1984 Mercury 75 hp bogs down under load

[fashon1]

I am having trouble w/ my 1984 Merc 75 hp. on my 17' fish /ski boat, I just bought from a friend.<br /><br />The motor starts, idles fine and revs well in netural.<br />When I put it in gear it bogs down after 1500 -2000 rpm. and will just about die out...<br /><br />I removed the engine and carb cover. The upper carbs throat is very wet and drips fuel while running. The throttle and choke seem to be woking correctly. I have checked the fuel filter, fuel lines and bulb. The fuel could be 6 months old w/ stable in it.<br />I think the upper carb is way to rich and has a stuck float or needle valve and is flooding the motor under load.<br /><br />To confirm this I ran the motor under load (driving boat in the water) w/o the carb cover and it accelerates great to full throttle. <br />( plenty of air through the carbs to lean it out )<br /><br />I could use some advise or suggestions to make sure I am correct before I remove the carb and rebuild it as well as replace the gas.<br /><br />Thanks for the help.

 

[snapperbait]

Re: 1984 Mercury 75 hp bogs down under load

Mine has pulled this trick a time or two... The culprit, no fuel in bottom carb due to a stuck needle..<br /><br />Think you'll find that rebuilding the carbs is the best bet.. The job is fairly easy and kits are cheap..<br /><br />If anything, i'd say it may be starving for fuel.. Pull the drain plugs on the float bowls and see if fuel comes out.. <br /><br />Make sure all the linkage is moving freely and the carbs are opening all the way... Also check to see if the ignition is advancing all the way to the stop at full throttle..

 

[fashon1]

Re: 1984 Mercury 75 hp bogs down under load

Originally posted by snapperbait:<br /> Mine has pulled this trick a time or two... The culprit, no fuel in bottom carb due to a stuck needle..<br /><br />Think you'll find that rebuilding the carbs is the best bet.. The job is fairly easy and kits are cheap..<br /><br />If anything, i'd say it may be starving for fuel.. Pull the drain plugs on the float bowls and see if fuel comes out.. <br /><br />Make sure all the linkage is moving freely and the carbs are opening all the way... Also check to see if the ignition is advancing all the way to the stop at full throttle..

 

[fashon1]

Re: 1984 Mercury 75 hp bogs down under load

Thanks for the help. <br /><br /> I did not see or feel drain plugs or screws in my float bowls. I thought there should be one in each.