The usefulness of flywheel dowel pins is often underestimated, they are put back in place without paying attention, with all its consequences. Play at the dowel pins occurs more often than you might think and can only happen in one way: the flywheel is not tightened with the correct clamping force, causing it to loosen and the holes to burst.
Always check the condition of the holes and the flatness of the mounting surfaces (on the crankshaft and flywheel) and never put the dowel pins back into the damaged holes. If the holes are slightly bored, you can repair them by using oversized dowel pins, these oversized pins are also longer.
For engines with higher power, it is advisable to equip the crankshaft with 8 pins, all crankshafts with counterweights are already equipped with them, as well as the lighter flywheels. The dowel pins are available in three versions, in a standard size, an extra long size and an oversized size, the latter also being longer.
The standard size replaces the original pins, the extra long pins are for a better fastening and are recommended for crankshafts with 8 pins or to improve the original 4 pins. The oversized ones are for repairing slightly damaged holes and are recommended to mount the flywheel and crankshaft directly with 8 pins.
To drill four additional holes, you need the right tool, the drilling jig (if necessary mentioned in the options tab) is indispensable, it allows you to drill symmetrical and asymmetrical holes.
Attention: If the overhaul was carried out by Volkswagen at the time, the crankshaft and steering wheel were machined, so shorter dowel pins had to be fitted, 12.5 mm instead of the usual 14 mm. You may have such an engine, in which case always measure the length before mounting and, if necessary, shorten the pins or drill the holes a little deeper.
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