loss of power under load

[mike sumner]

Cannot get full rpms at full throttle.While on the water sprayed gas in top and bottom carb. Top gave no response, bottom gave surge of power. Had a new carb installed and the other one rebuilt 8 months ago but motor has sat for 5 months. Can anyone list the possible causes besides another carb rebuild because I'm hoping it is something simple.Have new tank,hose and primer bulb, tank is vented.Motor runs fine at idle.I have put this motor on another boat since the last time it ran great, had to disconnect the remote control to get it off the boat,seemed to go back together only one way.'91 40 hp Mercury.Thanks

 

[zj-jeepster]

Re: loss of power under load

let me give it a shot,<br /><br />top carbs might need work but could also be ignition. moisture could be a culprit if it rained heavily recently like it did in jersey. I had simular problem but eventually just dried out and working again.<br /><br />coils get old and loosen up, epoxy cracking or the coil just give up. try a simple continuity test to double check. wet wiring or old deteriorating wiring, especially plug wires. check for arcing during tthe darker hours. higher rpm's need mucho electrical juice.