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No spark

you need to find serial# on transom plate . Not enough information provided. first time out,has engine been sitting forever? How have you tested for spark??
 
B0045927
I tested for spark by taking the plugs out then holding the end against the thread of the spark plug hole whilst my pal pulled the pull start
 
The proper way is to stick the spark plug in the wire and hold it in your hand then have your friend pull the rope:) Then pull the flywheel and give the coils and points a good visual. If the coils are cracked they need replaced. I just rebuilt a 1984 4hp and these little motors are real sensitive to ignition timing. The best way is to set the new points at exactly .020 then tighten the flywheel to spec. Hook a timing light to any 12 volt battery and put it on a plug wire then point it at the two marks on the points plate while ideling the line on the flywheel should be inbetween the two marks on the plate. Check the other plug wire the same way. To adjust timing you change the point gap it is time consuming but once you get it correct you can dial in the carb properly. As a side note you can let your friend hold the spark plug while you pull the rope as long as he is not bigger than you, the proper spark test is done with a open air spark gap tester. It must jump a gap of at least 1/4 inch brite blue snap. You can put the plug in the wire and hold it 1/4 inch from any good ground as someone pulls the rope. It is best to use a good pair of insulated pliers to hold the plug. Otherwise get a good spark gap tester from any auto part store.
http://cgi.ebay.com/ebaymotors/Igni...271776?hash=item488df4bc60:g:thUAAOSwneRXRNBB
I bought one of these and use it all the time!
 
(Spark Tester - Home Made)
(J. Reeves)

You can use a medium size philips screwdriver (#2 I believe) inserted into the spark plug boot spring connector, then hold the screwdriver shank approximately 7/16" away from the block to check the spark or build the following:

A spark tester can be made with a piece of 1x4 or 1x6, drive a few finishing nails through it, then bend the pointed ends at a right angle. You can then adjust the gap by simply twisting the nail(s). Solder a spark plug wire to one which you can connect to the spark plug boots, and a ground wire of some kind to the other to connect to the powerhead somewhere. Use small alligator clips on the other end of the wires to connect to ground and to the spark plug connector that exists inside of the rubber plug boot.

Using the above, one could easily build a spark tester whereas they could connect 2, 4, 6, or 8 cylinders all at one time. The ground nail being straight up, the others being bent, aimed at the ground nail. A typical 4 cylinder tester follows:

..........X1..........X2

.................X..(grd)

..........X3..........X4
 
If you do exactly as these two above are suggesting, you may get a painful shock because the electricity will go thru your hand instead of the engine block to get back to ground. You want to take a loose spark plug with the proper gap set already and put that into the spark plug wire rubber boot. It should click into place for a secure fit. then hold the metal shell of the spark plug tightly against any bare metal parts of the engine. with no spark plug in the engine it should turn over more easily, and if the ignition system is working normally, when you crank or spin the engine (should be in a water tank or at least have "ear muffs" to protect the impeller) you should get a nice blue spark from the plug without getting shocked.
 
The original poster likely has the motor running by now.----Post is 2 years old.-----The proper way to check spark does NOT use sparkplug !!
 
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