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without timing belt?

Dear all readers and mechanics,
<br/> I'm more familiar with diesel engine on trucks like Detroit, Cummins and Caterpillar than cars. I'm wondering is it possible diesel engine runs on gear driven without timing belt or chain be found in any cars? I mean any gas engine cars? I would like to know
<br/> Thanks
<br/> Pete


  • edited March 2009
    Are you asking has anyone made a Diesel engine with a gear driven camshaft? For large truck or private car/truck application? I have seen gear driven injection pumps.
  • edited March 2009
    What I am trying to say is yes it is gear driven camshaft goes with gear driven crankshaft other gears all together fully gear driven without belt or chain but on gas engine? and gear driven injection pumps no longer in trucks it is fully ECM control. Do you know what I am trying to say?
  • edited March 2009
    2.5 chevy 4cyl eng had no chain or belt it had gear driven cam.
  • edited March 2009
    Maybe if you say what you are trying to do I will get it. Are you making a engine swap or just doing some reasearch or is this a "bet" type question. Like "I bet they made this that way".
  • edited March 2009
    I remember some Volvo engines in the early 70s which had only a gear-to-gear arrangement to drive the camshaft. There was no timing chain or belt.
  • edited March 2009
    Summit Racing sells kits to give any small block Chevy a set of gears rather than a belt. They are rather noisy though.
  • edited March 2009
    I think you are asking, "Are there any gasoline engines which don't have timing chains or timing belts, similar to diesel engines not have timing belts/chains?"
    As far as I know, in today's cars, all four-stroke gasoline engines have timing chains/belts, or gears which perform the same function. Two-stroke gasoline engines may be what you are thinking about. Maybe, a hundred years ago there may have been four-stroke gasoline engines with a different design; but, I'm not an automotive historian.
    On the two-stroke engine, the piston itself acts as the intake and exhaust this little video shows:
  • edited March 2009
    The old Chevy 250 straight 6 used a gear driven cam.
  • edited March 2009
    Overhead cam engines all use either a timing belt or a timing chain. They are all overhead valve. Overhead valves may either be driven by an overhead cam (see above) or by a gear-driven cam + push rods + rockers. Side valve (flathead, L-head, etc.) designs have a gear-driven cam + push rods (usually) + the valves themselves. Two cycle engines generally have no valves (except a reed valve to keep fuel/oil/air mix from blowing back through the carburetor). Various other designs have been built, including sleeve valves. Diesel (compression ignition) and Otto cycle (spark ignition) can have any of these valve configurations.
  • edited March 2009
    80 or 81 Olds Starfire had a timing gear.
This discussion has been closed.