AEC V8

UK PROFESSIONAL DRIVERS FORUMS OLD TIME LORRIES, COMPANIES AND DRIVERS (INTERACT
41

Bewick:

Riverstick:
So…did Guy actually fit the ■■■■■■■ V8 for a short production run?..My father tells me they did a V8 of some make and were immensley troublesome.

I believe it was the ■■■■■■■ V6 that Guy used for a short,disasterous,period when the Big J was first launched.Cheers Bewick

Yes, it was the ■■■■■■■ V6 in the Guy Big J. The same engine was also used in the Dodge 500 series tractor unit (along with the ■■■■■■■ V8 in some models). We had a Ford D Series tractor unit with a ■■■■■■■ V8 at Mothers Pride, which went like the proverbial, because we always ran below maximum GVW. I recall that it didn’t give much trouble but used plenty of diesel. We had an odd trunking fleet at Mothers Pride, ranging from the aforementioned Ford (and I liked the D Series range) to Gardner powered Seddons and ERFs, and virtually every make in between.

42

[zb]
anorak:
Some of the previous posts may give a hint- both AEC and ■■■■■■■ VINE V8’s were short-stroke screamers, by lorry standards. They were prone to driver abuse. They were designed to get more power out of a given engine size by the use of high engine speeds. The tuning of the inlet and exhaust would be optimal at these higher speeds, at the expense of lower-speed torque, meaning that, for the engine to provide the power in service, it would need to run faster, on a lower gear ratio. I think that this is the crux of it, assuming that the AEC’s problems with cooling and bearing wear were surmountable. Other makes, notably Unic and Fiat, built reliable oversquare V8’s, but with lower governed speeds. Mercedes OM400s and Deutz 413s were high-revving engines, but not to the extent of the ■■■■■■■ and AECs. If there is one over-riding factor which links the two engines, it is their unusually high governed speed. Berliet’s original 12.8 litre V8 was also a dud, and they solved the problems by making it a 15 litre and reducing the governed speed of it.

^ This.
It’s all about getting the overall capacity,number of cylinders,stroke measurement and therefore engine speed equation right.

43

Evening all, my personal experience of the V6 ■■■■■■■ was (luckily), limited to one example in a Big J. Now I quite liked the big Guys, (less so the Thornycroft Gearbox in the ■■■■■■■ powered ones),but all in all a nice lorry. Perhaps less so the beautiful looking, but Orrible to drive 150 Gardner powered Invincibles, but one day I had a rush of blood to the head and ended up with the V6 Guy…what a lemon!!

Eventually a buyer from a sunny climate decided that he would accept it…for there was no other way that I would let him have the other vehicles that he wanted, so off to Tilbury she went, and each time I glanced in my mirror she looked rather sad sat up there on the trailer! Unloading, no problem, she cracked up straight away, I could not believe it. Then crossing a rail line, she stopped,not even a falter…just silence.But I was not to be beaten, her compatriot on my trailer dragged her to her parking place, I had learned the danger and difficulty of the Big Js tilt cab mechanism, so would have no truck with even attempting to use it!

The only V8 Mandators that I have personal experience of, were the example operated by Chris Foster at Dudley, and maintained by the late Johnny Yapp. These ,as Trev H says worked very hard, but I recall Johnny used to drop oil and filters, (and sometimes change shells) at circ 25000miles. But in their day were spectacular performers. And of course there was the 8x4 Coles operated by Longton crane hire, fitted with an AEC V8, that always seemed to be on the go! Wonder what happened to her?

Cheerio for now.

44

Yes Saviem, we tend to forget the industrial versions of AEC engines and there certainly was a range of AEC V8 industrials produced. Likewise the industrial AEC AVT 1100s of which several are known still to exist. Some are in a pumping station near Aylesbury, some at Ferrybridge power station used as start-up / standby units, some at power stations in Ireland, at least one as a reserve generator in the basement of the London City offices of one of major high street banks, and several are rumoured to be in Government buildings such as the MoD, again for emergency generating purposes.

45

Are any of the AEC V8 generating sets still in use, or available to be used if needed?

46

I don’t know, but it’s surprising what turn up from time to time. There are still AEC engines in MoD reserve stores and a couple of AV760 units, ex-MoD, were auctioned in Lincolnshire about 6 weeks ago.

47

Saviem:
Evening all, the AEC V8s, a subject quite near to the heart of this “Francophile”, particularly as I saw file notes relating to France`s Willemes desire for closer, (read integration), co-operation with AEC, from 1960. This when I was sorting through assorted documents concerning Willeme, prior to their demise, and the licence agreement with Perez et Raimond for the construction of the heavy range of Willeme tractors, (150/1000tonnes).

Could the origin of the V8 have been in AECs desire, not to loose a major customer for its "loose " engines, that is Wolverhamptons Guy Motors, then under the ownership of messers Jaguar?

Jaguar/ Guy, were in the throes of a potential collaboration, and licence deal to build at the adjacent Henry Meadows works, (remember those loose fabric belt drives), a version of the USAs Mister ■■■■■■■ V profile diesel engines.

To set the context for this scenario let us remember dear Barbara Castle`s 1964 Construction and Use Regulations. 16tons on two axles, 22tons for threeaxle articulated and rigid machines, and 32tons for four axle rigid and articulated machines, (dependant on wheelbase). All subject to a 40mph limit on non Motorways, and 60mph on Motorways.

Jaguar management were anxious that Guy were at the cutting edge of HGV design and engineering, and they proposed a new range of Jaguar inspired lorries, the Big J, (Jaguar). Sankey of Telfords design for a uprated LAD style cab had been rejected by Jaguar management, even though a "refined " Invincible chassis had been equipped with such a driving enviroment by the Fallings Park “Experimental Department”.

But Coventry , (and a Rubery Owen Group Company), Motor Panels design won favour, particularly when the Fallings Park draughtsmen created a destinctive front panel treatment to set it apart from those utilised by Seddon, Floor, and ERF. The only design hange made was to replace the “mini” Feathers in our cap Indian head with a J symbol!! (Jaguar rules)!

But Jaguar / Guy envisaged a flat floor, tilt cab, high power design, and the compact dimensions of the ■■■■■■■ V series suited perfectly…and the adjacent Meadows manufacturing site was a perfect platform to manufacture under licence a “orld series” design engine range.

With hindsight we can all see the engineering, and manufacturing, and operating problems…but we are not in the 60s!!!

AEC were a major “loose engine” supplier in their own right, and Wolverhamptons Guy, a major customer to AEC during the 60s.

Guys old works manager, John Bowley, had moved to Southall as AECs General Manager.And he maintained close links with his old colleagues at the Jaguar/ Guy, and was horrified to learn of Jaguars plans to adopt, “in house” the products of a major US manufacturer. Was this the ultimate “driver”, of the effort that AEC put into creating the V series■■?

Think about it…their major loose engine customer was about to introduce a new range of “premium” chassis, all with a flat floor, tiltable cab. Not suitable for the “current” vertical 6cylinder configurations…so they were going to licence build a “state of the art” US design, “in house”…what would you do, if confronted by a potential 30% loss of business…you would ,(as AEC) try to match it.

So the AEC V8 was created, but with great difficulty, as ■■■■■■■ had a range of restrictive patents covering the V configuration. So the AEC V was created , initially at 740, then 800 cubic inches. BUT, created not for AEC initially, but for Jaguar/ Guy, and the new Big J range!!

But whil`st this “normal” business activity was taking place…along came Leyland, and the takeover/merger.

Now on another thread there has been extensive writing about the Fixed Head Leyland designs, from 700, down to 400 cubic inches, and this is not the place to comment on those writings, but that the enlarged grouping of AEC and Leyland saw the V design eventually under he most excellent Ergomatic cab is a fact. That the design lacked cooling capacity, again is a fact, (for it was designed for an installed enviroment with a far larger cooling capacity is again fact, (and I cite also the “experimental” Motor Panels designed AEC VT trial vehicle, perhaps a rival to Jaguars Big J).

That the Big J ■■■■■■■ V venture was a failure, there is no doubt. That the fear of it working drove AEC into designing the V8, well that is open to debate, and the fact that the Leyland intervention “mudded” everything…well that must be pretty certain! But that engine was never designed to sit under an ergomatic cab, that must be fact!!!

Adieu mes Braves, Cheerio for now.

I`ve read this somewhere before Saviem ,that a AEC manager had been visiting GUY for a routine visit and noticed a V engine there from ■■■■■■■ and on his return to Southall ordered that a new V8 engine should be designed and built

48

gingerfold:
…did something change in the design of the engines from prototype stage to full production when the model was launched? Did Leyland change the spec of some components to save money and that made it unreliable? Sadly, we will never know.

There is no reason why we cannot find out.
One of the ‘Four Rocker Cover’ prototype engines still exists, and is currently being stripped and rebuilt by a Lincolnshire enthusiast, with the eventual aim of getting it running.

Boon’s of Whittlesey ran both a production engine and a prototype in their V8, the prototype engine still being fitted when the lorry was taken out of service in 1978. The prototype unit was acquired via AEC Nottingham, and was rebuilt and swopped with the lorries original production unit at major overhauls (50’000 miles rings a bell). They always maintained that there was nothing to choose between them, with both units returning almost identical reliability in service. They did always fit the later fuel injection pump though, as they said it governed better with it fitted.

49

There does seem to be some similarities between the AEC V8 and the Leyland 500 ‘Headless-Wonder’ in that if you got an engine that was right then it was reliable and gave operators a normal service life-span. Sadly, for whatever reason there were too many ‘rogue’ engines that trashed the reputation, and there were far more Leyland 500s than AEC V8s. The Turners prototype completed about 300,000 miles with them and was sold to an owner driver at Wisbech who ran it for some considerable time. It was reputed to end up in Rush Green motors (verified by the owner of Rush Green) but I could never find it there.

50

With so much potential and rave reviews on its performance why didnt another manufacturer buy the rights to it and make it work a bit like Daf did with the 680 ,Leyland could have thrown Aec in as a sweetner .Its amazing that the government never stepped in and broke BL up and maybe backed the profitable companies instead of throwing money into a bottomless pit.Privatisation was the name of the game when Maggie became PM its a shame she didnt get into power 10 years earlier

51

ERF:

[zb]
anorak:
Were they dry liners, then?

Yes, they were ‘top hat’ design dry liners in both capacity engines.

Do you reckon, having looked at the cylinder block and liners, that it could have stood another increase in the bore, without making the liners or the walls of the block too thin? If it could have been stretched to 14 litres, I think it might have been worth Leyland carrying on with it.

52

[zb]
anorak:

ERF:

[zb]
anorak:
Were they dry liners, then?

Yes, they were ‘top hat’ design dry liners in both capacity engines.

Do you reckon, having looked at the cylinder block and liners, that it could have stood another increase in the bore, without making the liners or the walls of the block too thin? If it could have been stretched to 14 litres, I think it might have been worth Leyland carrying on with it.

In which case you’ve still got a high revving even more oversquare engine with the same excessively short stroke measurement.What was needed was an engine with a better stroke measurement than the 800 etc series if they had to have a V8.In which case the AEC 800 etc series just wasn’t up to the job in just the same way that the ■■■■■■■ 903 wasn’t.The surprising thing is how that wasn’t realised,in the case of the AEC V8 800 etc series,from the outset.

53

Carryfast:

[zb]
anorak:

ERF:

[zb]
anorak:
Were they dry liners, then?

Yes, they were ‘top hat’ design dry liners in both capacity engines.

Do you reckon, having looked at the cylinder block and liners, that it could have stood another increase in the bore, without making the liners or the walls of the block too thin? If it could have been stretched to 14 litres, I think it might have been worth Leyland carrying on with it.

In which case you’ve still got a high revving even more oversquare engine with the same excessively short stroke measurement.What was needed was an engine with a better stroke measurement than the 800 etc series if they had to have a V8.In which case the AEC 800 etc series just wasn’t up to the job in just the same way that the ■■■■■■■ 903 wasn’t.The surprising thing is how that wasn’t realised,in the case of the AEC V8 800 etc series,from the outset.

Oh noooooooooooooooooooooooooooooo :cry:

54

ramone:

Carryfast:

[zb]
anorak:

ERF:

[zb]
anorak:
Were they dry liners, then?

Yes, they were ‘top hat’ design dry liners in both capacity engines.

Do you reckon, having looked at the cylinder block and liners, that it could have stood another increase in the bore, without making the liners or the walls of the block too thin? If it could have been stretched to 14 litres, I think it might have been worth Leyland carrying on with it.

In which case you’ve still got a high revving even more oversquare engine with the same excessively short stroke measurement.What was needed was an engine with a better stroke measurement than the 800 etc series if they had to have a V8.In which case the AEC 800 etc series just wasn’t up to the job in just the same way that the ■■■■■■■ 903 wasn’t.The surprising thing is how that wasn’t realised,in the case of the AEC V8 800 etc series,from the outset.

Oh noooooooooooooooooooooooooooooo :cry:

Oh yes. What a shame. :imp:

55

Looking at the bore / stroke dimensions again then it was too much of an ‘oversqure’ design, but that was the perceived wisdom and fashion of the time amongst several engine designers. The theory of ‘oversquare’ was good, but the practice was not with the available technology of the time. Probably a more viable option for the V8-800 would have been to reduce the maximum rpm and turbo-charge it to get the power. I don’t think there was an issue with head gasket failures with the V8, and then again as I wrote previously the prototype engines which were trialled in the UK, Australia, South Africa, and Finland (Vanajan) did perform well, as did those in the AEC works transport fleet. Harry Pick, former AEC Depot Manager at West Bromwich (and later British Leyland at Oldbury) told me that if a spare part was urgently required from Southall then before the works transport Mandator V8’s said spares would be despatched in a van or car, but when a Mandator V8 was doing the the night spares trunk from Southall the urgent parts were sent with the V8 because it got there just as quickly as the van or car. Someone who worked for the Ricardo engine consultancy was convinced that the piston speed of the V8 was right on the limits of what was achievable reliably at the time, but I didn’t understand what he was on about as I’m not an engine designer. I still think something changed from prototype design to production that caused the problems. Maybe it was the re-design from Metric to Imperial, or vice-versa but I don’t want to get into Mike Knowles’ territory. :confused: :confused: :blush: :blush:

56

gingerfold:
Looking at the bore / stroke dimensions again then it was too much of an ‘oversqure’ design, but that was the perceived wisdom and fashion of the time amongst several engine designers. The theory of ‘oversquare’ was good, but the practice was not with the available technology of the time. Probably a more viable option for the V8-800 would have been to reduce the maximum rpm and turbo-charge it to get the power… Someone who worked for the Ricardo engine consultancy was convinced that the piston speed of the V8 was right on the limits of what was achievable reliably at the time…

The fashion of the 1960s was to try high engine speeds as a means of increasing the power for a given capacity/package size/weight/manufacturing cost. It caught a few designers out, notably AEC, ■■■■■■■ and Berliet, although the Germans seem to have known just where the limit was, and governed their ambitions accordingly. I apologise for the dreadful pun. Some posters have touched on the variability of the AEC’s governed speed, with reference to injection pumps- I wonder if the good/bad engine conundrum has something to do with that? Whatever, excessive speed seems to have been the culprit, so what you say makes sense. However, at 13.1 litres, it was still too close to the TL12. To give it a chance, it would have had to displace the ■■■■■■■ NTC335 from the Marathon, which is why I asked about the viability of a further increase in capacity.

With a capacity of 14 litres, longer inlet tracts, a 4-2-1 exhaust manifold like the Scania DS14 and a small turbocharger, 320bhp at 2200rpm would have made the AEC a competitive engine for the early 1970s. It might have needed a higher flow-rate water pump, and the Marathon cab gave enough space for a huge radiator. All that remains is those too-small big-end journals…

57

[zb]
anorak:

gingerfold:
Looking at the bore / stroke dimensions again then it was too much of an ‘oversqure’ design, but that was the perceived wisdom and fashion of the time amongst several engine designers. The theory of ‘oversquare’ was good, but the practice was not with the available technology of the time. Probably a more viable option for the V8-800 would have been to reduce the maximum rpm and turbo-charge it to get the power… Someone who worked for the Ricardo engine consultancy was convinced that the piston speed of the V8 was right on the limits of what was achievable reliably at the time…

The fashion of the 1960s was to try high engine speeds as a means of increasing the power for a given capacity/package size/weight/manufacturing cost. It caught a few designers out, notably AEC, ■■■■■■■ and Berliet, although the Germans seem to have known just where the limit was, and governed their ambitions accordingly. I apologise for the dreadful pun. Some posters have touched on the variability of the AEC’s governed speed, with reference to injection pumps- I wonder if the good/bad engine conundrum has something to do with that? Whatever, excessive speed seems to have been the culprit, so what you say makes sense. However, at 13.1 litres, it was still too close to the TL12. To give it a chance, it would have had to displace the ■■■■■■■ NTC335 from the Marathon, which is why I asked about the viability of a further increase in capacity.

With a capacity of 14 litres, longer inlet tracts, a 4-2-1 exhaust manifold like the Scania DS14 and a small turbocharger, 320bhp at 2200rpm would have made the AEC a competitive engine for the early 1970s. It might have needed a higher flow-rate water pump, and the Marathon cab gave enough space for a huge radiator. All that remains is those too-small big-end journals…

So why didn`t someone try to put these improvements into place or do you think it was big brother holding them back?

58

ramone:
So why didn`t someone try to put these improvements into place or do you think it was big brother holding them back?

There probably wasn’t enough meat in the bores to allow a further increase in capacity. That is why I asked Mr. ERF whether he thought it was possible.

The other possible reason is that Leyland realised it had bitten off more than its design capabilities could chew, having made a mess of the V8 and the 500. Even if it could retain some faith in its engineers to make the design competitive, the shopfloor could not, at the time, be trusted to build the things with anything like proper quality control. Buying in the 14 litre ■■■■■■■ would undoubtedly dent Leyland’s profits- ■■■■■■■■ price would have covered all of their own overheads, including the cost of running their design department, plus a profit, as normal. Given that much of the V8’s development costs had already been incurred, it must have taken a severe lack of confidence to simply throw the business away.

From a purely design-related standpoint, increasing the capacity and re-tuning the engine’s breathing, to move its torque peak lower down, would have made it a viable alternative to the NTC335. I do not think 13.1 litres was enough to do this, in the early 1970s. Pegaso tried to get 352bhp DIN out of their 12.6 litre six in 1972, and look what happened- cooling problems!

59

[zb]
anorak:

ramone:
So why didn`t someone try to put these improvements into place or do you think it was big brother holding them back?

There probably wasn’t enough meat in the bores to allow a further increase in capacity. That is why I asked Mr. ERF whether he thought it was possible.

The other possible reason is that Leyland realised it had bitten off more than its design capabilities could chew, having made a mess of the V8 and the 500. Even if it could retain some faith in its engineers to make the design competitive, the shopfloor could not, at the time, be trusted to build the things with anything like proper quality control. Buying in the 14 litre ■■■■■■■ would undoubtedly dent Leyland’s profits- ■■■■■■■■ price would have covered all of their own overheads, including the cost of running their design department, plus a profit, as normal. Given that much of the V8’s development costs had already been incurred, it must have taken a severe lack of confidence to simply throw the business away.
In your opinion do you think they could have made it work?

From a purely design-related standpoint, increasing the capacity and re-tuning the engine’s breathing, to move its torque peak lower down, would have made it a viable alternative to the NTC335. I do not think 13.1 litres was enough to do this, in the early 1970s. Pegaso tried to get 352bhp DIN out of their 12.6 litre six in 1972, and look what happened- cooling problems!

In your opinion do you think this engine could have been modified successfully?

60

ramone:
In your opinion do you think this engine could have been modified successfully?

Anything’s possible! They had the crank bearings sorted, according to the bloke that Gingerfold spoke to. Let’s assume that a bigger radiator would have cured the overheating. Earlier mention of running at a fast idle helped to cool an overheating engine suggests a slightly higher flow rate from the water pump would not have gone amiss. There would have been endless combinations of possible modifications. The only big hurdle was the small capacity- 14 litres would have been ideal, so it could sit above the TL12 in the range. Leyland would have preferred to make their own engine, rather than give their own wages to ■■■■■■■■ If there was a deciding factor in the demise of the engine, it was the size of it. The build quality/industrial relations issues affecting Leyland cannot have helped the engine’s cause. It would have been a brave decision to trust a problematic project to those factories.