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125 hp Force

bob_b

New member
"Have a 125 HP Marine force, 2

"Have a 125 HP Marine force, 2cyl,2 stroke, built in 1988. Have no spark at the #1 spark plug. I switched the ignition coil from 1 down to 4, and the coil works fine there. Changed out the Cd box for cylinders 1 & 2, still no spark at #1. Does anybody have a suggestion as to what the problem could be, before I go any further.Started to pull the Flywheel, but pulled the threads right out of the hole with wheel puller and decided to stop and ask for help before going any further. Maybe someone has a suggestion on what to check before I go any further and do more damage. Thank you. Bob. B"
 
"Resistance tests with an ohm

"Resistance tests with an ohm meter between the stator leads.

I'm trying to remember the colours now - think there is a pair of brown leads and a pair of blue (or just blue stripes)(??) - you need to remove them from the terminal strip to test.

You can put both the blues together on one lead of the tester and then check for continuity with the other lead to each of the other two stator wires separately. Should have "minmal" resistance.

The two yellow leads are for recharging the battery and do not affect ignition.

Check all the connections - Force wires are notorious for spontaneously disconnecting themselves from the terminal strips they are supposed to be connected too. Also, if it's an original trigger, the leads are very very fine wire and tend to snap off from the terminal connectors.

Also need to test the trigger leads (all 4 pairs) - they are on the right hand side of the terminal strip - two trigger leads for each cylinder - again remove the pair and test across the pair - should have continuity.

If your continuity looks good, there is one more thing to check. Each one of the CD packs has a (ground) wire that goes across the top of the powerhead (snaked in under the flywheel) to a grounding strip on the side of the motor opposite the main ignition terminal strip). These wires feed over for the ignition kill switch. If you disconnect these two wires and just turn the motor over without starting and spark comes back to number 1, you have a blown blocking diode in the CD pack and you must replace the pack. I don't suggest letting the motor start with these two wires disconnected, because there is no way to cut the ignition without them connected.

These have a poor ignition system at the best of times and the CD boxes do blow regularly as well (and they cost a bundle to replace).

I have also found from experience with these prestolite ignitions that sometimes the resistance tests come back "ok", but when you put a DVA tester on the component (stator or trigger) the part is actually bad - which can lead you to chase your tail if relying simply on an ohm test.

But if the ohm test comes back bad, then the part is definately bad...."
 
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