Holden VR v6 - vacumm testing for unsmooth idle

[Pete30nz]

Does this tell us any thing?

[Gareth]

The inlet gaskets are toast

[Charlescrown]

I think Gareth is on the money with that one. I never did undersand the connection with the cooling system was but have come accross it many times now. Looks like you may have finally found the vacuum leak.

[Pete30nz]

Thanks men, I plan to do them. If purchased the mace ones. But only learnt of the aluminium ones yesterday.

Cheers

[Pete30nz]

Tonight effort got me to this stage

[Gareth]

To delete the balance shaft you need to drill and tap the oil galleries, best done to a bare block so the galleries can be cleaned afterwards.

Not really any benefit to a stock/street motor.

[Pete30nz]

Thanks for the reply. I'm sure I'm getting some balance shaft bearing noise. Wondering whether to just take it out. This is the buick 3800, apparently this doesn't have the oil port for blocking?

Cheers

[Charlescrown]

I would think that at each end of the balance shaft would be a pressure fed bearing that would need bocking. From my experience with deleting balance shafts I would never do it again without a complete engine balance.

[Gampy]

I would think that at each end of the balance shaft would be a pressure fed bearing that would need bocking. From my experience with deleting balance shafts I would never do it again without a complete engine balance.

IMO that should be the only time ...

-Enjoy

[immortality]

Thanks for the reply. I'm sure I'm getting some balance shaft bearing noise. Wondering whether to just take it out. This is the buick 3800, apparently this doesn't have the oil port for blocking?

Cheers

This is correct, Only the ecotecs (L36) had the pressure fed rear bearing.

One of the big issues with the V6 motors is the POS harmonic balancers fitted from the factory. For a harmonic balancer/dampener to work it needs to have mass which the OEM balancer is sorely lacking which is shit because these 90° V6 motors have some interesting vibrations/harmonics.

I deleted the balance shaft on my VN s1 engine, arguably the roughest of the V6 motors ever fitted to a Commodore, I added a Powerbond race spec balancer, double row timing chain and fitted new trans and engine mounts and it was the smoothest the engine ever ran.

You can disable the balance shaft just by removing the drive sprocket but you need to leave the sprocket behind the timing chain in place or the chain alignment will be off unless you fit a double row timing chain. Considering it's age the timing chain/tensioner is probably worn out too.

Opening up old engines is a can of worms....