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98 johnson spark issue? Video

kimcrwbr1 said:
That dont look like an adjustable air gap tester. You want the spark to be able to jump a gap of at least 7/16 inch brite blue snap. Have you done a compression test? Give us some compression numbers along with a model number of the motor. Pull all the spark plugs and check the compression with the engine cold. To protect the ignition system ground all the plug wires while checking spark gap and compression.
Click to expand...

No it's not an adjustable tester. It's just to show if it has spark. And yes I've done a compression test already. 110 psi per cylinder. It is a 98 johnson 115hp v4. I can put the spark tester on any of the plugs and it shows the same miss when the motor stumbles not just one the one I took the video on.
 
The spark, with all spark plugs removed so as to obtain the fastest cranking rpm, should jump a 7/16" gap with a strong blue lightning like flame... a real SNAP! The 7/16" gap is important.

To simply have a spark, light blue, yellow, whatever, that jumps a 1/8" or 3/16" gap just doesn't do it on those high performance outboards with Mahgneto Capacitance Discharge ignition.

No tester... can't locate a proper tester? Build the following:

********************
(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

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay auction at:

http://shop.ebay.com/Joe_OMC32/m.html?_dmd=1&_ipg=50&_sop=12&_rdc=1

 
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