350 MAG Quit on me today
05-19-2012 | 11:46 PM
#1
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From: Clear Lake Shores, TX
350 MAG Quit on me today
I have a 1997 Scarab 29 with twin 350s. not fuel injected.
Running today all was well. Idled out of the marina as usual got about 4 miles down the coast and came off plane and lost the the Port Engine when I went to idle.
I couldnt' get it started and limped back home on the starboard engine.
Once in the marina decided to try to start and the Port motor started and ran rough but smoothed out and seemed to run fine until I put the throttle lever at idle it would try to die on me right away.
Once in the slip I messed around with the ECU's to see if they were the source of the pour running condition but they are all ok.
I could get it started in the slip with a little finessing but When it was running I would have to keep it at 1000 or higher to keep it smooth. Also the RPM's would flucuate on there own....And while it was running I could smell A strong fuel smell like it was running really rich. I also observed the fuel line while it was running and there is air bubbles in the line. Once I put the throttle lever to idle it would stumble and die.
The one thing I did confirm is air bubbles in the yellow fuel line during the entire time it was running.
Could this be a fuel pump failing?
Running today all was well. Idled out of the marina as usual got about 4 miles down the coast and came off plane and lost the the Port Engine when I went to idle.
I couldnt' get it started and limped back home on the starboard engine.
Once in the marina decided to try to start and the Port motor started and ran rough but smoothed out and seemed to run fine until I put the throttle lever at idle it would try to die on me right away.
Once in the slip I messed around with the ECU's to see if they were the source of the pour running condition but they are all ok.
I could get it started in the slip with a little finessing but When it was running I would have to keep it at 1000 or higher to keep it smooth. Also the RPM's would flucuate on there own....And while it was running I could smell A strong fuel smell like it was running really rich. I also observed the fuel line while it was running and there is air bubbles in the line. Once I put the throttle lever to idle it would stumble and die.
The one thing I did confirm is air bubbles in the yellow fuel line during the entire time it was running.
Could this be a fuel pump failing?
05-20-2012 | 09:10 AM
#2
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From: Colonial Beach, VA
Sounds like the fuel pump to me. At the very least, it's a great place to start. If you see fuel in the yellow tube (not the fuel line), that is an indication the diaphragm in the fuel pump is torn or ripped in some way.
05-20-2012 | 12:11 PM
#3
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From: Clear Lake Shores, TX
Yellow Line
What is that Yellow Line for? If fuel shouldn't be in it then Thats probably what my fuel smell is from because fuel is pumping through it with air bubbles when the engine is running.
05-20-2012 | 01:22 PM
#4
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From: Colonial Beach, VA
That yellow line is a tattle-tail line that informs you if your having issues with your fuel pump. It is also handy for keeping your bilge from filling with gas and the boat blowing up. It is connected to the other side of the diaphragm in your fuel pump and to your carb. If the diaphragm ruptures in any way, the gas will go up that line and into your carb instead of into the bilge or all over the motor. This is the #1 reason why you should never substitute an automobile fuel pump for a marine pump on a boat motor.
You have a bad fuel pump.
You have a bad fuel pump.
