Cummins powered vehicles versus the rest

[cav551]

Since other threads have been constantly sidetracked by comparisons with ■■■■■■■ engines maybe we could transfer our thoughts here. So to kick off a few quotes from the Leyland Marathon thread.

Compare the ■■■■■■■ 12 and 14 litre six cylinder engines with any competitor, but please try to keep the comparison limited to the direct competitors of a particular time period and of broadly similar cubic capacity.

Carryfast said:

"It’s obvious that running the ■■■■■■■ at its peak power or for that matter even at lighter load than that at 2,000 rpm + would have massacred the fuel consumption figures.

Carryfast said:

"While the fact that driving the thing in the wrong gear at the wrong engine speed and/or making unnecessary use of all the available power at any point,while not making correct use of the available torque,is the point ‘if’ someone was actually setting out with the aim of artificially creating a worse journey time/fuel consumption figure v the TL12.As would making a pointless irrelevant comparison of the TL12’s v the ■■■■■■■■ piston speeds at an equally irrelevant equivalent high idle speed.

While we’ve already got documented evidence that even the road test regime only started to supposedly realise and apply the technique of ‘letting the ■■■■■■■ lug’ with the introduction of the BC.When the SC’s obvious real world working rev range was between 1,350 rpm - 1,800 rpm with absolutely no need to take it above 1,800 rpm for an easy 300 + hp by just a quick glance at the torque and SFC curves.Again that unbelievable erroneous inference,of it supposedly being ok to rev the nuts of the SC,being more explainable by conspiracy than ■■■■ up.While the type of driver who wants to thrash a motor way outside of its optimum operating range will get bad fuel consumption figures regardless of the engine type."

Railstaff said
“The small cams made peak power at 2100 rpm.

A spirited driver could drop an SC to 5mpg.They hammered fuel,one reason as ive explained of the adoption of big cam.
Another issue which ive never mentioned is the power and torque outputs were very inconsistent,and this is still more true today of the electronics.”

(zb)Anorak said:

“I think I’ve read elsewhere that the 14 litre ■■■■■■■ needed regular “tuning” to release its potential, otherwise its performance and fuel consumption were below par.”

Railstaff said:

“That is correct,■■■■■■■ advised two top sets a year if engine under hard use,that means double shifted or an hours based schedule.

Taking the covers of an 855 without training in 1972/3 would have been daunting to the average fitter.There was so much to take in, using the timing marks on the auxhillary drive,then of course the three different methods of setting the injector preload,IBC,OBC,DTI.The adjustment of the fuel pressure on a snap reading,you had to have a degree in brain surgery to maintain them.Things got left understandable,but yeah when on song they flew or maybe in reality could be made to fly.”

Dave Docwra said:

“Going back a year or two I worked for a company who run a mixed fleet of British vehicles & three 2800 DAFs, my experience at the time with the fleet was that the ■■■■■■■ powered vehicles were reliable & we did have to do rebuilds on the engines which were pretty much straight forward, The Rolls Royce diesel engines took much more time to rebuild & were done more often, The Gardner 240s or as some people describe them boat anchors, only ever needed exhaust (bag pipes) down pipes replacing & as far as I can remember we never rebuilt one, the two Marathons we had, were reliable and only one of them had a head gasket replaced which was on the one which was driven by a racing driver who never quite understood it was a truck”

[carryfast]

We’ll first need to bust a few myths and set a few rules and examples of exceptions which proved rules.

The relevant comparison regarding piston speed is piston speed at the equivalent output not the equivalent engine speed.Which added to the issue of leverage at the crank makes the choice between longer stroke ( ■■■■■■■ ) v shorter stroke ( TL12 ) a no brainer.

The Gardner 240 was arguably a better more efficient engine than an NA ■■■■■■■■■■ was also the NA exception which showed that a good NA engine can compete with a bad turbocharged one ( TL12 ).

The Detroit 92 series was anything but a high revving screamer and was in fact a natural rival to the ■■■■■■■■■■■■ it had been given a fair chance in the Bedford TM soon enough virtually from the start.

The SC let alone BC ■■■■■■■ was more than capable of dealing with anything which the Europeans could throw at it.However that was obviously dependent on correct gearing and driving methods in that just as today drivers need to keep the engine within a clearly defined rev range wherever possible.Usually now denoted by the ‘green band’ on the rev counter but not always then but obviously no excuse for media road testers in the day nor operators not being strict with their drivers in that regard.Peak power being effectively irrelevant in that and torque being the relevant benchmark in providing more power for any given engine speed.Which again made the choice between 335 let alone 350 ■■■■■■■ v TL12 a no brainer.

As for the admittedly relatively complicated PT injection systems,on both ■■■■■■■ and Detroit types,operators wouldn’t/shouldn’t have automatically expected to take the things either to the truck main agent or independent garage or their own maintenance staff and get the correct technical back up that was available from the dedicated engine specialists.In the case of Detroit at least from experience of sometimes the need to set up new engines properly,let alone well used ones,that often meant taking them to Talbot Diesels for example who were a ( very good ) UK/European Detroit engine authorised agent.Not give it to someone who’s expertise was working on AEC engines or relying on the local Bedford agent or specialist independent to fix the things.

Should any of that have counted against them no.Bearing in mind that the average in house or independent workshop operation would probably have had similar issues in dealing with the different idiosyncrasies of numerous different types.Especially later with the introduction of OHC/CIH in which I’d guess the average Detroit 60 series,let alone N14,specialist wouldn’t know where to start if given a ■■■■■■■ ISX or Volvo D13 etc to fix.Ironically the flexibility of having a specialist loose engine agent network possibly being better than expecting every main agent to be expert in fixing in house engine problems.

[railstaff]

Although as said on the Marathon thread that the TL12 was more than up to the job,it is quite challenging to think of a EUROPEAN engine back then that could actually out perform a standard from factory high horse power 855.Of course if played with there is none.But my two candidates are-

Fiat 8280

Scania DS14

[james_908]

Carryfast:
We’ll first need to bust a few myths and set a few rules and examples of exceptions which proved rules.

The relevant comparison regarding piston speed is piston speed at the equivalent output not the equivalent engine speed.Which added to the issue of leverage at the crank makes the choice between longer stroke ( ■■■■■■■ ) v shorter stroke ( TL12 ) a no brainer.

The Gardner 240 was arguably a better more efficient engine than an NA ■■■■■■■■■■ was also the NA exception which showed that a good NA engine can compete with a bad turbocharged one ( TL12 ).

The Detroit 92 series was anything but a high revving screamer and was in fact a natural rival to the ■■■■■■■■■■■■ it had been given a fair chance in the Bedford TM soon enough virtually from the start.

The SC let alone BC ■■■■■■■ was more than capable of dealing with anything which the Europeans could throw at it.However that was obviously dependent on correct gearing and driving methods in that just as today drivers need to keep the engine within a clearly defined rev range wherever possible.Usually now denoted by the ‘green band’ on the rev counter but not always then but obviously no excuse for media road testers in the day nor operators not being strict with their drivers in that regard.Peak power being effectively irrelevant in that and torque being the relevant benchmark in providing more power for any given engine speed.Which again made the choice between 335 let alone 350 ■■■■■■■ v TL12 a no brainer.

As for the admittedly relatively complicated PT injection systems,on both ■■■■■■■ and Detroit types,operators wouldn’t/shouldn’t have automatically expected to take the things either to the truck main agent or independent garage or their own maintenance staff and get the correct technical back up that was available from the dedicated engine specialists.In the case of Detroit at least from experience of sometimes the need to set up new engines properly,let alone well used ones,that often meant taking them to Talbot Diesels for example who were a ( very good ) UK/European Detroit engine authorised agent.Not give it to someone who’s expertise was working on AEC engines or relying on the local Bedford agent or specialist independent to fix the things.

Should any of that have counted against them no.Bearing in mind that the average in house or independent workshop operation would probably have had similar issues in dealing with the different idiosyncrasies of numerous different types.Especially later with the introduction of OHC/CIH in which I’d guess the average Detroit 60 series,let alone N14,specialist wouldn’t know where to start if given a ■■■■■■■ ISX or Volvo D13 etc to fix.Ironically the flexibility of having a specialist loose engine agent network possibly being better than expecting every main agent to be expert in fixing in house engine problems.

Not again

Sent from my SM-G900F using Tapatalk

[carryfast]

railstaff:
Although as said on the Marathon thread that the TL12 was more than up to the job,it is quite challenging to think of a EUROPEAN engine back then that could actually out perform a standard from factory high horse power 855.Of course if played with there is none.But my two candidates are-

Fiat 8280

Scania DS14

Ironically the question as to how many turbocharged Europeans could match let alone exceed the specific torque output of the SC 335 or 350 let alone 320 + BC,or the Detroit 92 series as opposed to how many were as low or lower as/than the TL12 might finally show that the TL12 was anything but ‘up to the job’.

The rest being history of sabotage in the Brits not taking full advantage of the former when in it mattered while deliberately crippling ourselves with the 71 series and the TL12.

[bewick]

James.908:

Carryfast:
We’ll first need to bust a few myths and set a few rules and examples of exceptions which proved rules.

The relevant comparison regarding piston speed is piston speed at the equivalent output not the equivalent engine speed.Which added to the issue of leverage at the crank makes the choice between longer stroke ( ■■■■■■■ ) v shorter stroke ( TL12 ) a no brainer.

The Gardner 240 was arguably a better more efficient engine than an NA ■■■■■■■■■■ was also the NA exception which showed that a good NA engine can compete with a bad turbocharged one ( TL12 ).

The Detroit 92 series was anything but a high revving screamer and was in fact a natural rival to the ■■■■■■■■■■■■ it had been given a fair chance in the Bedford TM soon enough virtually from the start.

The SC let alone BC ■■■■■■■ was more than capable of dealing with anything which the Europeans could throw at it.However that was obviously dependent on correct gearing and driving methods in that just as today drivers need to keep the engine within a clearly defined rev range wherever possible.Usually now denoted by the ‘green band’ on the rev counter but not always then but obviously no excuse for media road testers in the day nor operators not being strict with their drivers in that regard.Peak power being effectively irrelevant in that and torque being the relevant benchmark in providing more power for any given engine speed.Which again made the choice between 335 let alone 350 ■■■■■■■ v TL12 a no brainer.

As for the admittedly relatively complicated PT injection systems,on both ■■■■■■■ and Detroit types,operators wouldn’t/shouldn’t have automatically expected to take the things either to the truck main agent or independent garage or their own maintenance staff and get the correct technical back up that was available from the dedicated engine specialists.In the case of Detroit at least from experience of sometimes the need to set up new engines properly,let alone well used ones,that often meant taking them to Talbot Diesels for example who were a ( very good ) UK/European Detroit engine authorised agent.Not give it to someone who’s expertise was working on AEC engines or relying on the local Bedford agent or specialist independent to fix the things.

Should any of that have counted against them no.Bearing in mind that the average in house or independent workshop operation would probably have had similar issues in dealing with the different idiosyncrasies of numerous different types.Especially later with the introduction of OHC/CIH in which I’d guess the average Detroit 60 series,let alone N14,specialist wouldn’t know where to start if given a ■■■■■■■ ISX or Volvo D13 etc to fix.Ironically the flexibility of having a specialist loose engine agent network possibly being better than expecting every main agent to be expert in fixing in house engine problems.

Not again

Sent from my SM-G900F using Tapatalk

Unfortunately YES James ! I thought The Great Man of Leatherhead would maybe have “sworn” a new years resolution not to infect the various threads with his "verbal d " ( ■■■■■■ ) But NO he has decided to ignore/break the resolution he made at 1 minute past midnight 1/01/18 ! I’m still awaiting for him to deliver my Camembert and Rough Red from my Pal Fergie in Brittany ! it will be rancid and rotten by “CF” delivers the box, plus he might have relieved himself in the bottle but then again, French wine it might improve the taste so we won’t hold that against him ! As Dave won’t have spent anymore than 1Euro per 1ltr bottle Best Wishes for 2018 Dennis.

[bewick]

[bewick]

Rear shot of a fine 220 ■■■■■■■ engine Borderer showing the rear of the engine ( as opposed to the phantom shots of the rear of a Guy Big J /8LXB) this particular unit had the RTO 610 box and the Eaton 2 speed axle. It could ■■■■ all over 8LXB engined units and did quite often. I recall one instance when I was driving it north on the M6 I passed an 8LXB ERF ( I think it was) on the grade up past Wigan. I was fully freighted with 20 ton of woodpulp. Well I pulled onto Charnock and had got out of the cab when this Scotsman run across the Park and stuck his head into the back of the cab tunnel, he wouldn’t have it that it was a 220 ■■■■■■■ and I had to show him my notes before he accepted I was fully freighted, which anyone could see was fact ! He was one sick puppy ! He still couldn’t understand why I had walked past him ! I didn’t enlighten him as to the fact that the Atki had the Eaton 2 speed axle i.e. 20 gears one for every occaision ! Cheers Bewick.

[windrush]

As I said before, somewhere on here a lifetime ago now, we had two Foden eight leggers (a tipper and tanker) at our Tilcon plant with 250 ■■■■■■■ engines but I’m not sure what model of engine it would have been? They were on X and Y reg plates though if that helps at all. I did retorque the valves, crossheads and injectors on one using a little Snap On torque wrench and a DTI was also used, and its tip broke off and dropped into the sump! It stayed there as well. I can’t remember either engine ever being dismantled and one was in a powder tanker with a lot of blowing time as well. I think they were heavier on fuel that the Rolls 265L’s and Li’s but the tipper version was piloted by a driver with a heavy right foot anyway! The tanker had a steady old lad on it when new, another chap drove it afterwards, but blowing time would eat into the fuel of course. No more were purchased though so I’m guessing the Roller was the preferred option although travelling around the country other Tilcon depots had Fodens wearing the ■■■■■■■ badge.

I would have thought for road transport operators the ability to maintain their own fleet without having to call in expensive outside ‘technicians’ would have been the best option, simple engines like the Rolls, Gardner, Leyland etc would suit them better instead of the ■■■■■■■■ but of course nowadays such an engine doesn’t appear to exist anyway? Sorry if this doesn’t help answer any questions.

Pete.

[railstaff]

windrush:
As I said before, somewhere on here a lifetime ago now, we had two Foden eight leggers (a tipper and tanker) at our Tilcon plant with 250 ■■■■■■■ engines but I’m not sure what model of engine it would have been? They were on X and Y reg plates though if that helps at all. I did retorque the valves, crossheads and injectors on one using a little Snap On torque wrench and a DTI was also used, and its tip broke off and dropped into the sump! It stayed there as well. I can’t remember either engine ever being dismantled and one was in a powder tanker with a lot of blowing time as well. I think they were heavier on fuel that the Rolls 265L’s and Li’s but the tipper version was piloted by a driver with a heavy right foot anyway! The tanker had a steady old lad on it when new, another chap drove it afterwards, but blowing time would eat into the fuel of course. No more were purchased though so I’m guessing the Roller was the preferred option although travelling around the country other Tilcon depots had Fodens wearing the ■■■■■■■ badge.

I would have thought for road transport operators the ability to maintain their own fleet without having to call in expensive outside ‘technicians’ would have been the best option, simple engines like the Rolls, Gardner, Leyland etc would suit them better instead of the ■■■■■■■■ but of course nowadays such an engine doesn’t appear to exist anyway? Sorry if this doesn’t help answer any questions.

Pete.

Thats exactly how it was.People felt more relaxed and were more at ease fitting injection pumps which in hindsight didnt go wrong very often compared with checking fuel pressures,setting valves,crossheads,injector preloads and if you were really lucky jake brake clearances.Quite simple if you were doing it every day of the week,mind boggling if you were not.

[carryfast]

Bewick:
0
Rear shot of a fine 220 ■■■■■■■ engine Borderer It could ■■■■ all over 8LXB engined units and did quite often.

Blimey anyone can do the less power it’s got the faster it goes.But some say the TL12 Marathon could be in two different places at once depending on who road tested it.

[cav551]

The ■■■■■■■ engine probably woke up some people to the fact that here was a diesel engine which you could actually ‘tune’. Most times it was really finding out that you needed to do so rather than wanted to do it.
As has been said they did tend to ‘go off’ after several thousand miles and require the injectors and valve clearances reset. There would either be a complaint of lack of power or of blacking. This was in reality quite a simple job - if you had the right tools to do it and these were in good condition - and of course the vital factor getting to do it frequently enough. The recommendation from ■■■■■■■ seems at this distance to have gone through more than one period of changing their mind about whether the OBC or IBC method was to be used. There was a lot more that you could do as well if the aim was to improve performance and you had the gear to do it.

These were also the first engines to provide a rude awakening about the effort required to torque down the head bolts especially the 12 litre 205 and 220 when in a fixed cab. Like most engines they had their faults; some quite annoying like manifold bolts sheared off level with the head and injector sleeves which leaked fuel into the coolant. Compared to some makes were not so easy to carry out a routine service, the spin on filters often seemed to be araldited in place or if the element type was fitted then they were normally caked in mud and road dirt. Anyone else remember the red and green liquid DCA test kit?

[gingerfold]

Never recall any issues with the 14 litre ■■■■■■■ powered trucks in the fleet I was responsible for and the “top end overhaul”, as we called it, kept them in fine fettle. High mileage, bomb proof (and driver proof) engines that set the benchmark for long life, and trouble free running. Now the 10 litre ■■■■■■■ wasn’t quite in the same league as its bigger cousin.

[railstaff]

The change in method came about really due to the trouble the 743(sc) had with cam bushs spinning in the block.■■■■■■■ came up with the idea of setting the injector preload of the “cam”(ibc) would be better,7lbs in as against 65lbs in.In reality it didnt fix it.Alas big cam.The method that seemed to have the most consistant results was DTI because this catered for an injector with a weak or over strong return spring.

[jelliot]

I’ve driven quite a few trucks that have been shoved down the road by Cunnims… Detriot … Cat … Volvo… Isuzu… Scania … Merc… What usually happens is I turn up for work in the morning and the boss says take that one over there, as he points vaguely at a truck. He doesn’t give a rats ■■■ what truck it is, and I get paid exactly the same amount of money regardless of what I drive. And that’s about as much say in it as I get…

We have a few ■■■■■■■ powered Kenworth that get along pretty good, some have the speed limiter set to 99k’s which is a bummer… My old interstater with a Detroit 60 in it would happily get along at 106 all day, but doesn’t pull to well on hills… Well I say doesn’t pull very well but most of the time it’s about 65 to 80 tonnes and pulling 9 axles or 12 of drag. By the time your out through the hills section our ■■■■■■■ Kenworths are a couple of k’s in front… It’s just the way the computer is set on them now a days. I get passed by as many Detroit powered trucks as I get by ■■■■■■■ and Cat… I don’t count any one that’s only pulling one trailer or as we call them “Half a truck”

My sister used to work at ■■■■■■■ research and development when she left uni… she was a number cruncher, and said the best thing about working there was the canteen, She’s now an accountant at KPNG and says the food there is crap compared to ■■■■■■■■

Also interesting to note… all the time I’ve been driving in Australia no one has ever mentioned fuel consumption…I know that if I trip the computer on some of the hills I go up it’ll show something around 640 meters to the litre… I think the lowest I’ve had it was 150 meters to the litre… Groovy …

Jeff…

[newmercman]

I’ve driven a few lorries with ■■■■■■■■ E290s, an L10 and an M11, the E290 was a decent enough engine, probably the best puller in the 270hp to 300hp class. The L10 was not so strong obviously, but it was much better on fuel. The M11 was a very good engine, decent power and outstanding fuel economy, just a shame it was in chassis (ERF, Foden and Seddon Atki) that were nowhere near as nice to drive as the competition.

The current model ISX, I wouldn’t have one as a gift, a true boat anchor in my opinion.

Sent from my SM-G950W using Tapatalk

[jelliot]

We have a couple of the newer ISX, the head mechanic recons we should keep them going at around 1500 to 1750rpm for climbing, and keep the revs up for the engine brake… The only reoccurring problem we had was blowing the ERG hose that runs round the back of the engine. But that could have something to do with the way the exhaust is routed.
I haven’t driven one for a while but if I remember right they sit at about 1550 rpm at 100kph… which isn’t to bad… Over an 1100 k run @ 60+ ton they’re only a few minutes behind the Detroit’s and Cats we run… I think most of ours are set at either 650 or710 bhp, not sure about the torque.
For ■■■■■■■ I prefer the Signature…
I heard an old White Road Boss the other day that had a two stroke Detroit in it running straight through exhaust stacks… Do I need to finish this sentence… Groovy …

Jeff…

[erf-ngc-european]

Coincidentally, DEANB has just posted an article about a UK (imported) KW K100E on the Heavy Haulage thread. It is a standard K100E 6x4 unit but, intriguingly, it has a ■■■■■■■ NTC 400B lump (delivering an alleged 600bhp) with a Fuller RT 11509 box. Now then, I’ve looked askance at the old K100E before - even sat in one once and wondered how uncomfortable it might be - but I might just have put up with this one in the late '70s (yes, it’s on a W-plate).

Here’s the link! Robert

viewtopic.php?f=35&t=147350&start=1260

And here’s the cover page:

[windrush]

As somebody mentioned the L10 I did have some experience of those. First one was fitted in an A reg Foden eight legger at Tilcon, I was in the garage back then and was told to collect this brand new truck from our Reddish depot. It seemed to livelier that the 201 Gardner and when I landed back at the quarry the TM came out to admire it! Coincidentally a ■■■■■■■ mechanic was there sorting out an erratic running 250 in our tipper under warranty (traced to a porous fuel line from tank to pump) and came over to have a look. “A load of crap, get rid of it” he told the TM! So it was sent to our quarry near Kington and got through a few engines! However it did return, our storeman bought it and became an O/D and it did good work, eventually my gaffer bought it from him and ran it for a while as well.

I drove two Foden six wheelers with 250 L10’s for five years, I found they had no low down pulling power and leaked oil worse than a Gardner but they did keep going, however there were several Ford Cargos at the quarry with the same engine and Jake brakes fitted and they really flew! Presumably better geared than the Fodens? I replaced the water pumps on both of ours, a fiddly task!

One interesting thing about the older ■■■■■■■ 250’s we had, not the L10’s, was that they came new with exhaust brakes fitted by Fodens. ■■■■■■■ refused to warranty the engines unless they were removed and many years later, when I drove the L10’s, Fodens still fitted a similar brake and they also had to be blanked off!

Pete.

[zb_anorak]

cav551:
The ■■■■■■■ engine probably woke up some people to the fact that here was a diesel engine which you could actually ‘tune’. Most times it was really finding out that you needed to do so rather than wanted to do it.
As has been said they did tend to ‘go off’ after several thousand miles and require the injectors and valve clearances reset. There would either be a complaint of lack of power or of blacking. This was in reality quite a simple job - if you had the right tools to do it and these were in good condition - and of course the vital factor getting to do it frequently enough. The recommendation from ■■■■■■■ seems at this distance to have gone through more than one period of changing their mind about whether the OBC or IBC method was to be used. There was a lot more that you could do as well if the aim was to improve performance and you had the gear to do it…

Was it the case that other engines, without the fine adjustment facilities, just worked less well, or was the ■■■■■■■ more prone to going “off”, so requiring the extra controls?