Re: 1985 40 hp Mercury wont stay running
I have a 79 2 cyl 40 hp it isn,t hard to rebuild the fuel pump if it hasn,t been done lately I recommend it before setting out on the water. Take down the fuel filter you see on the side of the motor there is a screen inside make sure its clean, it unscrews counterclockwise. Fuel pump kits are relatively inexpesive you can get them at a dealer or eBay or here on iBaots. This should solve that problem, but if this engine hasn,t been serviced in a while I would drop the lower unit and rebuild the water pump as well. This must be done at least every 2 years used or not, but I do mine every year on the LU with a new impeller. Now on these engines, at least the older ones, the wires on the stator under the flywheel become corroded. Check to see if you have corrosion in that area on the left side from the front of the motor. Do not run this, or any outboard engine for more than a few seconds out of the water! When you do get the motor started check to see if it pees out the back. It may take some time before the thermostat opens. I removed mine due to a leaking popit on top of the thermostat. This means either you have a blockage from junk in the motor, a blown impeller, or that the impeller is simply worn out. This should get you quite close to being ready other than the timing carb adjustment and a link and sinc on the linkage
