Re: Question for rodbolt
no worries. the 25" motor has a bushing above the waterpump area in the midsection that has backflipped many techs.<br /> the etlf really does not correspond to the alpha designations.<br /> however its rather inconseqential as the L usually designates 20" and an X will desigignate 25".<br /> however the fact you have spark tells me the trigger circuits are working, now we have to find the voltage loss,if any, on the CDI capacitor charge/discharge circuits.<br />if you motor has been upgraded or has factory installed red spark plug caps remove and test them.<br /> test the low spped charge coils for proper resistanceBr-R 1050 ohms then test each leg Br-ground and R to ground for any continuity, resistance should be infinite(open circuit) the test the high speed coilsBlue to Br/R 24ohms and test each leg to ground. the output voltage loaded at cranking sp3ed should be about 75V low speed and 14 high speed, unloaded will be 85 and 14. the CDI must be loaded to test the output, loaded cranking with a spark tester should be 58V loaded and 0V unloaded. all V tests must be done with a PEAK reading type meter or with the DVA adapter.<br />the coil secondary resistance, red caps removed, should be 3.8Kohms, red cap resistance is 5Kohms.<br /> the system is fairly simple. it consists of a rotating magnet(flywheel) creating an ac current wich is recitified and stored in a capacitor, the flywheel inner magnet creates an ac voltage which is used to turn the SCR to the on state allowing the capacitor to discharge through the ign coil primary windings. as its sparking and the fact the trigger circuits have no affect on CDI output voltage I would say the trigger circuits are ok. carfully test all CDI and battery grounds. you really need to make or buy a spark tester capeable of testing all 6 at once. I have posted several times on how to make a cheap easy tester at home. DO NOT use carbon plug wires for your homemade tester. use steel core.<br /> that motor may or may not jump a 7/16ths gap at cranking speed, the 90 up models have the CDI output increased to 105V, at the 84-89 75V output it gets iffy, the system quits at about 65V CDI output. does not allow much room for degradation.<br /> but try testing all with the plugs out, if it improves look for slow cranking speeds due to starter circuit degradation or starter brush wear, its also possible the flywheel magnets are getting weak. the old ear test sometimes fools ya on cranking speeds.<br />many motors sound good and will pass a spark test with all plugs removed but fail the test with the plugs installed. has bit many a tech.<br />but its imperative to test all six at once.<br />do the test with plugs in and plugs out to see if the results change.<br />if there is a significant improvement with the plugs out look for stater circuit,not starter acutating, issues.<br />means a voltage drop test. not just a battery voltage test.<br />from the engine block to the -batt terminal,not cable end, should be less than 1Vdc and from the starter terminal to the +batt terminal,not cable end, should be less than 1Vdc any other results mean ya gotta go hunt. if battery voltage across the terminals drops below about 10.5 Vdc look at the battery. use the 6 spark spark tester with the plugs installed and the sparktester attached for all cranking tests. you always want to control spark when any cranking tests are performed as the fuel/air mix expelled from the plug hole is a chemically correct mix that an errant spark can and, occasinally does, ignite.<br />EFI motors are notorious for it as some of the PRIME start yammies.<br /> its funny to watch a tech with his hairs aflame
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