CCT Replacement

[pmcq]

Hello All,

Just doing a CCT replacement at the mo... I've all the hard work done. I can see the FT (front) an RT (rear) marks on the flywheel. By lining these up am I ok to pull the old tensioners or do I also need to remove the cam covers and check that the cam marks are facing away from each other?

Have tried searching on on the forum but cant seem to find it!

Cheers
Thicko.

[sirch345]

Hello All,

Just doing a CCT replacement at the mo... I've all the hard work done. I can see the FT (front) an RT (rear) marks on the flywheel. By lining these up am I ok to pull the old tensioners or do I also need to remove the cam covers and check that the cam marks are facing away from each other?

Have tried searching on on the forum but cant seem to find it!

Cheers
Thicko.

Yes you do need to remove the cam covers as the the engine could be 180 degrees out, the cylinder you are working on needs to be on the compression stroke, it needs the cam covers removing so you can check the marks on the cam wheels are lined up with the top of the cylinder head, then the cam lobes will not be opening any of the valves, hence no tension on the CCT's.

HTH,

Chris.

[dookie]

I think the marks can line up with the piston at the top but not on the compression stroke ie: there will be valves open and tension from springs on the cams.
I took of my cam covers when i did mine , im sure in the haines manual it you can have the marks lined up correctly but the engine be 180 degrees out.
Better to be safe than sorry , i know the fronts a bugger but the back ones easy

[dookie]

Typing at the same time then sirch

[Stormin Ben]

Can you not look down the carbs and watch the valves to work out if the cylinder is on compression or not?

Rotate the engine, watch the inlet valves open and then close.
Keep rotating the engine until the marks line up
Hey presto, TDC on the compression stroke

However,
The above suggestion is NOT from experience. I can't actuall remember if you can even see the valves (or stems) by looking through the carbs, it was just a though

[markg]

Speaking from experience here, its worth the time taking the rocker cover off, as long as the cams are not loaded on the cam followers there is no problem. Ideally the piston needs to be TDC on the compression stroke but as long as the cam is not loading the followers all should be ok. If the timing is 180 degrees out the cam followers are still not loaded, they just face away from each other and downwards but no tension is on the cam followers.
While mine was in bits I spent a bit of time experimenting to understand it all. The biggest problem with the haynes manual is that it doesnt explain that taking a tensioner out when one set of valves is open will result in the chain jumping and your timing going out. You want to read the section on refitting the rear barrell camshafts with the front intact if you really want to be confused

[markg]

Yes you can see the exhaust valves with the carbs off but not sure if you can tell if they are open or not.