1988 force Full throttle only 3500 rpm

robman2100

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I have a force 125 that at full throttle is only going to 3500 rpm sometimes 4000. When I got to shift forward or backwards it needs to be titled for it to start going and still low rpm... what could cause these issues. Engine is not running rough just won't make the power.

The picture is at full throttle
 

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puffitu

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Could be any number of things. Start with basics I.e. compression and spark. Eliminate one by one so there’s no cross confusion. Check all electrical connections; they do corrode and or break without being visible until you go diggin. Carbs Link n sinc ?? Anyone mess with timing. Fuel pump diaphragm maybe. As I said, one by one until you find what the issue is. Sounds like a pain in the rear but the only way you really find the issue and prevent it from happening again.
 

robman2100

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Could be any number of things. Start with basics I.e. compression and spark. Eliminate one by one so there’s no cross confusion. Check all electrical connections; they do corrode and or break without being visible until you go diggin. Carbs Link n sinc ?? Anyone mess with timing. Fuel pump diaphragm maybe. As I said, one by one until you find what the issue is. Sounds like a pain in the rear but the only way you really find the issue and prevent it from happening again.
Compeasion is 130 all cylinders. It is idling in neutral at 2000rpm. Whats weird is randomly at full throttle it is at 4500 rpm then just opens up and it goes but the moment I throttle down and it goes back to lower rpm and then it won't open up again until randomly wants to go.
 

Redbarron%%

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Could easily be a bad connection or wire to one cylinder from the trigger.
 

racerone

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Idling / shifting at 2000 RPM will be hard on clutch dog and gears.-----Do the repairs before you damage those parts.-----Say there is a blockage in one carburetor , then no fuel means no oil !-----Or you have ignition issues.----Does spark jump a gap of 3/8" ( 1 cm ) on all leads ?
 

robman2100

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Idling / shifting at 2000 RPM will be hard on clutch dog and gears.-----Do the repairs before you damage those parts.-----Say there is a blockage in one carburetor , then no fuel means no oil !-----Or you have ignition issues.----Does spark jump a gap of 3/8" ( 1 cm ) on all leads ?
Not sure will check next.
 

puffitu

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Compeasion is 130 all cylinders. It is idling in neutral at 2000rpm. Whats weird is randomly at full throttle it is at 4500 rpm then just opens up and it goes but the moment I throttle down and it goes back to lower rpm and then it won't open up again until randomly wants to go.
Idle should be at around 1200/neutral and 700-800 in gear. Did you do the link n sinc carb as the sticky goes through in the beginning of this forum??-very important! Also check the recirculating system. If it’s sucking air somewhere then they’ll be def loss of power or intermittent...Check ALL wiring relating to coils packs and stator wires. I had found couple loose wires which were wiggling out of their connectors; replaced connectors and instant improvement. AGAIN-do one by one and try the motor otherwise you’ll never know what the issue was if you did a bunch of things. I know it sounds like a pain these motors do require time and patience
 

robman2100

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Idle should be at around 1200/neutral and 700-800 in gear. Did you do the link n sinc carb as the sticky goes through in the beginning of this forum??-very important! Also check the recirculating system. If it’s sucking air somewhere then they’ll be def loss of power or intermittent...Check ALL wiring relating to coils packs and stator wires. I had found couple loose wires which were wiggling out of their connectors; replaced connectors and instant improvement. AGAIN-do one by one and try the motor otherwise you’ll never know what the issue was if you did a bunch of things. I know it sounds like a pain these motors do require time and patience
Ended up being the float was not working correctly and the bowl was overflowing. Took it to a shop and they are rebuilding them now.
 

puffitu

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So...the float lost buoyancy or pin stuck? What exactly was it that the shop told you? If you don’t mind me asking ..
 

robman2100

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So...the float lost buoyancy or pin stuck? What exactly was it that the shop told you? If you don’t mind me asking ..
He was saying a couple of issues. It is now running like new.. The first was that the carburator float was not closing off the fuel inlet when the bowl was full. (Bulb was soft and would continue to let more fuel into the carburator instead of getting tight. ) so it was basically flooding.. second issue was the timing was off. And it just needed an overall service. 500 Dollars later and im home free. Thanks everyone for your help!
 

puffitu

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He was saying a couple of issues. It is now running like new.. The first was that the carburator float was not closing off the fuel inlet when the bowl was full. (Bulb was soft and would continue to let more fuel into the carburator instead of getting tight. ) so it was basically flooding.. second issue was the timing was off. And it just needed an overall service. 500 Dollars later and im home free. Thanks everyone for your help!
Hey good to know-thanks for posting back. I was chasing down a similar issue; floats out of adjustment and lacked power at wot. Took carbs apart and both were of especially my top carb. Ive checked and adjusted them myself before and stumped why they would’ve gone out whack...Now running very good. My next thing is to check the timing; I never have put a light on it ..happy boating
 

jerryjerry05

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Puffit: if you've never touched the timing???
Now isn't the time.
The timing won't jump or change unless you
do something to change it.
 

puffitu

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Hey Jerry
You might be right; why fix if it ain’t broke!? I’m just getting a slight surge/hesitation at about 4300 rpm so my little brain goes right to timing since that’s about the only thing I haven’t checked. Thoughts? Sorry mods...
 

Redbarron%%

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The timing can't be much simpler. Set the low and then check to see that the WOT is correct. It (in my opinion) is OK to do it at the dock, tied securely with an observer. The static timing should put you pretty close.
 
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