I can find the timing mark I need riset the time on nissan pickup 1986 2wd

Hi,
the timing mark is usually a white painted groove on the main fan belt pulley.
Look for another plate with a a couple of lines or grooves mounted on the engine block right behind the fan belt pulley wheel.
Assuming you have hooked up your timing light per the instructions...When you shine your timing light at this area you are looking to see if the pulley mark lines up with the timing mark on the engine block plate when the engine is at a specific idling speed and the distributor is adjusted to make the timing mark line up when cylinder 1 is firing.
The engine block plate is often marked as 6 deggrees BTDC (before top dead centre). The middle mark is usually top dead centre. (the timing figure could be anything eg 8 deg BTDC..I am just usually an example figure)
See here for more info:
http://www.ehow.com/how_5038331_work-timing-light.html
http://autorepair.about.com/od/tools/a/tools_timinglit.htm
http://everything2.com/title/timing+light

Regrds, Steve
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