Lots of confusing information there.

Very briefly, the 2.0 PD differs from the 1.9 in having twin Lanchester balancing shafts which contra-rotate at 2x crank speed. The first engines used a chain drive which was a complete disaster (pictures on your link) and the later engines a gear drive. All 2.0 PD Superbs got the geared drive.

The problem with the Superb's 2.0 PD engine is the drive from the slave balancer shaft to the oil pump, which is a piece of 6 AF hex bar which has inadequate engagement depth with the grooves in the slave shaft. Due to the extreme torsional oscillations in the drive (the same ones which wrecked the earlier chain drive system) the grooves in the balancer slave shaft and the corners of the drive shaft strip and drive to the pump is lost.

Apart from offloading a pile of duff engines into "Skodas", VAG have not done much, as far as I can see to properly fix this - the oil pump drive shaft length increased from 75 to 100 mm according to EKTA, no doubt as a cheap fix by increasing the engagement length. They're never going to fix it properly either, the PD engine is dead.

Avoid all 2.0 PD engines. The 140 in practice produces no more power in the useful rev range than does the 1.9/130

The 1.9 engine has a chain drive to the oil pump - only. It's a nice smooth drive with no torsionals, just what a chain needs. The drive on the 1.9 will last the life of the engine.

rotodiesel.

Hi Roto i wondered is it possible to replace the faulty 2.0 tdi engine with the good engine with no inherent problems or would that **** everything up ?

Reassuring to note that there is a definite improvement in quality of the replacement balancer units. Is there a part # for these or a related service Is it possible that this part was also used on later Mk1 Superbs, or is it likely that there was a shed somewhere that VAG kept the shabby units and said to Skoda "Here, have those and stop annoying us". Considering a pre-emptive strike and getting local garage to do for a TB change and BSM replacement before anything unpleasant happens (it is 4 years old and just squeezed off 30K on the clock). Is this similar to the "chainless" upgrade that our friends over the water have been doing on their BHW engines (part 03G 103 295Q I think!).

The latest modification       to the oil pump balancer shaft came in ,in 2011 cost around £1,000 plus fitting