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93 300 XP, had no spark in all 8, put a new stator & power pack in, spark in 7 plugs, Then put new coil & coil wire on dead one, still no spark, changed spark plug to rule that out, Trigger/Timer base is a CDI, we did not replace this, it looks pretty recent. what is our next step?
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Is the engine actually running on 7 cylinders... OR... are you speaking of no spark during a spark test?
If actually running on 7 cylinders... and you already eliminated the stator and coil as problems... what's left if the timer-base... BUT... it could simply be one of the pins or sockets has backed out a bit in those rubber connections resulting in a poor conduit. Also the wires have been know to break off from those pins/sockets... and the wire would be held in there by pure friction. happens quite often.
Check the ohm reading on that timer base... all the sensors should read identical.
If, on the off chance that you're doing a spark test with all the spark plugs in... that's a no no as that drags down the rpms, and the engine has to be cranking over at least 300 rpm for the stator to energize the powerpack's capacitor. A lower rpm results in weak, erratic, or no spark/ignition regardless of the condition of the components.
A spark test demands that "all" spark plugs be removed.
Let us know what you find. -
Thanks Joe,
We had brand new spark plugs in and after running the boat in the water for 30min and it ran but was a little rough we pulled the spark plugs, the top right plug looked like new and was not used at all. We will check the connections and ohm's on the timer base.Comment
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Pertaining to a spark test...................
All s/plugs removed..... a spark tester used whereas a air gap of 7/16" can be set for the spark to jump.
The spark should jump that air gap of 7/16" with a strong blue lightning like flame... a real SNAP! Nothing else will do. Does it?
No tester?... available at most auto supply stores or you can built your own as follows:
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(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
This can obviously be modified to a 6 or 8 cylinder setup tester.
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Hi Joe, I went to unplug the connectors between timer & power pack and you were right, a pin had backed out, we held it in place while plugging it in and now have spark, took the boat out today and it runs great, Thanks again.Comment
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You're one of the lucky ones... glad I was here to help. That $14 is still in your pocket!
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Motor is running but Idle will not come down below 2200 rpm, trigger was replaced before me, could the timing make it idle so high?Comment
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Before doing anything else.... remove the throttle cable from the engine's linkage. This is to see if the throttle cable is holding the linkage in an advanced position.... allowing the throttle to close down further?
Also check to make sure that "all" the throttle butterflies are closed shut at the idle setting... and that they "all" open at the same time (when the scribe mark of the cam is dead center with the throttle roller).
Let us know what you find.Comment
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