) and the equally sturdy Dennis 4 tonner. The Dennis was a straight framed haulage chassis derived from the wartime “Subvention” or “Subsidy” type, of which over 7000 were produced in various wheelbases and weights between 1914 and 1918. A few single deck Dennis buses appeared on the London scene in 1922, but, to gain proper access to the lucrative London market, Dennis sought the acceptance of the 4 tonner by the Metropolitan Police as a passenger carrying double decker. Accordingly, the bus variant of the 4 ton model was modified for London in 1923 and emerged with the following specifications:-
Wheelbase extended from 15ft 6ins to 15ft 10ins
Larger front wheels from 720mm to 850mm
Cone clutch, four speed sliding mesh gearbox, overhead worm rear axle (contemporary LGOC buses had 3 speed chain gearboxes – it would seem that, even way back then, AEC spur gearboxes were noisy and unacceptable to the Met).
Body O26/22RO
CAV lighting set
The first 4 tonner for London operation was reported in Commercial Motor in August 1923 as being destined for Messrs W.H. Collins and Co. trading as A1 and painted chocolate brown. The engine, described below, was supplied by the White and Poppe factory in Coventry, set up in 1899 by Alfred White and Peter Poppe (pronounced ‘Popper’ – he was a Norwegian). This company became the main supplier of engines to Dennis who went on to purchase the Coventry firm in the post war recession of 1919.
‘T’ head side valve, 4 cylinder
115mm x 150mm = 6.232 litre, 40 -50 bhp
This engine, stated in the 1923 report as being the power plant of the 4 ton bus, was a widely used and successful unit, 4591 examples being made up to the Dennis takeover in 1919, and it then continued in volume production until the late 1920s. This was certainly the standard engine of the 4 ton double decker. A modified version uprated to 70 bhp was fitted to Dennis’s first bespoke bus chassis, the E type of 1925.

Now comes the conundrum. The power unit of D142 is stated on sundry preservation pages to be an example of the Type D, with a capacity of 5.8 litres yielding 36 bhp. However, the Type D engine (derived from its precursor, the Type C manufactured from 1913) is listed in Dennis drawings as:-
‘L’ head side valve, 4 cylinder
110mm x 150 mm = 5.702 litre, 44 bhp
Thus the alleged engine type of D142 is not consistent with the claimed capacity. The nearest White and Poppe engine of 5.8 litres was this 4 cylinder side valve, very unusual in a time of long stroke engines in being almost "square", and thus probably intended for private car applications:-
120mm x 130mm = 5.881 litre, 40-50 bhp, but only 209 of this engine version were made before the Dennis takeover in 1919, and it does not appear in the Dennis list of engine drawings from that date, which indicates that it was not produced later. Unless the preserved vehicle has improbably received a very rare earlier type of White and Poppe engine, which is emphatically not the alleged Type D anyway, the 5.8 litre engine description must be considered doubtful. I believe the engine in D142 to be the standard 6.232 litre unit approved by the Metropolitan Police, but comments would be welcome.

Photograph and Copy contributed by Roger Cox

 

Ribble – Leyland Atlantean – RRN 414 – 1814

RRN 414

Ribble Motor Services
1962
Leyland Atlantean PDR1/1
Weymann L39/33F

Seen in August 1969 in less than pristine condition leaving Manchester’s Lower Mosley Street Bus Station (often confusing us slow witted southerners by appearing on bus destination blinds as “Manchester LMS”) is Ribble 1814, the last of a batch of fourteen Weymann bodied lowbridge Atlanteans on the original PDR1/1 chassis. This was fitted with a straight rear axle which required the lower deck to incorporate a step to gain access to the uplifted rear part of the saloon. The corresponding rear section of the upper saloon also had to be raised, so that a side gangway of the traditional lowbridge variety was employed in that area, though this was located on the nearside of the vehicle (front engined lowbridge double deckers had the gangway on the offside to avoid fouling the passenger entrance). The 1801 -1814 lowbridge Atlanteans were the last examples of the PDR1/1 chassis to be bought by Ribble.
Another OBP page showing one of these Atlanteans may be found here:- At this link
and a comprehensive article by Neville Mercer on Lower Mosley Street is here:- Lower Mosley Street – Article

Photograph and Copy contributed by Roger Cox


13/03/18 – 06:06

I think by 1962, the bodywork on these lowbridge Atlanteans had improved somewhat on the original examples which came out in 1959. The single skinned fibreglass domes (which tended to crack) had been replaced by double skinned ones, the interior face being a sort of brilliant white plastic which seemed to resist yellowing very well. Other small improvements to the interior trim and panelling made the general ambience feel noticeably better and I quite liked to travel on the later ones. I believe both Ribble and PMT got very long service lives out of them in spite of the problems they were supposed to have had.

Chris Barker


17/03/18 – 07:15

Looks like someone tried to prize off the Ribble fleet nameplate on the front panel.
Perhaps her less than pristine condition is down to her being due her seven year Check/Overhaul.

Cyril Aston


18/03/18 – 06:47

Ribble got very good service from these some lasting into the eighties

Chris Hough


18/03/18 – 06:47

Quite a sad photo, I can’t remember which particular bus it was, but had a trip on one of this batch when brand new on the X23 from LMS. I suppose I haven’t worn any better than the bus! Personally I enjoyed riding on the lowbridge Atlanteans. PMT used them on the Stoke-Stafford service which like the Ribble services gave them a good chance to open up. Travelling in the rear upstairs was quite smooth, I suppose the lower height lowered the centre of gravity, resulting in a better ride.

Andrew Gosling


07/05/18 – 07:13

PMT certainly got their moneys worth out of their 105 lowbridge Atlanteans. A lot depended on the Depot. Frank Ling who was Resident Engineer at Longton Depot achieved phenomenal engine mileages out his Atlantean fleet by carefully and diligently looking after them. recollection is that he had 4 spare vehicles for a PVR of 58 so not a lot of spare capacity there. Mind you, Frank also managed to run quite successfully a sizeable fleet of Albion Aberdonian single deckers which again other Depots failed to do so. Memory fades but I’m sure that some batches of PMT’s Atlanteans also had a plastic finish to the inside of the front domes.

Ian Wild


19/07/18 – 07:13

Stafford garage had a duty on the 10 service which I occasionally worked for my rest day. The Atlantean would probably be 909 and occasional 910 these buses belonged to Hanley garage and were serviced by them. They were a pleasure to drive and were both quite fast. Happy days !!

Michael Crofts


27/11/19 – 08:47

With regards to PMT Stafford garage I would add that both 909 and 910 were the resident Atlanteans and they were serviced by Stoke garage, not Hanley. They were indeed fine buses.

Leekensian


26/01/21 – 06:12

I remember the first time I travelled on one of these as a ten year old and not being able to see out of the front windows because the sill-level was so high.
What were the designers thinking of?

Philip Smithies


27/01/21 – 06:13

Philip S – A simple answer to your question – saving money. Shallow windows cost less than deeper ones. Even in those days 60 or more years ago, financial considerations were very important, especially to a commercial organisation like the BET Group.

Nigel Frampton


10/11/21 – 06:36

I joined British Airways Motor Transport Dept in June 1976′ Part of my very varied duties included operating the PDR1/1 Leyland Atlanteans to and from the British Airways Terminal 3 operation to The Victoria BA Terminus. ps, (no power steering on these Atlanteans). Several of us also operated the Leyland Mastiff airside tractor units pulling the 100 odd passenger articulated trailers. Maximum concentration of course winding the latter around the confines of airside roads and aircraft stands. In contrast we also transported flight deck and cabin crew in various coaches and Ford Granada cars etc. A super job that we just took for granted at the time.

James

 

Brighton, Hove & District – Bristol Lodekka – OPN 807 – 7

Brighton, Hove & District - Bristol Lodekka - OPN 807 - 7

Brighton, Hove & District
1959
Bristol LDS6B
ECW H33/37R

Seen in Brighton in the summer of 1960 is Brighton, Hove & District OPN 807, fleet no. 7, an example of the rare LDS short version of the Bristol Lodekka with flat lower saloon floor, air suspension on the rear axle, and air (instead of vacuum) over hydraulic braking system. With some adjustments, the LDS model then went into volume production as the FS type. The prototype LDS, an LDS6G with Gardner 6LW engine, went to Crosville in 1958 as 285 HFM, fleet no. DLG 949. In May / June 1959, BH&D received LDS buses OPN 801 to 808, the company’s first Lodekkas, which were powered by the then newly introduced 8.9 litre Bristol BVW engine. OPN 804 to 808 had ECW H33/37R bodywork, but OPN 801 to 803 were CO33/37R convertible open toppers. www.flickr.com/
As delivered, these eight LDS6B buses had the Cave-Brown-Cave heating system installed and, as seen in the photograph, lacked a conventional radiator at the front of the engine bay. The deficiencies of this heating/cooling arrangement, especially apparent with the overheating prone BVW engine, led to its subsequent disconnection and the fitment of a normal radiator, though the cooler running Gardner powered Crosville prototype retained its Cave-Brown-Cave heating and blank front panel with winged motif to the end. OPN 807 served with BH&D until January 1969 when, under NBC “rationalisation”, it passed to Southdown ownership with all the BH&D operations. Withdrawn in 1972, it then went on to Brittain’s in Northampton //bcv.robsly.com/ who sold it, ostensibly for preservation, in June 1979. Having since passed through a number of supposedly preservationist hands, it would seem that it still exists in the current ownership of a dealer, the London Bus Export Company of Lydney, though its current condition is uncertain. If it still retains its BVW engine then spares for that will be scarcer than hen’s teeth.

Photograph and Copy contributed by Roger Cox


18/02/18 – 17:05

APN 54B

Prodded by Roger’s item, I Googled LDX 003 and found Nigel Furness’ book mentioning LDX003 and LDX004 both of which had passed me by! His book also adds that BCV changed the designation of the six LDL 30′ chassis built in 1957 (eg Bristol L8450 – see //www.old-bus-photos.co.uk/?p=34464 to LLD after they were built which explains why I had come across this confusing reference at some time whilst at BCV.
Roger’s photo reminded me of one that I took at BCV in early 1964 showing no. 4 with two non-standard to Tilling Group features of these vehicles: the split step (making a ‘stepless’ entry into a stepped access!); and the side route no. indicator. The first feature is still extant in the photo-link of no. 7 in Brittain’s ownership.
When I took the photo I had just arrived back at the factory at Brislington after a long spell with BOC so was not aware why no. 4 was at BCV. It was the first of the eight LDS chassis built at the end of the 138th sanction for BH&D, although the last three with convertible open top bodies were given fleet nos. 1 -3. I also have a note to say that its BVW engine was fitted with a DPA (distributor) type fuel injection pump, instead of the original in-line fuel injection pumps of either CAV or Simms manufacture. I’m not aware that this cheaper component was adopted as a standard in later BVW engines.

Geoff Pullin


19/02/18 – 07:07

Whoops – got confused. This photo is of BH&D no. 54, not 4 and hence is an FS6B of the 214th sanction dating from 1964. The bit about DPA pumps definitely refers to 5no. 4!

Geoff Pullin


19/02/18 – 07:08

Thanks for the picture of the "stepless" door platform on these buses, Geoff. I had completely forgotten about these, but I now recall that they were held to create more platform stumbles than they sought to eradicate. Your reference to the use of DPA fuel pumps on these early BVW engines is notewothy. DPA pumps appeared in the mid to late fifties on smaller engines, but this must surely have been one of the pioneer applications on a relatively large commercial vehicle engine. Was it intended to thus equip the production BVW as standard? I am not an engineer, just an interested layman, but I can recognise the appeal of the DPA against the traditional, much more costly, in line pump. The DPA has to work harder serving all the injectors, but the advantages of cheaper and easier replacement together with simplified calibration must have been attractive. Was reliability a problem, and did these early Lodekkas keep these pumps?

Roger Cox


19/02/18 – 07:08

I remember these Lodekkas from my gap year conducting from Conway Street in 1969/70. The lowered rear platform step was said to be popular with all the old ladies of Hove but in rush hour with visitors and foreign students they were also what we now consider a trip hazard. Happy days!

Anthony H


20/02/18 – 06:03

As of Feb 12 it was still at Lydney. Gossip says it was possessed over an unpaid bill. I would have thought offering it for continued preservation would have attracted a buyer.

Roger Burdett


21/02/18 – 07:26

steps

Reading Geoff Pullin’s post regarding Brighton & Hove APN 54B and its modified entrance step, it put me in mind of a similar design modification applied to a East Midland VR some 9 years later. PRR 121L and its low entrance step option was presented to the local press in Mansfield as a help to the aged and infirm. I don’t know how long it lasted but photos on the web show it had gone by the time Yelloway became the owners. I captured my picture when nearly new at Mansfield depot.

Berisford Jones


28/02/18 – 07:37

Berisford’s photograph of East Midland VRT PRR 121L’s step arrangement has reminded me that one of East Yorkshire’s 1973 VRTs (932) was similarly treated, but was converted to standard layout in later life. Maybe such experimental steps were more widespread than maybe first thought.

Brendan Smith


28/02/18 – 12:21

I seem to remember that ECW did about half a dozen VRTs with this step as an experiment in 1972/3 – another one was Trent 631 (RCH 631L), which was converted to normal within a year or so.

Bob Gell


03/03/18 – 06:40

Roger asks about the DPA fuel injection pump. To my knowledge it was never used on production BVW engines, but others may know differently! I can’t find any information about its introduction to other makes of engines but remember that it was used by Leyland on 680 engines in AN68 Atlanteans and later Leopards and probably Panthers. I can’t remember about the 500/510 series.
The DPA did have some reliability problems but the reduced initial cost and ease of replacement was probably thought to compensate in Leyland’s eyes. It was not suitable for increasing power outputs at a time that competition was pushing them up. The ‘Power Plus’ series of 680 engines used in trucks were fitted with in-line fuel injection pumps and that was the engine used in the Ribble / Standerwick VRL/LH coaches and why they were able to go ‘uphill at 70mph’ compared to 36ft Leopards, which were stuck with the DPA version because the in-line pump would foul the chassis frame. We had to wait for the Tiger before this power problem was sorted!

Geoff Pullin


04/03/18 – 06:50

From memory the later 680’s had an F&M Friedmann and Maier injection pump fitted.

Andrew Charles


05/03/18 – 08:02

Geoff, thank you for the fascinating information regarding BH&D 4 being fitted with a CAV DPA distributor type (sometimes known as rotary) fuel injection pump when new, as I had no idea of such an experiment. As you comment, the standard BVW engine was fitted with an in-line injection pump of either Simms (SPE type) or CAV (N type) manufacture, although I seem to recall that in later years the CAV pump became the norm. West Yorkshire’s 0.680-engined Bristol RELHs and Leyland Leopards were fitted with DPA pumps as standard, apart from a handful of WY’s last Leopards which had Austrian-built Friedmann & Maier (F&M) in-line pumps. F&M injection pumps were also used on Leyland-engined Leyland Tiger TR and National 2 models. The Leyland 510 engine fitted to the National 1 used the CAV NN-type pump, which was a development of the N-type, the immediate difference being that the NN had its oil supplied from the engine lubrication system, whereas the N was simply ‘splash fed’ by oil from its own small ‘sump’. Also, on the National engine the injection pump was laid on its side rather than being vertical.
As Roger says, the cheaper initial cost, ease of removal/replacement and simplified calibration were in the DPA pump’s favour, but I would tend to agree that the pumps would have had to work harder than a larger in-line pump on more powerful engines. The main problem WY had with DPA pumps related to fuel leaks, mainly although not solely, around the banjo bolts retaining the high pressure outlets to the injector pipes. I think Geoff is correct in thinking that the DPA pump was not suited to the steady increase in power outputs on large diesel engines in later years, although CAV did introduce the DPC (Distributor Pump, ‘C’ type) to help counter this, but I’m not sure as to its success. Going back to the DPA pumps, it came as something of a surprise when I first saw one on a 0.680 Atlantean engine. The pump looked so small on the side of such a large engine, especially when compared to the very large (but admittedly long-lived) injection pumps used by Messrs L Gardner & Sons on their range of engines!

Brendan Smith

 

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