intermittent spark

[love boat]

I have a 1987 force 125 took it out yesterday ran decent started and stopped the engine a half dozen times sat anchored for 45 min went to start it cranked strong no spark checked fuses all looked good went to start it today fired right up any suggestions??ps this is the second time this has happened

 

[gm280]

Sounds like it could be wiring connections or even the ignition module(s) going out. I would start with removing all the connections and cleaning them to bright shiny metal again and then reconnecting them tightly. Also the battery AND the ground wires and connections on the engine. After you do that, see if you still have any problems. If so, then you could have some ignition parts going bad. JMHO

 

[pnwboat]

Make sure the Kill switch is not bad. You can pull one of the wires off of the Kill Switch and that will disable it. It should read "OPEN" with an OHM meter in order for the ignition system to work.

 

[jerryjerry05]

gm280 was right about the connections.
​Clean, replace everything.
​The blades on the kill switch corrode under the plastic and the connections fail.
Replace all wire connectors and sand the blades and WD or dielectric grease.
​Some Forces had a fuse in the panel under the dash they corrode and no spark??

The connectors on the motor probably 50 need replacing, cleaning.

 

[love boat]

disconnected both wires on kill switch still no spark looked closely at all connections took a couple off very clean you can literally eat off this thing the only part that is a little sketchy is the fuse block has old style glass fuses its a little rusty in some spots

 

[kbh121956]

Use a OHM meter on your fuse block. Mine looked great but most of the fuses were dead. I took them out and cleaned the clip connections on the fuse box panel.

 

[love boat]

I replaced the fuse block with a new one no luck plus no wires in the fuse block directly relate to the ignition they go to the radio,bilge,tilt,fish/gps if the ignition switch were faulty could that cause a no spark condition the boat cranks but could it still be faulty

 

[jerryjerry05]

Only certain models had a fuse in the block for the motor.
​The top posts in this forum have tips on things like this.
Read them and maybe something will help.

​Also a stator or the regulator can go bad in an instant.
outboard ignition dot com or CDI Ignition has test procedures for your motor.
​The base tests can be done with any meter but an analog meter with a DVA function is best for all the tests.

 

[pnwboat]

Just keep in mind that the battery voltage and fuse block are not involved in generating ignition spark. You can disconnect the battery and wrap a rope around the flywheel and pull start the motor. It will run just fine. The ignition system is self contained. The only thing that the battery voltage is used for is the starter, any accessories and the Tilt/Trim pump.

If you have intermittent spark, and you've eliminated the Kill Switch by disconnecting it, then take a look at the wiring on the terminal strip where the ignition system components (CD Modules, trigger, stator etc) are connected. Take a close look at the spade lug connectors. A lot of these connectors have a short piece of black heat shrink over the crimp/soldered area where the wire is connected to the spade lug connector. It's not uncommon for the wire to break right at this joint. The black Heat Shrink covers that area, so you cannot see the break. The Heat shrink holds the wire to the spade lug connector so you get the impression that the connection is solid, when in fact it's intermittent or maybe hanging on with a single strand of wire.

The trigger wires a more prone to this problem as they are made up of very fine strands. If you have the black heat shrink on your connections, that's a good place to start.