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96 Mercury 40hp 4cylinder NO acceleration

M

Madoublet863

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Recently replaced the Stator, Trigger Coil , Switch box,rebuilt carbs checked timing marks there are dead one at wot and at idle in gear new fresh fuel all that i have adjusted was idle screws and fuel/air mixture screws to specs; THE problem no top speed engine only revs to 3000rpms and any adjustments to air/fuel mix or to idle screws and these adjustments do nothing need some guidance; next is the hiring of a mechanic but id love to figure this out thanks MATT
 
Compression test ?-------------Reed valves checked when carburetors were off?------------Spark that will jump a gap of 7/16" on each plug lead ?
 
1. Are all 4 plugs firing? Do a WOT run, shut it RIGHT down, and then pull the plugs to find out. Do not let it idle for even a few seconds or you'll waste your time.

2. You might have too much pitch on your prop for the boat. Did it ever run okay with your present set up?

Jeff
 
no wot shutdown check yet on sec thought the stator i ordered could be wrong when i entered my serial num two showed up lol i ordered the cheaper one idk im gonna put my old stator on and check it out wot
in response to the prop statement it ran fine when my neighbor owned it the it quit sparking then i replaced everything but the coils its got me confused i appricate any suggestions thanks matt.
 
okay been reading other post i took my oil injector resovior off but didnt block off any fuel lines or lines running to the oil tank is that where my bog and weak performance with no wot coming from thanks.. matt
 
Hi have you got to the bottom of the problem as I have the same problem used it 4 weeks ago no problems at all washed out with fresh water when we put it in 2 weeks later I am only getting half power 4 cylinder 100hp i have changed fuel pump, fuel filters x3, and spark plugs still no good will rev it's nuts off out the water on a hose pipe good compression on all 4 cylinders can u help at All cheers Dan
 
K40 winding up a 2 stroke outboard in nuetral really proves nothing, and is in fact a big mistake and risks major damage to the engine.---Check spark , must be able to jump a gap of 7/16" on all 4 cylinders.-----Are all 4 carburetors opening up , linkages all attached?
 
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