37 replies to this topic

[Mat Jackson]

It depends on the position of the pistons...
If you move the crank, asking as the uppermost pistons go down you will be fine...
If moving the cams, you risk damaging a valve if one of the pistons is near the top...


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[tommobot]

Surely at any given point at least 1 valve will be lower than others.

How can I rotate both the cams, and crank without risking clash?

[vocky]

set the crank woodruff key to the 3 'O' clock position or 9 'O' clock

[tommobot]

Right, so Woodruff key to 3o'clock..

Check with a dowel or similar through spark plug holes that pistons are level across all 4..

On that basis I should be able to rotate the cams 360 if needed?

The cam sprockets can only fit on 1 place I believe..

Fit sprocket and try and line up the timing marks as best as possible..

Rotate engine with chain fitted to check?

It sounds a recipe for disaster 🙄

How do I ensure the coloured markers line through on the chain as surely if the crank is at 3oclovk it won't line up at all?

Or am I missing something?

[Mat Jackson]

Right, so Woodruff key to 3o'clock..


Check with a dowel or similar through spark plug holes that pistons are level across all 4..


On that basis I should be able to rotate the cams 360 if needed?


The cam sprockets can only fit on 1 place I believe..


Fit sprocket and try and line up the timing marks as best as possible..


Rotate engine with chain fitted to check?


It sounds a recipe for disaster 🙄


How do I ensure the coloured markers line through on the chain as surely if the crank is at 3oclovk it won't line up at all?


Or am I missing something?

Once you’ve got the cams in the right position, rotate the crank to get it to no1 tdc - the dowels will help spot this...

Then fit the chains as the coloured links will then line up with the timing marks


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[tommobot]

Ok.. I think I understand now..

Crank pulley currently at 3 o'clock, ensure pistons are mid stroke.

Fit sprocket and adjust c to have lobes 1 & 4 at 12 o'clock..

Rotate crank to 1 o'clock.. am I ok to turn anti clockwise from 3 o'clock to get to the 12 o'clock position?

Fit cam chain.

[chris_uk]

Rather than rotate the cams, why not just undo all the bridges so the cams are loose, all the valves will be seated home and then turn the crank to tdc then install the cams again in the correct orientation.

Impossible to touch anything that way.

Edited by chris_uk, 29 September 2019 - 01:42 PM.

[vocky]

Ok.. I think I understand now..

Crank pulley currently at 3 o'clock, ensure pistons are mid stroke.

Fit sprocket and adjust c to have lobes 1 & 4 at 12 o'clock..

Rotate crank to 1 o'clock.. am I ok to turn anti clockwise from 3 o'clock to get to the 12 o'clock position?

Fit cam chain.

 

cylinder 4 needs to have the cam lobes sort of pointing towards each other - 10 'O' clock and 2 'O' clock

 

crank pin should then be at 12 'O' clock

 

you will not have any issues with valves touching pistons if you do that

[tommobot]

For absolute clarity, I presume cylinder 1 is closest to timing chain, 4 closest to flywheel?

[vocky]

that is correct, cylinder 4 is next to the gearbox

[vocky]

useful thread - https://z22se.co.uk/...m-chains.10042/

[tommobot]

Ok, I've had a read through vockys linked thread.

 

I've re-fitted the chain loosely, using the ext marker point cable tied to the chain, and lined up the crank and exhaust cam as good as possible.

 

Then re-fitted the intake sprocket aswell.

 

Nothing has moved in the engine since chain wwas removed.

 

Im thinking turn over engine until crank at 12o'clock and then remove / recheck timing on chain?

 

 

 

Thoughts... ?

[Mat Jackson]

This might still be slightly out as the tensioner might pull it a little. Cams can also move slightly when chain is released as the valve springs push on the follows.
However, it will be pretty close and good enough to turn the engine by hand to a position where you can set the timing with the coloured links...


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[Zoobeef]

As above, that will work fine. As long as the plugs are out it'll turn relatively easily so just don't force any undue resistance.

[tommobot]

I'm probably being super paranoid now, but on the balance chain the point between the LHS of the crank pulley and the tensioner, the chain has a tiny tiny bit of slack...

Should this be 100% rigid?

[vocky]

quite normal

[tommobot]

The timing chain tensioner can be inserted fully activated?

Seems to be a right old faff activating with a pry bar, worked first time round but not this time!

[vocky]

I would always install the cam chain tensioner fully activated