You have a point type Mercruiser distributor and it will not fire!  What do you do?

1) With the ign switch on check for voltage at the coil + terminal, This can be done with a 12 v light between the terminal and anything grounded, or a 12v meter or in emergency a screwdriver from the + post to the block (look for spark).

2) If no spark run a jumper to the + terminal and try cranking.  If it starts drive home and then check the ign lead from the key switch while safely in the driveway.

3) If you have 12 volts pos on the coil but no fire, disconnect all wires from the neg(-) side of the coil except the wire from the distributor. Try for fire.  If the ignition runs with these wires disconnected the ign system is good but either the wire to the easy shift switch is grounded or the tack lead is grounded.

4) If this procedure does not produce results leave these wires off for a while and do the following test.

5) Remove distributor cap and rotor, disconnect the coil wire from the cap end of the wire and hold it close to the block (1/4") and bump the engine until there is an open gap in the points.

6)  If a screwdriver is inserted between the points and released several times a spark should be emited from the coil wire. if not remove the condenser wire and coil wire from the pionts and hold them between the thumb and forfinger and touch and release the wires to the base plate.  If no spark occurs replace the coil and condenser.

7)  If the wires touching or the screwdriver trick get a spark but spinning the engine does not, replace the pionts and retest. the cranking for spark.

8)  When the wires are in your fingers and touching the plate, no part of the system matters except the cond and coil, and the voltage, forget any other condition, it will fire no matter what..

9)  Once you get fire with your fingers put the wires back on good points and spin the engine for spark, if you did not ground the wires to the mounting plate the fire will continue with points installed.

10) Replace rotor and cap and test for fire from the wires.  If the fire from the wires is not as stromg as the fire from the coil replace cap and wire set. Chech the firing order.

11)  With #1 wire removed bump the engine with your finger on the plug hole.  When the pressure comes out of the hole the engine is on compression stroke.

12)  With cap off notice which direction the rotor turns and continue the compression stroke until the timing mark approaches the top center mark, if you were compressing from the hole this will be TOP dead center (TDC).  Set the mark just before top center at the proper mark for the recommended timing. At this point the rotor should be pointing at the #1 wire and the others are inserted into the cap in the direction the rotor was turning acording to the fireing order.

13)  If you rotart the distributor base in the same direction until the points close and reverse until they just break the timing will be set where the damper is sitting, and if you set it at the proper place the engine will be close to the proper initial ignition timing, set the piont gap and set the timing with a light.

14) DON'T FORGET TO RECONNECT THE WIRES YOU REMOVED FROM THE NEG (-) SIDE OF THE COIL

15) Good luck.            BACK TO TUNE UP PARTS  im tired of this show me ELECTONIC CONVERSIONS