Octavia VRS CUPA engine has had the crankshaft removed due to damage, I have sourced a used replacement and am trying to understand how to reassemble it as there are two  gear driven balance shafts. The manual says if balance shafts are fitted then the crankshaft cannot be removed, also I have been told that it is not possible to reassemble as only the factory have the equipment to do this. Has anyone got any experience of this issue? Can I just remove the balance shafts as these appear to be optional for this engine?

Its very odd - the manual for this engine states:

The summary of components refers exclusively to engines without balancing shafts.

 

I cant see anything in the manual about crankshaft replacement - but then again I remember my first VW from 1999 specified never to remove the crankshaft as it would allow the engine block to twist - so theyve said that as long as i can remember. But with balance shafts they have to be timed correctly. 

I’ve a notion the cupa engine doesn’t have balance shafts. Think I read about it when looking at dpf deletes on dark side developments website 

Balance shafts are present on both the CUPA and CUNA 135kw EA288 engines. Crankshaft and balance shafts will be replaceable with the right equipment and knowledge, manual says not however it's likely related to them being installed once and the designers thinking there's no need to replace... Probably easier to get whole 2nd hand crankcase though!

Hi All,

Thanks for the replies. All I can find on the topic is that specialist equipment is needed to ensure the crank and balance shafts are installed with the right timing and amount of backlash in the gears. It looks like I have two options, either take the balance shafts out and rebuild without them or get a 2nd hand unit.

17 hours ago, RussM said:

Hi All,

Thanks for the replies. All I can find on the topic is that specialist equipment is needed to ensure the crank and balance shafts are installed with the right timing and amount of backlash in the gears. It looks like I have two options, either take the balance shafts out and rebuild without them or get a 2nd hand unit.

All I can add is I’ve read a couple of threads on here where people have tried to rebuild these cuna or cupa engines and it has ended badly. One guy never replied again after his rebuild had obviously gone badly wrong.
Therefore, I would go 2nd hand unit.