> The book says to turn the engine until
> the valves of any
> cylinder are at the "point of rock" Now in my way of thinking, is
> this the
> same as "balanced"?
Yeah, same thing.
> If I am at No 1 cyl TDC ( i.e. timing marks
> lined up at
> the point on the timing cover), is No1 cyl at "point of rock" ?
Not necessarily. It would be at "point of rock" every other revolution.
Basically, "point of rock" is the TDC between intake and exhaust stroke (aka
valve overlap period, when both valves are open slightly). Remember this is
a 4-stroke engine, it takes two full rotations of the crankshaft for a
cylinder to complete a firing sequence. As my HS Physics teacher put it :
Suck, squeeze, pop, fooey.
> And to take it
> further, should I now be able to slide a ..010 feeler through the
> top of both
> inlet and exhaust valves?
No, the cylinder at "point of rock" will have both valves open slightly, so
you cannot slide a feeler gauge in at all. However, the cylinder that is
opposite (180 degrees away) in the firing order will be at TDC between
compression and power strokes, and so you can check it's valve clearances.
Best to do this in order (although it doesn't matter where you start in the
list, or whether you go forwards or backwards) :
on rock adjust
1 4
3 2
4 1
2 3
Note how the first column is the firing order, and so is the second (but
shifted by two cylinders or one crankshaft revolution).
This technique actually works for any 4-stroke engine with an even number of
cylinders, including 60 and 90 degree "V" engines. You turn each cylinder
in the firing order to where both valves are open, then adjust the cylinder
that is 180 degrees away in the firing sequence.
Randall
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