Hi everyone. I recently picked up this 71’ Evinrude Fastwin 18 Horse. It won’t stay idling for more than 30 seconds. But it will rev up and stay full throttle fine. Took my 14 ft Gregor with 3 smaller people at 24 mph. When I come back to idle, it will eventually die. At idle, it will begin coughing and drain the carb til it dies. Pumping the primer bulb definitely keeps it running for a little bit, but I cannot keep it running long enough to ensure I have the right low speed mixture.
Background:
When I first picked up the motor, I checked for spark, which seemed weak. It also appears that the electric starter it came with was aftermarket as these did not come with electric start. Serial No. 18103s…. It was also missing the fuel pump which right now I realize is a big red flag of what the PO was dealing with. I did a compression test and I think it was around 110 each. All I know is that it was close to even. It is also pretty tough to pull start it. The gearcase was toast and filled with mud. Thanks to Facebook I was able to locate someone with the parts for a good deal. Has forward and reverse now! New impeller, but the telltale seems hot compared to my other motors even with the new one installed.
What I’ve done:
I installed an ignition kit. Now it shows no ignition issues. I installed a carb kit. The carb initially did not look too bad. But it leaked around the original gasket. I bought a $10 fuel pump off eBay. That’s when I noticed the the idle problem. I then found out that my fuel pump was upside down. I flipped it over and it helped get to full throttle quicker, but carb still drains at idle. I bit the bullet and payed $110 at my local marine store on the omc fuel pump thinking the $10 one was no good. No difference. I was told that my top crankshaft seal is likely gone and causes low fuel pump pressure. I performed a soap test as directed. One with plugs installed and one without. I could not see and signs or bubbles as I was turning the crankshaft. Maybe it’s a very slow leak that could be causing this? I placed my fuel tank on a ladder with the cap open and tried a different primer bulb. My tank and lines seem good since my 1980 Sea King 15 shows fuel issues with the same setup.
Background:
When I first picked up the motor, I checked for spark, which seemed weak. It also appears that the electric starter it came with was aftermarket as these did not come with electric start. Serial No. 18103s…. It was also missing the fuel pump which right now I realize is a big red flag of what the PO was dealing with. I did a compression test and I think it was around 110 each. All I know is that it was close to even. It is also pretty tough to pull start it. The gearcase was toast and filled with mud. Thanks to Facebook I was able to locate someone with the parts for a good deal. Has forward and reverse now! New impeller, but the telltale seems hot compared to my other motors even with the new one installed.
What I’ve done:
I installed an ignition kit. Now it shows no ignition issues. I installed a carb kit. The carb initially did not look too bad. But it leaked around the original gasket. I bought a $10 fuel pump off eBay. That’s when I noticed the the idle problem. I then found out that my fuel pump was upside down. I flipped it over and it helped get to full throttle quicker, but carb still drains at idle. I bit the bullet and payed $110 at my local marine store on the omc fuel pump thinking the $10 one was no good. No difference. I was told that my top crankshaft seal is likely gone and causes low fuel pump pressure. I performed a soap test as directed. One with plugs installed and one without. I could not see and signs or bubbles as I was turning the crankshaft. Maybe it’s a very slow leak that could be causing this? I placed my fuel tank on a ladder with the cap open and tried a different primer bulb. My tank and lines seem good since my 1980 Sea King 15 shows fuel issues with the same setup.