Class 08 shunters bhp rating

[saddlestoneman]

Hello All

I can see from various sources that the BR Class 08 shunters are rated at 400bhp or 350bhp (which seems to be the commonest). The Ian Allan books are consistent at 350bhp, no matter what engine (EE, Blackstone, etc) was fitted. Hugh Llewelyn's book 'Diesel Shunters' is one example in the 400hp camp.

Are the ones that quote 400bhp simply wrong, or an I missing something?

best regards ... Stef

 

[12LDA28C]

Hello All

I can see from various sources that the BR Class 08 shunters are rated at 400bhp or 350bhp (which seems to be the commonest). The Ian Allan books are consistent at 350bhp, no matter what engine (EE, Blackstone, etc) was fitted. Hugh Llewelyn's book 'Diesel Shunters' is one example in the 400hp camp.

Are the ones that quote 400bhp simply wrong, or an I missing something?

best regards ... Stef

I'm far from an expert on shunting locomotives but I always understood 08s to be 350hp locos. Indeed, one of the various nicknames they had/have amongst traincrew is '350s' due to the power they produce, along with 'Jockos' and various other names.

 

[chuff chuff]

Yeah we called them 350's.

 

[Big Jumby 74]

I would concur that they were known in the industry (by many) as '350's, but on investigation I am about to throw a spanner in the works. One has to be wary of mistakes in printed works being repeated so many times down the years that they can become 'fact', but none the less I will say this;

One of Colin Marsdens 'Diesel shunter' pictorial books has the various types shown in line drawing format with all measurements and statistics. These line drawings I have had a copy of for many years from an internal source way back, and there are several such (seemingly identical) versions for the type we now know as an 08/09 (not the earlier 11/12's with the shallower cab roof profile). All are labelled as 350 HP, but in the finer detail two variants, with references 'DE/360/1' and 'DE/360/2' are shown as 400 HP (at 680 rpm). The rpm figure being standard throughout the type seemingly.

How these 'DE' references tally with particular loco running numbers, I have not worked out - sure it must be listed somewhere.

Further to this, the publication 'British Rail Fleet Survey No 7 - Diesel shunters' (Brian Haresnape) , page 66, Headed '24 BR/EE 350 0-6-0' (etc) states that the present day (published 1984) power rating is 400 hp, and I quote; "The TOPS class 08, nowadays rated at 400hp, forms the main fleet....".

Get the impression from the very early days the 0-6-0 shunter concept was planned around the 350 hp power unit, including the Crossley and Blackstone variants, but as non standard they went in the skip early on, and the remaining EE powered locos were rated at 400hp.

I've learnt something new here.

 

[saddlestoneman]

One of the most comprehensive on-line list of the Class 08s (and 09s, etc) with their built locations, dates of introduction, first sheds, etc rates the 08s at 400hp.

See: http://www.railway-centre.com/uploads/7/2/2/3/7223531/class_08-13_fleet_list.pdf

Interestingly the class 13 master and slave units are only rated at 700hp, ie 2x350hp.

 

[12LDA28C]

One of the most comprehensive on-line list of the Class 08s (and 09s, etc) with their built locations, dates of introduction, first sheds, etc rates the 08s at 400hp.

See: http://www.railway-centre.com/uploads/7/2/2/3/7223531/class_08-13_fleet_list.pdf

Interestingly the class 13 master and slave units are only rated at 700hp, ie 2x350hp.

Not quite - the article specifically states:

At the design stage it was agreed to install the established English Electric six-cylinder 6K power unit for this fleet, set to deliver 350-400hp

Surely it wouldn't be a random value between 350hp and 400hp? An 'established' engine design would have an established and fixed power rating.

 

[Big Jumby 74]

Surely it wouldn't be a random value between 350hp and 400hp? An 'established' engine design would have an established and fixed power rating.

It may just be that at the design stage for the class 13's, as we knew them, the idea of bolting two 08's permanently together in a synchronised power sense was an unknown in the engineering sense, and until the first pair had been done and tested the actual power output figures (at rail level v engine output) may have been a bit of a 'what-if' in the 350-400 range? Interesting point though I agree.

 

[Dunfanaghy Rd]

Wasn't the engine originally intended for use in trawlers, or is that another urban myth?
The ability to change the oil strainers with the engine running suggests a marine origin to me. Maybe there was a different rating in that case?
Pat

 

[Merle Haggard]

Back about 1968 at uni. I used to see a trade magazine for loco. engineers (can't remember the name) in the library and one issue had a long and detailed article about B.R. D.E. shunters. It did identify different powers ratings for different batches - as well as 400 I think 360 also figured. I did photocopy the article and must still have it somewhere. There were lots of other differences - weren't there 2 different control voltages which seemed to be a factor in withdrawal (the B.R. alterations sheets used to show reason for withdrawal) ???

 

[43096]

The BR diagram books available on the Barrowmore MRG website (http://www.barrowmoremrg.co.uk/Prototype.html) shown them as 400hp.

 

[Signal Head]

Back about 1968 at uni. I used to see a trade magazine for loco. engineers (can't remember the name) in the library and one issue had a long and detailed article about B.R. D.E. shunters. It did identify different powers ratings for different batches - as well as 400 I think 360 also figured. I did photocopy the article and must still have it somewhere. There were lots of other differences - weren't there 2 different control voltages which seemed to be a factor in withdrawal (the B.R. alterations sheets used to show reason for withdrawal) ???

From memory, 90v & 110v. I'm not sure if this corresponded with a different battery type, but 75 NiFe cells at 1.2v each gives 90v. Did the 110v examples have Lead Acid batteries?

 

[norbitonflyer]

I seem to recall the different control voltages was why there are two subclasses of Class 09 conversions.

Those diagram books show the EE engine was 400hp in classes 08, 09 and 13, but 350hp in the older pre-nationalisation types (classes 11 and 12). The Blackstone (class 10) and Crossley engines are also shown as 350hp

 

[Dunfanaghy Rd]

08288 arrived at the Mid Hants in 1984 with (very tired) lead-acid batteries. It is a 90v m/c.
Pat

 

[Merle Haggard]

From memory, 90v & 110v. I'm not sure if this corresponded with a different battery type, but 75 NiFe cells at 1.2v each gives 90v. Did the 110v examples have Lead Acid batteries?

Tangentially, I remember that some DE shunters had the louvre vents in their battery boxes modified (e.g., plated over with smaller vents or hole cut out). I wonder whether this was due to being fitted with NiFe batteries - I don't know what NiFe batteries emit under charge but possibly not as dodgy as H2 and 02 in explosive proportion.

 

[Richard Scott]

Not quite - the article specifically states:

At the design stage it was agreed to install the established English Electric six-cylinder 6K power unit for this fleet, set to deliver 350-400hp

Surely it wouldn't be a random value between 350hp and 400hp? An 'established' engine design would have an established and fixed power rating.

Diesel engines often can vary depending on who and where they were set up. In works probably done reasonably precisely but on depot not always the case. Anyway 08/09s had no load regulator so getting optimum power to the wheels was not easy, in reality so a variation in power output was unlikely to be noticed in reality.
Just as an example of variations 50s could often vary a lot, nominally 2700hp but some reputed to have been set up on depot and producing a little over 3000hp. Have heard of a not particularly healthy one being as low as 2200hp so variations in 08/09s highly likely with their infrequent works visits.

 

[Irascible]

some reputed to have been set up on depot and producing a little over 3000hp

Yikes. Sounds a recipe for a dead generator...

 

[Richard Scott]

Yikes. Sounds a recipe for a dead generator...

It certainly was! Think generally the generator survived only because ETH was taking a few hundred hp!

 

[12LDA28C]

Yikes. Sounds a recipe for a dead generator...

More likely fried traction motors and electrical systems

 

[Clarence Yard]

On a 50 it will be a dead generator! The KV10 will allow it to happen and it will be fizz, bang, spizzle.

 

[saddlestoneman]

Many thanks for the contributions to the 350/400hp debate. I think it's clearer in my mind now that both figures are correct, depending on exactly when you classify the locos, ie they were built with a 350hp rating (probably at 600rpm), and then once the non-EE engine/transmission examples were withdrawn, the whole class could be uprated to 400hp at 680rpm.

Still sticking to the 08s, but on a slightly different subject: how were the new locos transported to their new sheds once they had been outshopped from Crewe, Derby, Darlington, Doncaster and Horwich? They were allocated all over England, Wales and Scotland, seemingly with no thought as to the distance to the shed. For example some Horwich locos made their way to St Blazey in Cornwall. Would they have made the long journey under their own power, or in goods trains, presumably with their coupling rods removed?

best regards .. Stef

 

[DustyBin]

Still sticking to the 08s, but on a slightly different subject: how were the new locos transported to their new sheds once they had been outshopped from Crewe, Derby, Darlington, Doncaster and Horwich? They were allocated all over England, Wales and Scotland, seemingly with no thought as to the distance to the shed. For example some Horwich locos made their way to St Blazey in Cornwall. Would they have made the long journey under their own power, or in goods trains, presumably with their coupling rods removed?

best regards .. Stef

I believe the rods needed to be removed for stability reasons, and the traction motors needed to be isolated (de-meshed is the correct term IIRC) so that they didn't over-speed. Even then I think they were limited to 45mph, but I could be mistaken!

 

[reddragon]

The earlier locos were 90V, rated at 350hp and were generally rated as 15mph. BR withdrew most of these by the early 1980s, 08001-387 I think.

Later locos appear to be 110V rated at 350hp & 15/20mph (08388 onwards), at some point rating from new seemed to increase to 400hp and 20mph, with earlier ones uprated later. The class 09s seems to be split between 350/400hp and all uprated.

Later impressions seem to be a mix of 08s rated at 350/400hp and 15/20 mph based on local needs. I don't think that there is a definitive answer and change happened often

With the Routemaster bus the AV590 engine had different ratings for the RM, RML and RMC whilst the bigger AV690 had different ratings for the RM, RML, RCL, RMA and RMF. The garage could change this on a whim and did in later years.

Even before engine management systems, power & torque outputs could be changed. I remember a London Transport Leyland Titan number T52. The local garage uprated the Gardener engine from 150hp to much more to use on the 175A route and to see what happened, based on their coach Titans. It increased its speed from 40 to 70mph, you could wheelspin it in the wet. The engine blew up after about a year in service!

So any 08 could be rated at 350/400hp or somewhere in between or near. I never understood the 15mph limit that also applied to the class 13 as the gearing and max rpm were the same. I assume a preservationist can make that choice when setting the governor & fuel pump.

 

[D365]

It reads to me like some parties are more liberal about the power calibration settings than others!