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Wot No
Water ! |
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| How
the hell do Type 2's work ? Stop that bus, I Movin on up - It's an explosive mixture - the carb and ignition. |
So we know how to stop and steer
but what about moving. Yeah, I guess it's kinda fundamental so lets think about our VW bus's back wheels. The bus has rear wheel drive and with engine above these wheels it gives the Type 2 plenty of grip. The wheels get their oomph from drive shafts which you can see sticking out of the differential, a big word for a few cogs which allow the wheels to travel at different speeds. This is kinda handy when going around corners, as the inside wheel on a curve travels a shorter path than the outside. The Differential also changes the direction of the drive of the engine, to the direction which will spin the wheels round and round, a handy gadget eh... Ever heard of the gearbox ? This is also known as the transmission both apt names for a metal box full of gears which transmits the force of the engine to your wheels. All the gubbins are highly complex but it works on the simple premise that a larger gear turns less when driven by a smaller gear. So on a Type 2 bus the high gear (fourth) makes almost the same number of revolutions going out as it did on the way in. Roughly speaking the wheels are actually turning about one fourth the revolutions of the engine when the transmission is in high. Anyway, all this is because the VW Type 2 engine works best between 2000-3500 revs per minute.All those gears in that metal box increase the ratio between the engine and the rear wheels in lower or first gear and in reverse. In second gear the engine turns about eight times as fast as the wheels and in third about six times.The net result of this is With the engine doing it's thing at about 3500 rpm, the bus will be going a breathless 10 miles per hour in first, about twenty in second, about thirty five in third and a heart racing fifty five in fourth. Wow... the transmission is one cool box of tricks, but it need an arbitrator between itself and the engine. This is called the clutch. Ever seen someone running for a train ? You gotta match your speed to that train and jump just at the right time or forget it. Well the clutch is kinda helping you do that when you change gear, starting or idling so you don't have match everything up and get it going all at once. The clutch consist of the flywheel on one side, and the clutch assembly on the other with the two surfaced clutch plate in between. It all comes together to connect the transmission to the engine and when you hit that old clutch pedal in the cab your compressing springs in the clutch which draw the whole thing apart. Letting you safely change gear. Remember that flywheel I was talking about ? It actually does three things, it acts as part of the clutch, it is engaged by the starter to turn the engine over and it also maintains the revolving inertia of the engine through it's cycles and is bolted to the end of the crankshaft. The crankshaft is fastened to the flywheel and runs in four bearings called the main bearings. These bearings are kinda like the 'main man' nothing works without them. The crankshaft has four cranks and it serves through the connecting rods to change all that up an down motion of the cylinders into the round and round motion of the crankshaft and flywheel assembly. All
that stuff is going on inside the crankcase that is the solid looking |