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View Full Version : 1992 240sx: How do you know you are tdc for the compression stroke?


surreybc
08-03-2008, 04:50 AM
Some people say to remove cyl one sparkplug and put a screw driver in hole and when screwdriver is sticking out the most that is the compression stroke. Is there also an exhaust stroke where the piston comes up to top of cylinder?

"First you need to find Top Dead Center (TDC) for the compression stroke in order to time the ignition distributor. To find TDC, remove #1 spark plug and disconnect the ignition coil wire. Have someone tap the ignition switch start position to slowly crank the motor while you put you hand or thumb over the spark plug hole. When you feel the compression, stop. Now look down at the timing pointer at the front pulley. It should be pointing to ZERO. If not, manually turn the motor clockwise or counter-clockwise by hand until it's pointing to ZERO. Now determine the #1 plug wire location on the distributor cap. Mark that location on the distributor body. Now insert the distributor into the block, meshing the gears so that the rotor ends up pointing to the mark you put on the side of the distributor body. You now are timed close to correct; you should be able to start the motor.
Before starting the motor, set up a timing light so that you can set the timing to spec. Disconnect the TPS harness connector. It's located on the passenger's side of the engine just above the throttle assembly. Start engine and set timing to 20 degrees BTDC. Stop the engine. Reconnect the TPS harness connector'

Flybert
08-03-2008, 04:53 AM
Put your hand over the spark plug hole when you are cranking it over. When you feel or hear air as it pushes against your hand, you are on the compression stroke.