1984 85hp Force, Stator or trigger or ???

jav8tr

Cadet
Joined
May 10, 2004
Messages
6
I have a 1984 85hp Force that the bottom cylinder lost spark. It has two black CDI’s with quick connectors. I can get the bottom coil/plug to spark by switching from one cdi from the other. Also when I switch the stator connectors around spark goes from middle to bottom. So the bottom plug/coil/cdi will produce by switching stator connectors. Pulled flywheel, and don’t notice anything unusual with stator other than lot of the wax has melted or gone. What can go wrong with stators? One thing I notice is magnets on the flywheel facing stator are both strong, but the magnets on the inside facing the trigger only one side is strong, the other doesn’t pull a screwdriver unless I put inside next to where the shaft is, then it will pull some, but not on the side facing trigger. Can these magnets go bad? Any ideas?
 

jav8tr

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May 10, 2004
Messages
6
Re: 1984 85hp Force, Stator or trigger or ???

This is a model #856X4L Force engine. Coils/CDI's and plugs all function when stator connectors are switched with one another. Trigger wires all seem to test ok with ohm meter(static, off engine).Anyone know about the stator or the magnets on flywheel?
 

jav8tr

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Joined
May 10, 2004
Messages
6
Re: 1984 85hp Force, Stator or trigger or ???

After putting parts back together ( not tightened down) and hand turning flywheel with wrench I can get ac output from the two yellow stator wires, none from the blue with a standard meter. Can't seem to see anything from trigger wires other than good continuity from a ohm test.<br />Does lack of ac output on blue stator wire mean it is bad? and I would still like to know if both magnets facing trigger should both pull stong from both sides
 

SlowlySinking

Master Chief Petty Officer
Joined
Oct 31, 2002
Messages
897
Re: 1984 85hp Force, Stator or trigger or ???

Hi jav8tr, here's what the Force Manual says about the ignition system, <br /><br />"IGNITION, GENERAL<br /><br />The 85 and 125 H.P. have a magneto impulsed - CD ignition system; an alternator system and an electric starting system.<br /><br />Ignition System (Prestollte). Rotation of the charging magnets in the flywheel creates a rotating magnetic field which cuts throught the windings of the stator and generates 225 volts AC. This voltage is fed to the C-D module, where it is converted to 225 volts D.C. by a full wave rectifier. The 225 volts D.C. is then stored in a capacitor (located in the C-D module). As the timing magnets rotate, they build up a magnetic field. When the flywheel reaches the proper position, the magnetic field collapes and induces a 2 volt maximum pulse in the trigger coil. This 2 volt pulse causes an electronic switch (located in the C-D module) to close which, in turn, allows the 225 volts on the capacitor to discharge into the ignition coil primary windings. The coil steps up the 225 volts to 25,000 to 32,000 volts. This voltage is fed to the spark plug where it ignites the fuel charge.<br />Turning the key switch to the 'off' position shorts the C-D module to ground and stops the 225 volt output."<br /><br />Since the trigger coil voltage is 2 volts this may explain why it didn't register on your meter.
 

jav8tr

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Joined
May 10, 2004
Messages
6
Re: 1984 85hp Force, Stator or trigger or ???

OK, thank you. I will study this some more and report back.<br />jav8r
 

jav8tr

Cadet
Joined
May 10, 2004
Messages
6
Re: 1984 85hp Force, Stator or trigger or ???

Thanks all, traced problem to stator, replaced with used from ebay, boat works great!<br />jav8tr
 

choskin

Cadet
Joined
Feb 25, 2004
Messages
22
Re: 1984 85hp Force, Stator or trigger or ???

Service manual points out that to get the correct voltage readings from a stator or a trigger a special volt meter is needed.This is a peak voltage meter. As the voltage is a narrow pulse of voltage that peaks above 200 volts from the stator, a normal volt meter will at best show a kick in the needle or if a digital meter maybe nothing. An oscilloscope would show this waveform, but who has one of these lying around!
 

eurolarva

Rear Admiral
Joined
Jun 24, 2003
Messages
4,182
Re: 1984 85hp Force, Stator or trigger or ???

Craig. If you type DVA Marine tester in yahoo search engine you can find various adaptors that will work on most digital volt meters for around 35 bucks.
 

choskin

Cadet
Joined
Feb 25, 2004
Messages
22
Re: 1984 85hp Force, Stator or trigger or ???

Thanks eurolava,Here I was trying to explain why sometimes we measure a voltage and get no reading.An adapter sounds like the cheapest solution Though.personally I can borrow a peak volt meter from work.
 
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