Balance shaft

[lumpy]

Hi all, I am about to rebuild my V6 series II engine. Can I leave out the balance shaft if I am having the whole engine balanced. Is there any advantage in leaving it out.

 

[jules]

i think you're supposed to check the condition of the shaft bearings at least.

you didn't say what model it was, but they're all pretty much the same in that respect (i assume, i really don't know).

 

[VTSSDUDE]

I would leave the balance shaft in if I were you, it will cause major off balance in the motor.
Those Buick V6s had problems with their balance so might be a good idea to leave it in there.

Cheers,
Jim

 

[AirStrike]

If your getting it done by someone know knows what they are doing I say get it fully balanced and leave it out, and run a double row timing chain.
AirStrike :air:

 

[Garth]

take it out before you get motor ballanced, otherwise you will kill your motor and waste all the money you spent in getting it done.

cheers
garth

 

[VTSSDUDE]

That's interesting, So if you did balance the motor. You wouldn't need the balance shaft?

Cheers,
Jim

 

[jules]

ahh... i misunderstood your post in my first reply.

i don't see how you can leave out the balance shaft. it's not as simple as balancing the rest of the motor.

the balance shaft runs at double (?) engine speed and acts to counter secondary harmonics (i think). it's not the same type of balance as when one piston weighs more than the other, it's more complicated than that.

 

[VTSSDUDE]

Well that's what I thought. Yes I know for a fact that the balance shaft does rev way faster then the motor itself.

Cheers,
Jim

 

[myVRrules]

I think I read recently in one of the popular magazines recently that you can leave it out if you fully balance the motor. I'll try to track the article down so you can get hold of the mag.

Don't know if I can post info from magazines, but if I can find the article again I'll email the date and title to you and you can track down a copy...

 

[sircruisealotVS]

it is possible to leave the balance shaft out, but for a street engine its not a wise idea...the life of the engine will be significantly reduced and the gains are minimal. it's fine for race/track cars not to have one because they spend hardly any time in the lower rev range, and are pulled apart regularly for a freshen up.