Cam chain model and relpacement.

[max]

Hi Dave, to make this a bit more interesting i found some pictures from when i reshimmed my valves;

As you can see the timing chain tensioner does not alter the length of chain between the sprockets, nothing needs to be done there unless it is one tooth off.

timing for top dead center on crankshaft indicator;






So this is how i lined up the camshafts, i also marked the sprockets on the shaft before separating them so they could be positively identified;


Cams can be out by a fair bit, even a tooth out could still work i am guessing but that is a bit extreme.
At 11:30 in the video Bernie moves the " cam phaser " of the variable valve timing system by some 20 degrees whilst the engine is running by energizing the solinoid with his diagnostic tool, you can see the timing of the red trace moving to the left with respect to the other traces thereby advancing the one cam shaft with respect to the other shafts;




And here is how the cam chain tensioner works;




Seems to me he winds the pusher in by about 10 half turns of the screw driver which gives you an idea how much slack can be taken up during the cam chain's life span.

This tensioner pushes against a plastic cam chain guide over which the chain glides in the non loaded part of the run ( the slack part ) of the cam chain and is also assisted by the oil pressure inside the chain tensioner housing ( don't put the tensioner in upside down, you will block the oil supply to the tensioner housing making the chain running loose )