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Engine w/ Built-in Clutch

Almost like having two engines
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This Idea is a variation on the theme of starting a car manually, as with an old-fashioned hand crank, or kick-started like a motorcycle.

Suppose we have an N-cylinder auto engine (where N is always at least 2). Inside this engine, at the crankshaft, we insert a clutch between the first cylinder and the rest of the cylinders. The first cylinder connects to the flywheel, and this cylinder alone is attached to the manual-start mechanism --here I'll imagine it to be a pull-cord, like on a lawnmower.

So, you disengage the clutch and manually start what is now in-essence a 1-cylinder engine. Afterward, you engage this special engine-clutch, so now the rest of the engine can be started very easily.

Vernon, Jan 10 2012

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       You'd need to clutch the camshaft as well; otherwise you'd be turning the entire valvetrain. And you need to keep camshaft alignment so it has to be a single-position dog clutch. Where does the ignition timing come from ? On modern vehicles the TDC sensor is usually on the rear flywheel.
8th of 7, Jan 10 2012
  

       [8th of 7], you could probably make always-separate valvetrains work. That would make it more like two separate engines than one "split" engine. Or, perhaps the valvetrains could be entirely eliminated; some modern engines use electric-solenoid-controlled engine valves.
Vernon, Jan 10 2012
  

       // solenoid-controlled engine valves //   

       Ah, what a wonderfully innovative way to improve reliability ...   

       Have you never wondered why civil aircraft piston engines use magnetos, duplicated ignition systems, and carburettors rather than fuel injection ?
8th of 7, Jan 10 2012
  

       N would have to be at least 4, just so that each engine-half could be reasonably balanced.   

       This brings up nightmare images of split crankshafts, separate wet-clutch compartments and seals everywhere. You'd need two oil pumps because now there's a stonking great bell-housing in the middle of the crank shaft.   

       ..why are we doing this again?
Custardguts, Jan 10 2012
  

       marked-for-tagline   

       "The secret of comedic engine explosions"
normzone, Jan 11 2012
  

       //Almost like having two engines//   

       It would be simpler to have a model car engine which could be hand-started and then used to start the main engine or charge the battery. I'm not advocating this, just suggesting that it is simpler than the idea proposed.   

       Some V8s shut off 4 cylinders for efficiency at low power. I don't think rotating all of the shafts and pistons is a problem as long as you don't have to perform all the compression strokes. If you put an entire car on a spit, you wouldn't have a problem turning it with a handle.
marklar, Jan 11 2012
  

       The balance of this engine would be absolutely nightmarish and soon destroy its crankshaft.
RayfordSteele, Jan 11 2012
  
      
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