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Force 1990 90HP Rebuild Probs

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walleye1

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"Hi Guys, rebuilt the powerhea

"Hi Guys, rebuilt the powerhead on my Force 1990 90 HP. Bored the all the holes over 30 thou, new pistons, rings, bearings. Finally got it all back together. Can get it running but its rough, spits and sputters like crazy, won't rev up over 2 or 3 thou. I'm mucking with the timing now. Any ideas? Thanks. Mark"
 
Do you mean synchronize the ca

Do you mean synchronize the carbs? And what do you mean by link it? This engine has actually been pretty good to me. 17 years old and never any maj probs until last month when it puked out a piston ring on #1. Was running good all summer before that. Would you have to re-jet after a rebuild like this?
 
"Mark, I see you found the sit

"Mark, I see you found the site. Just-In-Time is great with the larger motors. Grab ahold of him for advice whenever you can..."
 
"Tks for the advice. Sync'

"Tks for the advice. Sync'ed up the carbs, no change. Now no spark on 1 and 3! Believe it or not this thing will run on 1 cylinder! Starting to suspect stator. Checked it out with voltmeter IAW my Clymer manual. Says it should crank 210 volts across each pair of wires. I can't get over 2 volts on either pair. Just doesn't seem right. Everything was fine before the meltdown. Must be doing something wrong? Any thoughts. Gonna take a sledge hammer to it soon. Thanks."
 
"Mark, losing spark on 2 is mo

"Mark, losing spark on 2 is more likely the trigger - bad stator would be no spark on all 3..."
 
"Gray,
Agreed but the stator

"Gray,
Agreed but the stator doesn't check out. The manual says the troubleshooting order is stator/trigger/cd mod/coil. Can't get past the stator. Like I said in a prev post, I can't get hardly ANY voltage across the 2 pairs of stator wires. I just don't see how it would have flashed up at all if the stator was that bad. Maybe the flywheel? Mark"
 
"Yes Mark, that doesn't ma

"Yes Mark, that doesn't make sense. If the stator produced enough for one cylinder, should be good for all of them - it doesn't care where the charge goes - it charges the capacitor in the switchbox and the trigger tells it which coil to fire.

As long as the magnets stayed in place on the flywheel, that shouldn't be your problem either.

Your stator should have low and high speed windings - you should get almost no voltage out of the high speed pair at cranking speed. Did you try a simple continuity test vice just the voltage check?"
 
"What's the switch box, th

"What's the switch box, the CD Module?
I'm just going by the book. Its says I should get 210 volts across each pair of stator wires while cranking. Its pretty specific "Set the meter on the 400 DVA scale and connect test leads to the two disconnected stator wires. Crank the engine while observing the meter. Peak voltage should be 210 volts or if reading is intermittent, replace stator." And the same for the other pair of wires. It doesn't say anything about a continuity test. Do you know what the resistance would be? Mark."
 
"Mark, don't have the exac

"Mark, don't have the exact specs but you should have probably between 3000-4000 resistance (3-4 on the x1000) - or almost complete continuity.

What you are looking for primarily is a (dead) circuit (not making any power).

Also check for continuity between the leads (each) and ground on the head - which would indicate that the stator is simply grounding out - you should have almost no continuity there...

And yes, earlier post was referring to your CD box - called powerpack (omc) and switchbox (merc)...."
 
"If your stator is bad however

"If your stator is bad however, you may want to look at other options - Merc want's over 600 bucks (up here) for that part...."
 
"Mark, one other question - ar

"Mark, one other question - are you using a DVA adapter on your meter?. The stator produces AC - it's your CD module that rectifies it to DC and stores it.

Without the adapter, your meter is trying to measure AC as DC and would give you a very funky reading - hence the resistance tests to check for bad windings....."
 
try replaceing the power pack

try replaceing the power pack that conects to the two dead cylinders [ just had to do mine ]
 
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