120 sportjet

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dreman30

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Hi everyone, noob here. I have a 1995 Sea Ray fx with a 120 sport jet. New stator from CDI Electronics and trigger also new from CDI Electronics. It fires up nice and idles good but when i go to take off it falls flat in its face, won't go over 3000 RPM. checked my timing and all is good, throttle is nice and snug, I've been working on this thing for a week with no progress whatsoever. Any ideas as to what would be my problem????
 

QBhoy

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Many things may be to blame. But a good start would be to look at condition of fuel...is it old ? Have water in it ? Filter clear and clean ?
How are the carb(s) jets blocked ?
Spark plugs good and correct gap ?
Does the sport jet have power valves in the exhaust ? Are the servos sticking or are the valves gummed up ?
Just a few simple starters for 10
 

dreman30

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Thank for the response, I tore down both carbs and cleaned em out, new fuel lines installed and found the problem. I have 2 coils that aren't firing, bottom 2 cylinders. Ordering a new coil pack and see where i'm at once they are changed. Hopefully that's the last of my problems!Oh and the reed valves are brand new.
 
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dreman30

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So i just noticed something online, i had original red stator with the brick thing, now with the black stator do i remove the brick? Could this be my problem with it??
 

maicoman

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Nov 10, 2010
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Another Sport Jet only the sportier one.My suggestion lose that POS as soon as possible,it will never be any good.Sad but true !
 

QBhoy

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Compression check it. Unfortunately they don't have a reliable reputation, those engines. As with all but the most modern 4 stroke jet boats. Even they don't sit well with me. Tiny wee engines screaming within an inch of their life squeezing 250+ horsepower out a 1800 cc engine. Doesn't bare thinking about !
 

Redbarron%%

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The black stator does not use the candy bar adapter.
The adapter goes with the red stator that has a single set of windings where the black one has a high and low speed set.
Down load a copy of the manual and see what is there.
I had a red stator and the candy bar adapter abd replaced my switch box and coils with the CDM modules and late model harness.
My problem was that the trigger coil was bad on #3 cylinder \.
Personally I like my setup with the CDM modules from a 200 hp Mercury, a three cylinder harness from a 50 hp Mercury and the red stator.
A lot of boxes that give trouble are now not on my Sport Jet, but in a box under the workbench.
One thing to make certain of is that if you have a bad rectifier/regulator it can blow the switchbox when you shut down the engine and a no start after that.
I replaced my regulator with a Ducati (Chinese copy) regulator/rectifier for $28.00 and it takes care of the voltage going over 15 volts with a maintenance free battery.
I think the big problem with the Force (by Mercury) engines is the old electrics.
This is why my 90 hp now has late model Mercury ignition and modern MOSFET voltage regulator.
 
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