fresh l20b not starting

[datsunaholic]

When building the engine, there are several things that need to be timed.  Timing the camshaft is doen with the front cover off on initial install- there are marks on both the crank sprocket and cam sprocket, so it's simply a matter of setting the right number of links between the 2 and then ensuring the cam timing it right at TDC.  The crank sprocket keyway points straight up when the crank is at TDC, so that's how you know it's there before the timing cover is installed.  Of course, you can't set the ignition timing with the timing cover off, and you can't see the crank sprocket or keyway once the timing cover (and pulley, washer, and bolt) are on.  Hence the use of the external timing marks, which are there so you can set the ignition timing (but also useful for finding TDC if you have to reset the cam timing once everything is installed).

 

Without the timing marks, setting ignition timing is simply a guessing game.  You can get close, but it's still a guess as to where it's really set.  Still should be able to get it running unless something is really screwed up.

[DAT510]

another method would be pulling crank sprocket and making sure the crank keys are in the 12 O'clock position

[datsunaholic]

Don't even need to pull the sprocket, just the crank pulley.  The keys for both are in the same line.  And really, just need to take the nut and washer off since you can see the keyway at that point.  Can paint a line on the pulley if need be.  Of course, with the L-engine being slightly tilted, and knowing that motor mounts aren't a perfect science, determining true "12 o clock" might be difficult.