I'm doing an engine rebuild. I split the case etc, etc. I'm reassembling it. I reinstalled the crankshaft and the camshaft so the marks are aligned. I don't think that it's at TDC with the two gears lined up. If I moved it to TDC, is there any reason why I can't line up the dist. gear?
I'd rather do it now instead of trying to do with the case reassembled.
make sure the timing marks on cam gear and crank gear are lined up...that is the most important thing..then you can rotate it and install the distributor drive gear if you wish...don't forget the two spacers under the distributor drive pinion.
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It isn't. Notice that the keyway in the cam's driver-gear is directly opposite the two dots. When the keyway is at 3 o'clock the #1 cylinder will be at TDC on the compression stroke.
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None at all. In fact, that is the accepted procedure. But you must also provide a distributor and hold-down clamp to hold the distributor gear in position.
Be sure to provide the required end-play for the distributor's pinion gear and see to it that the gear train is properly lubricated. If you don't, the drag of the pinion gear when rotating the crankshaft tends to lift the nose of the crankshaft and you can end up with the #3 & #4 bearings coming off their pins.
Interestingly enough, the main cause for the pinion gear to climb out of position (ie, the need for it to be held down) is improper clearance between the cam gear and the cam's driver gear. VW provided NINE (!) different sizes of cam gear to accommodate the minor variation that is normal between the axis of the crankshaft and the axis of the camshaft. Unfortunately, most after-market cam gears come in just ONE size. If you're lucky it will be too loose but in most cases it's about equal to a +3 size, which is generally too TIGHT for a new, after-market crankcase. If you're not familiar with this aspect of VW engine assembly, you may find my article 'Dialing in Your Cam' of interest. (I've re-posted in my blog but without the photos & drawings that supported the published version.)
-Bob Hoover
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