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HELP on exhaust/compression stroke!


itechengineers
06-07-2004, 12:43 PM
hello everyone.

im studying timing belt swaps on honda motors.

I found out that there are 2 sets of strokes to complete a full set.

the #1 cylinder (like all the others) has an exhaust stoke, then a compression stroke (on the compression stroke, the spark plug will fire).

I found out that you need to have piston #1 at TDC with the compression stroke.

How do you or can you tell if piston #1 is TDC with the exhaust stroke or the compression stroke?

when you use a wrench and hand turn the crank pulley, does a full 360 turn with it represent that piston #1 has already went through TDC on exhaust and TDC on compression? OR would it be 2 full crank turns on the pulley?

and on the distributor, if you pull off the cap and look at the rotor, while cylinder #1 is at tdc for spark / compression stroke, does that mean the contacts on the rotor should fire by the plug wire #1 contact?

IM hope i wasnt confusing, im just trying to leanr about distinguishing between the exhaust stroke and compression stroke on the motor. obviously, you'll encounter problems if piston #1 fires on the exhaust stroke instead of the compressions stroke (right?)?

thanx

civickiller
06-07-2004, 02:29 PM
well if you just putting on a new timing belt, it dont matter on what stroke the cylinders are on as long as your get it to tdc, via ligning up the marks on teh crank and on the cams.

and yeah if the rotor should be at #1 contact

PunkAlex
06-07-2004, 06:55 PM
which youre dealing with the shortblock, there are only two positions that matter, TDC and BDC. Determining which stroke an engine is on is all a product of the cylinder head/cams.

itechengineers
06-10-2004, 04:04 AM
thanx for the help and info!

civickiller
06-10-2004, 10:47 PM
if you want to distinguish then look at the valves and rocker arm, if the valves start to open on the exhaust side then you know yoru on the exhaust stroke.

yes 2 full turns of the crank is one complete combustion revolution

is there anything else you want to know ?

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