Death to you, Camshaft sprockets.

[Acheron]

Trying to remove the head on a 2000 Vectra, with the z22se engine.

Everything is pretty much all done, with the exception of removing the sprockets from the cam, so i can slide the head up and over. You cant lift the head up as the sprocket bolt is in the way.

I simply cannot under no amount of force, remove the sprocket bolt. This isnt a picture of my engine, but its the bolt in the middle of the sprocket, and its jammed fast on both sprockets.



Without them coming off, the whole job is stopped. I snapped one ratchet already, dented a spanner and slightly rounded the head of one of the bolts (but a spanner and socket will still grip, i stopped before i rounded any more).

Ive hit it, kicked it, smacked it with a hammer, leaned on it, pushed it, pulled it... done everything but eaten it.

Any suggestions how i could get these two bds off?

[IforB]

Heat?

[Mr Will]

Are they left-handed threads?

[Rotary Madness]

Fire, lots and lots of fire.

[ollie854]

Have you tried heating it up?

[AnotherClarkey]

Mr Will said:

Are they left-handed threads?

And if they are they are now on really fking tight!

[Acheron]

Mr Will said:

Are they left-handed threads?

Haha, this was my other severe concern. I *think* they are set up to come off on anti-clockwise rotation, and this was the belief i got from a family member who works at a garage.

If anyone else has worked on the z22se, maybe they could verify it.

In terms of heat, what is the best way of doing it?

[Dangerous2]

bonfire, blowtorch, candle, deodorant can and lighter, radiator, bbq, nuclear bomb, magnifying glass and sunny day.

[Mr Will]

Which way does the sprocket rotate when the engine is running?

[Jimmyarm]

Tried an impact gun ?

[voicey]

Jimmyarm said:

Tried an impact gun ?

This. I have a mains powered impact gun from screwfix - cost £40 or so. It'll undo anything.

[Acheron]

Mr Will said:

Which way does the sprocket rotate when the engine is running?

Forward, towards the front of the car. It rotates clockwise when looking from the right hand side (as in the picture). At least, this is the way i have rotated it to get #1 at TDC, i assume it will only rotate one way when the chain is attached.

[eldar]

Acheron said:

Mr Will said:

Which way does the sprocket rotate when the engine is running?

Forward, towards the front of the car. It rotates clockwise when looking from the right hand side (as in the picture). At least, this is the way i have rotated it to get #1 at TDC, i assume it will only rotate one way when the chain is attached.

I'd suspect LH thread.Try tightening it.

[useyourdellusion]

If it rotates forwards (clockwise), it will be a reverse thread then I would imagine....

[Toyless]

Mr Will said:

Are they left-handed threads?

This.

[Acheron]

Either way, i tried them both ways and they wouldnt move.

[attym3]

Another 'left handed thread' here.

Mark

[heebeegeetee]

Hi, i've just checked Autodata for you, and it's not giving a warning that the cam sprocket bolts are left hand threads. I would expect it to if they were.

It does stress that the sprocket bolts MUST only be used once, (and its 85nm + 30degs + 15 degs to tighten) but no mention is made of them being left hand threads.

I'd urge you to try to find out for sure, 'cos you'll be in right doo-doo if you round off or shear a bolt.

[jbi]

try heat and wax

http://www.youtube.com/watch?v=KwKHSvKfnHI

[mcford]

A work colleague recently replaced the timing chains on one of these engines, I'm fairly sure that he removed the cam shaft sprockets to do this. as I recall they were a standard right hand thread and there is a flat on the cam shaft to enable a spanner to be put on it to oppose the force required to loosen the bolt.

He did not have to resort to heat or impact tools to do it.