[southjersey636]

Does the crankshaft on 03-04 636's have a timing mark on them that is not visible unless you take the engine apart because my crank moved a hair past 1-4 top dead center while doing a valve adjustment. I myself believe that the bottom crank sprocket does not have a timing mark other then the 1-4 2-3 that you see when you take the cover off, the main timing is your intake-exhaust cams? anyone familiar with the timing on these engines.

Is it possible for the bottom crank to jump a tooth and mess the whole timing up? Once again Im pretty sure the top exhaust-intake cam timing is the main thing here and the bottom sprocket is only a problem if the cam chain was not even on it.

 

[markketo]

As it's an interference engine, I believe the pistons and valves will collide if either of them is out of timing. You can check it by turning the engine by hand, from the ignition wheel.

You are asking about if the chain at the crank could jump? Very unlikely but if it does so during maintenance, it's no problem. Whlist the cranksaft mark is on 1-4 and cams marks are level with cylinder head, the timing is ok. By removing the tensioner, you can move the chain on cams.

 

[southjersey636]

You are the man lol, I was afraid that the bottom crank might have a timing mark on it behind the case that normally wouldnt go out of timing unless it jumped a tooth somehow, I was getting scared for a minute yesterday when I started doing the rest of the job.