Hello,
I have a 2003 Mercrusier 5.0 with a 2 bbl carb with an electric fuel pump. The last few times out it’s been difficult to start after running. Cold start it fires up after a few cranks. I’ll run it around the lake for about 45 minutes without an issue and then anchor in a cove and swim for a few hours. After a few hours sitting it will start and run for about 30 seconds before it dies. I assume it’s burning the remaining fuel in the bowl. Typically after cranking it a few more times after it dies it will start and have no issues. Today we ran the boat for about an hour and swam for two. Started the engine and it started but after about 30 seconds it died. I tried cranking the starter for about 20 seconds, waiting a minute and repeat with nothing. Took the flame arrester off and pumped the throttle but it was bone dry - nothing coming out of the accelerator pumps. Cranked the engine over again while pumping the throttle and nothing. Then I took the fuel line off the carburetor from the electric fuel pump and cranked - no fuel coming from the line. I thought maybe the fuel pump failed so I spliced the wire and ran a hot lead to the battery. The pump kicked on but still no fuel from the line. At this point I thought maybe the filter was clogged (just replaced a month ago) or the fuel vent was clogged. I opened the fuel cap and ran the pump off the hot wire. About after a minute of running fuel started to flow out of the line. Hooked the line up and took my hot wire off, started the boat and it ran for about 30 seconds and died. Tried cranking and nothing. Hooked the hot wire back up, fired the boat up and limped back to the dock with the hot wire attached. Now safe at the dock I unhooked the hot lead to the fuel pump and let it run for 10 minutes on its normal circuit without a problem. I will add the fuel cap was off for all of this. My thoughts are maybe a clogged fuel vent or some other electrical issue. What are your thoughts and where should I start troubleshooting? Not sure why it runs fine for over an hour under power but has this issue after sitting in a cove while hot. I would think if the vent was clogged it would has some effect during cruise. Maybe the oil pressure switch? Something else?
Thanks for the help!
I have a 2003 Mercrusier 5.0 with a 2 bbl carb with an electric fuel pump. The last few times out it’s been difficult to start after running. Cold start it fires up after a few cranks. I’ll run it around the lake for about 45 minutes without an issue and then anchor in a cove and swim for a few hours. After a few hours sitting it will start and run for about 30 seconds before it dies. I assume it’s burning the remaining fuel in the bowl. Typically after cranking it a few more times after it dies it will start and have no issues. Today we ran the boat for about an hour and swam for two. Started the engine and it started but after about 30 seconds it died. I tried cranking the starter for about 20 seconds, waiting a minute and repeat with nothing. Took the flame arrester off and pumped the throttle but it was bone dry - nothing coming out of the accelerator pumps. Cranked the engine over again while pumping the throttle and nothing. Then I took the fuel line off the carburetor from the electric fuel pump and cranked - no fuel coming from the line. I thought maybe the fuel pump failed so I spliced the wire and ran a hot lead to the battery. The pump kicked on but still no fuel from the line. At this point I thought maybe the filter was clogged (just replaced a month ago) or the fuel vent was clogged. I opened the fuel cap and ran the pump off the hot wire. About after a minute of running fuel started to flow out of the line. Hooked the line up and took my hot wire off, started the boat and it ran for about 30 seconds and died. Tried cranking and nothing. Hooked the hot wire back up, fired the boat up and limped back to the dock with the hot wire attached. Now safe at the dock I unhooked the hot lead to the fuel pump and let it run for 10 minutes on its normal circuit without a problem. I will add the fuel cap was off for all of this. My thoughts are maybe a clogged fuel vent or some other electrical issue. What are your thoughts and where should I start troubleshooting? Not sure why it runs fine for over an hour under power but has this issue after sitting in a cove while hot. I would think if the vent was clogged it would has some effect during cruise. Maybe the oil pressure switch? Something else?
Thanks for the help!