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The engine in the peugeot 407 1.6hdi sw which I am using in Germany has now 120k km and is the best part of the car.when you look at these second hand some have really star ship mileages - its not uncommon to see a Mercedes taxi that has gone round the clock.
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Erm.......are MB now reduced to using PsA engines
Sigh
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The D4D engines in Toyotas are excellent for reliability, and the diesels in Nissan/Renault seem to be quite good too from what I have heard. My favourite though is the engine in the S320 CDI. A mate has a 07 model with 150k now and still going strong like the day he bought it,no problems except wear and tear items. The Jtdm engine is my Alfa has been great so far too. I have only ever heard good things about the Korean diesel engines too, especially the 2.2 in the Sante Fe.
MB has had lots of injector problems on Blue Efficiency engines. Now sorted I think..
Yaris D4d engines appear v reliable: the Yaris forums get very few issues: mainly choked up EGR valves due to lots of town driving or cheap nasty diesel..
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I had a Auris van D4D over the winter last year and it was excellent,it was the 1.4 engine and was great,started first time everytime!
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Certainly looks like a japanese car is the way to go here. It's quite, striking, however, the difference in fuel economy between EU and Japanese diesels. I often wonder whether the Japanese cars are so reliable because they don't push the same boundaries as the EU cars.
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Its not just the engine its how its plumbed-in to the car that decides whether the installation will be a success or a failure. In particular if the engine is taller than the radiator and if the owners manual indicates a complicated bleeding ritual, disaster is virtually assured. Avoid like the plague any car that has bleeder screws in its radiator hoses. Avoid any car with a cooling system that needs to be vacuum bled. I can only assume that some car factories employ young dudes who are straight out of Uni and lack real world experience. In particular they do not understand that metals and gaskets are often microporous. If an engine leaks 1cc of gas per hour into a well-designed cooling system it will not be a problem as the gas will vent-off from the radiator header tank. On the bad designs air locks and overheating will occur so its a case of caveat emptor. Perkins make excellent diesel engines but most of these are far too large for passenger cars. It is a good idea to have an oil cooler that does not rely on the radiator as combined cooling puts all ones eggs in one basket. Especially be aware of where the water pump is. I'm a senoir citizen now but over the years I have noticed that engines that have high mounted water pumps are usually very troublesome indeed. The laws of libel probably prevent me from trotting out a long list of bum designs so you will have to work it out for yourself. Note that some "clever" car designs now have water cooled transmissions. One star design has oil pipes in the radiator which corrode. Once this happens hot water surges into the transmission which then explodes and spews its gears over the road. Well what can you expect for £57,000 ? (and its now done it twice!) Good luck!
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With diesels the more you use them the more reliable they get. My dad did 30,000 a year for 25 years in every type of Fiesta diesel from Endura to TDCi, doing over 100k in each one and never had a failure.
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With diesels the more you use them the more reliable they get. My dad did 30,000 a year for 25 years in every type of Fiesta diesel from Endura to TDCi, doing over 100k in each one and never had a failure.
Very true, diesels that get pottered around town at little more than tickover are the troublesome ones. I have done about 150K miles in 3 different diesel cars with none of the usual engine issues at all.
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Its not just the engine its how its plumbed-in to the car that decides whether the installation will be a success or a failure...
Interesting post, cheers!
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"Well what can you expect for £57,000 ? (and its now done it twice!) Good luck!"
Certyainly not reliable MB engineering.
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It seems strange but I've never owned an unreliable car, let alone a diesel. Maybe it's because I can't/won't pay for garages to look after them and so I do look after them or is it because I don't do lots of miles in my cars. My cars usually have in excess of 110K on the clock when I buy them.
I drove a 1.7 D Astra van to 197K and it had a very hard life. Previous vans reached over 150K with dealer servicing before the lease ended. Only 2 went bang (I wasn't driving them at the time) both hadn't had their timing belts changed due to dealer incompetence. This is when the service interval was 4.5K for oil and filters and 9K for main servicing.
Steve.
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I have heard nothing but bad things about the honda 2.2 diesel, look it up.
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You have to put the VAG 1.9 PD up there with most reliable engines.
Like all 2 valve diesels it avoids the troublesome swirl flaps.
The unit injector set up is also a bonus. Unlike electronic rotary distributer pumps, you don't have a problem with pump timing when the belt is changed.
Unlike common rail, there are no lubrication issues with a high pressure fuel pump.
Unlike the more 'advanced' 2.0 16V engine, there isn't a stupid Lanchester shaft set up either. Utterly pointless on a diesel engine anyway.
Surprisingly, given the limited window of injection timing, the PD engine seems to cope with DPF pretty well.
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Have to agree that the 1.9PD was just about the pinnacle of diesel engine efficiency, reliability & relative simplicity. The 1.9 was never fitted with DPF, so what with the ballance shaft/ oil pump drive issues with the 2l, it is best avoided altogether.The CR 2l also seems to have no issues & is at least 10% more efficient than the PD on a run although is a far more complex unit, but with better diagnostics.
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Mk V Golfs and Skoda Octavias were definitely fitted with 105hp 1.9equipped with DPF!.
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Another vote here for the 1.9 VAG PD engine. This unit has probably the highest thermal effeciency of any diesel engine ever produced in this size.
Picking up a few points above, the DPF system as applied to the PDs was a bodge - simply because there is little pressurised fuel available for soot-burn injection when the engine exhaust valves are open, as is required for regeneration. The unit injector cam geometry is, quite rightly optimised to give very high pressure fuel delivery at the time the engine needs it to do useful work. I would not recommend a PD engine equipped with a DPF to anyone.
The VAG-specific (as opposed to the generic) diagnostic system on the PD engines is extremely comprehensive. It allows for instance, the measurement of individual injector fuellings at idle in order to assess balance. The control software is similarly well specified - engine acceleration is measured between sucessive injections and the fuelling is corrected to allow unbalanced injectors to give even running.
Contrast this with the Ford system which requires the control ECU to be calibrated with the delivery characteristics of the fitted injectors. There is no facility to compensate for wear and the coding seems to get "lost" on occasions.
There's nothing wrong with Lanchester balancer shafts - it's just that VAG seemed to be incapable of designing a durable drive for the shafts and the oil pump. I suspect the apprentice did the job whilst the more experienced engineers were working on the CR engines. A seasoned engineer would never attempt to drive balance shafts with a chain due to the diffculties of torsional oscillation and resonances.
Although undeniably smoother and (a few HP fuel pump failures aside) largely reliable, the VAG CR engine does not in practice match the efficiency of the pre-DPF PD. With similar injection pressures, a soot-filter restricted exhaust and worthless fuel injection for soot burn off, there's no reason why it should. I suspect a little numerical massaging...
659.
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I have had my Toyota AURIS 2.0 Diesel D4D for 3 years, now 5 years old. NOTHING has gone wrong. Not the best diesel engine but a very good one. Cruises very nicely at high (illegal) motorway speeds in 6th. Will doddle in town at ~1,000 rpm in 4th.
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Another vote here for the 1.9 VAG PD engine. This unit has probably the highest thermal effeciency of any diesel engine ever produced in this size.
Picking up a few points above, the DPF system as applied to the PDs was a bodge - simply because there is little pressurised fuel available for soot-burn injection when the engine exhaust valves are open, as is required for regeneration. The unit injector cam geometry is, quite rightly optimised to give very high pressure fuel delivery at the time the engine needs it to do useful work. I would not recommend a PD engine equipped with a DPF to anyone.
The VAG-specific (as opposed to the generic) diagnostic system on the PD engines is extremely comprehensive. It allows for instance, the measurement of individual injector fuellings at idle in order to assess balance. The control software is similarly well specified - engine acceleration is measured between sucessive injections and the fuelling is corrected to allow unbalanced injectors to give even running.
Contrast this with the Ford system which requires the control ECU to be calibrated with the delivery characteristics of the fitted injectors. There is no facility to compensate for wear and the coding seems to get "lost" on occasions.
There's nothing wrong with Lanchester balancer shafts - it's just that VAG seemed to be incapable of designing a durable drive for the shafts and the oil pump. I suspect the apprentice did the job whilst the more experienced engineers were working on the CR engines. A seasoned engineer would never attempt to drive balance shafts with a chain due to the diffculties of torsional oscillation and resonances.
Although undeniably smoother and (a few HP fuel pump failures aside) largely reliable, the VAG CR engine does not in practice match the efficiency of the pre-DPF PD. With similar injection pressures, a soot-filter restricted exhaust and worthless fuel injection for soot burn off, there's no reason why it should. I suspect a little numerical massaging...
659.
I have to take issue with you on the point that you make " A seasoned engineer would never attempt to drive balance shafts with a chain due to the diffculties of torsional oscillation and resonances."
On the contrary, Honda UK employ a great many seasoned engineers and the balance shaft/oil pump assembly on the 2.2 CDTI Honda is chain driven from the front of the crankshaft. The two balance shafts are geared together 1:1 and driven at 2:1 from the crankshaft by a chain along with the oil pump.
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However you drive them, I still don't see the point of Lanchester shafts on a diesel engine. They make a significant contribution to the NVH of a petrol engine, but the effect is much less pronounced on a diesel. The friction and extra cost of Lanchester shafts is probably not much less than an extra cylinder which would would be far more effective in terms of NVh at low speed, not to mention the extra low rPM torque.
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I bought an older VW 1.9 PD-engined car (Seat Leon Mk1), wanting to avoid DPFs on later diesels, and the engine's been mostly fine but the rest of the car's developed loads of faults and I've spent over £2.5k getting it sorted, wiping out years of fuel savings, so beware of thinking as I did!
I find the VW diesel a bit unresponsive from low revs compared to the Focus 1.8TDCI I had before, but it's the PD150 and some say the 130hp version is more responsive.
I can't argue with efficiency, though, having averaged 55-56mpg on two recent trips from Aberdeen to North Yorks and Northumberland - mix of motorways and 'B'-roads - with the engine being remapped to 175hp / 300lbft.
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"However you drive them, I still don't see the point of Lanchester shafts on a diesel engine"
I think they are brilliant, reduces NVH a treat, both our diesel vehicles have them, a Honda Civic FN3 Civic 2.2 CDTI and an old dog of a L200 pickup with a 4D56T 2.5 litre IDI motor.
Wouldn't be without them-any questions?
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Wouldn't be without them-any questions?
Yes-how do attribute the smoothness to balance shafts? They work in petrols because the inertial forces of the reciprocating assembly is often greater than the force due to the gas pressure, so (partially) cancelling out the second order imbalance is worthwhile. In diesel engines, the gas forces always dominate, so alleviating the imbalance doesn't really achieve much. The smoothness is more likely due to the DMF (Recoil in horror!) and good engine mounts.
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Wouldn't be without them-any questions?
Yes-how do attribute the smoothness to balance shafts? They work in petrols because the inertial forces of the reciprocating assembly is often greater than the force due to the gas pressure, so (partially) cancelling out the second order imbalance is worthwhile. In diesel engines, the gas forces always dominate, so alleviating the imbalance doesn't really achieve much. The smoothness is more likely due to the DMF (Recoil in horror!) and good engine mounts.
As is well known, the unbalanced second order forces can be balanced by two balance shafts rotating in opposite directions at twice crankshaft speed each carrying an unbalanced weight symetrically located from front to back of the engine. The horizontal components of their unbalanced reaction will cancel, but the vertical components will add, phased to cancel out the second order forces.
Having dealt with the theory, the reality is that the Honda 2.2 CDTI doesn't really sound or feel like a diesel and has very little if any movement on it's mounts except when starting or stopping. The 4D56T in the L200 is a big old fashioned IDI four banger of a diesel and for an engine of that size and age is tolerably smooth.
Years ago a Danish company called Bukh built a twin cylinder marine diesel of about 1100 cc and about 20 hp, both pistons up and down together, normally a big twin like this is a real teeth rattler and destroyer of engine mounts, but they equipped this engine with balance shafts,it was renowned as a really smooth engine, so they do work on diesels.
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having dealt with the theory, the reality is that the Honda 2.2 CDTI doesn't really sound or feel like a diesel and has very little if any movement on it's mounts except when starting or stopping.
This has nothing to with engine balance and is entirely due to multiple injection strategy limiting cylinder pressure rise and torque flux.
We see the same nonsense with journalists fawning over the 'perfect balance' of the flat four. In reality the flar four runs rough as a cob compared to the inline four at normally encountered engine speeds. The major source of NVH in a four cylinder engine is crankshaft torque flux. The vertical oscillating motion of the crank (and engine block) is usually fairly minor and easily absorbed by rubber mounts. The imbalance of the inline 4 actually reduces NVH. This is is because the inertial forces on the piston are out of phase with the gas forces and so the dominating torque flux is attenuated by the inertia of the reciprocating assembly. Only when inertial forces are greater than the forces due to gas pressure does the second order imbalance become a problem. This occurs frequently in petrol engines but almost never occurs in diesel engines.
I have run various mathematical of cranshaft assemblies models and all varients demonstrate this behaviour.
built a twin cylinder marine diesel of about 1100 cc and about 20 hp, both pistons up and down together, normally a big twin like this is a real teeth rattler and destroyer of engine mounts.
...which proves my point! If engine balance was such a big problem, Bukh (and all other engine manufacturers) would build 180 degree twins, not 360 degree twins. The 180 degree twin has better mechanical balance than a 360 degree twin. The 360 degree twin is favoured because the even firing interval (cylinder gas pressures) dominate over mechanical engine balance.
The 4D56T in the L200 is a big old fashioned IDI four banger of a diesel
2.5 litres is not large for a diesel 4 pot. Both JCB and Cummins build 4.0+ litre 4 pots-neither bother with balance shafts. Interestingly, Detroit Diesel did use a (single) balance shaft on their 4 cylinder 2 stroke engines. Unlike the Lanchester carbuncle, the balancing shaft was integrated into the camshaft. I'll let you to figure out why only one was required.
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My Hyundai R-series has a single balancer shaft - while it's certainly noisier than any petrol I've driven it doesn't have any issues with vibration or harshness - it's too new to assess it's reliability but being designed/built in-house it should be better than the VM designs that Hyundai used to use.
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having dealt with the theory, the reality is that the Honda 2.2 CDTI doesn't really sound or feel like a diesel and has very little if any movement on it's mounts except when starting or stopping.
This has nothing to with engine balance and is entirely due to multiple injection strategy limiting cylinder pressure rise and torque flux.
We see the same nonsense with journalists fawning over the 'perfect balance' of the flat four. In reality the flar four runs rough as a cob compared to the inline four at normally encountered engine speeds. The major source of NVH in a four cylinder engine is crankshaft torque flux. The vertical oscillating motion of the crank (and engine block) is usually fairly minor and easily absorbed by rubber mounts. The imbalance of the inline 4 actually reduces NVH. This is is because the inertial forces on the piston are out of phase with the gas forces and so the dominating torque flux is attenuated by the inertia of the reciprocating assembly. Only when inertial forces are greater than the forces due to gas pressure does the second order imbalance become a problem. This occurs frequently in petrol engines but almost never occurs in diesel engines.
I have run various mathematical of cranshaft assemblies models and all varients demonstrate this behaviour.
built a twin cylinder marine diesel of about 1100 cc and about 20 hp, both pistons up and down together, normally a big twin like this is a real teeth rattler and destroyer of engine mounts.
...which proves my point! If engine balance was such a big problem, Bukh (and all other engine manufacturers) would build 180 degree twins, not 360 degree twins. The 180 degree twin has better mechanical balance than a 360 degree twin. The 360 degree twin is favoured because the even firing interval (cylinder gas pressures) dominate over mechanical engine balance.
The 4D56T in the L200 is a big old fashioned IDI four banger of a diesel
2.5 litres is not large for a diesel 4 pot. Both JCB and Cummins build 4.0+ litre 4 pots-neither bother with balance shafts. Interestingly, Detroit Diesel did use a (single) balance shaft on their 4 cylinder 2 stroke engines. Unlike the Lanchester carbuncle, the balancing shaft was integrated into the camshaft. I'll let you to figure out why only one was required.
Yes I know that lots of manufacturers such as JCB, Cummins, Gardner, Lister, Volvo, International Harvestor, Perkins etc have made large capacity 4 cylinder motors without balance shafts, but they don't install them in cars do they-why? Because they vibrate too much. The excellent Perkins 4-236 for example is a four cylinder DI diesel of nearly 4 litre capacity (3867 cc) but you wouldn't want to sit behind it for long in a car-even though it was sometimes used to re-engine Land Rovers.
I like my balance shafts-you haven't convinced me to go unbalanced Unthrottled!
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I like my balance shafts-you haven't convinced me to go unbalanced Unthrottled!
Whereas I prefer to be unbalanced!
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HJ speaks well of the Renault 1.6 DCI as the most modern small diesel.
Great posts above, but, apart from buying Japanese / Asian, I'm not sure the discussion's conclusive.
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I think the original poster was asking about current diesel engines, the best of the new bunch is without a doubt the 2.0 tdi vag lump not to be confused with the pre 2008 abortion of an engine produced by vag. The same unit is placed in every model of car, van or 4x4 that vag produce with a 2.0 tdi engine,mechanically the engine is the same in everything only injectors and manifolds change for different fitments.
This engine is closely followed by toyota and mercedes both cannot claim no1 as both are not used in anywhere near the volumes that the vag unit is. Currently we have only replaced 2 of these type of engines and both were changed through crash damage
regards
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I think the original poster was asking about current diesel engines, the best of the new bunch is without a doubt the 2.0 tdi vag lump not to be confused with the pre 2008 abortion of an engine produced by vag. The same unit is placed in every model of car, van or 4x4 that vag produce with a 2.0 tdi engine,mechanically the engine is the same in everything only injectors and manifolds change for different fitments.
This engine is closely followed by toyota and mercedes both cannot claim no1 as both are not used in anywhere near the volumes that the vag unit is. Currently we have only replaced 2 of these type of engines and both were changed through crash damage
As you're excluding the pre-2008 engine, you're referring to a very recent engine that's no more than 4 years old so very few will have done high mileages - no-one would expect any failures in that time !!
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sorry I dont agree, hit the classifieds lots and lots of these engines have in excess of 200k miles on them. We have changed many bmw diesel engines of the same age
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