V8 Engine Vibration

[VL dude]

Hi. New to the forums, and this is my first post.
I have a factory 304 VL which has developed a vibration between 2500 and 3000rpm.
The problem is present when the vehicle is stationary and in park or neutral, as well as on the road so I have eliminated the gearbox (auto), tailshaft, diff, wheels, suspension, steering.
I have replaced engine and transmission mounts, harmonic balancer, dizzy cap, plugs and leads.
I am not an expert by any means and have never pulled an engine apart, however I am starting to think it to be internal to the engine somewhere.
Can anyone suggest what I should be looking for and how I might test to eliminate possibilities before I pull this thing apart? I am on a very limited budget as a single dad so cant just spend money for the sake of it.
Thanks

 

[Smitty]

.. what sort of vibration?

a buzzy one ? (like something from the valvetrain) or rocking type one? (yes.. like a failed engine mount)
or one from a miss?

 

[VL dude]

.. what sort of vibration?

a buzzy one ? (like something from the valvetrain) or rocking type one? (yes.. like a failed engine mount)
or one from a miss?

Not really sure what you mean... however its like a high frequency resonating humming/buzzy type one. If I had to verbalise it I would say it is like a repetitive VRR VRR VRR vibration. The resonating aspect of it is as annoying as the actual vibration through the car.

 

[rambunctious]

Had the same problem with 5 litre VL, harmonic vibration as you describe, cost me a bloody fortune after the dick head mechanic fitted a replacement engine and used Repco engine mounts.
Actually he used nolathene first up and the car nearly shook itself to death, then Repco mounts, not as bad, but not acceptable just the same as the vibration nearly did your head in.
I changed to genuine engine mounts from Zupps and the vibration went away.
Not genuine from Repco or any of the others, but genuine from Zupps, they are a special compound.
I did the gearbox mount from Zupps as well.

 

[VL dude]

Thanks. Ordered replacement engine mounts from Holden dealer. Installed and made no difference.

 

[strgas]

remove each drive belt one by one and retry the engine at revs see it this makes a difference after removing each belt

 

[Waughy]

Is the exhaust secure? I had a 5L VL Calais years ago (wish I'd kept it) and didn't have any issues like you are. Just trying to think what else it could be before pointing at the engine (internally). Another VL I owned had an annoying buzz at certain revs, don't recall any vibtration, but it ended up being the muffler. Internally it had corroded and disintegrated, the bussing was the remains bouncing around.

 

[Lacksballs]

I've got the same VL 304 V8 in my VK Gp C & when I first got it going it had a noise from the front of the engine, just used a trusty long square shank screwdriver (handle on the ear trick) on the all the front drive consumables & ended up being the AC clutch bearing, changed out the idler bearing at the same time. If you don't know what you're doing DONT put a screw driver anywhere anything rotating! It will hurt if it all goes wrong, maybe try "strgas" method.

 

[David Morgan]

Hey guys just came across this post...I have a VL 5.0 same vibration between 2200-3500 it had the vibration when the motor was stock and still has the vibration since it's been pulled down and machined and stroked and that's with new harmonic balancer, mounts engine and box....so I don't know what the hell is going on with it maybe loosen all the mounts and take it for a spin...let everything settle in
Hope this helps