2007 4.3 MPI mercruiser starting issues / fuel issues

[shackle101]

Hey guys so I'm having issues with my 4.3 mercruiser starting, and running smooth when adjusted into low RPM. Once you do get it started it will run fine at high RPMs, but if you go down on the throttle it will turn the engine off.

I know there was some old gas in it I ran on so I replaced the Fuel filter with a brand new one. Now it's having issues even starting. When I filled the fuel filter up it started and ran fine for awhile, but had issues again after a few mins. I checked all the fuses and nothing is busted. The fuel pump seems to be running fine, and the hoses going into the filter seem to have gas in them when I unplug them.

Any ideas here?

Thanks!

 

[Fun Times]

When I filled the fuel filter up it started and ran fine for awhile, but had issues again after a few mins.

With the quote mentioned above, Try rechecking the fuel filter to see if it's still full or low on fuel again.

Be sure the fuel tank vent is not clogged up from sitting over the winter. You could try opening up the fuel filler cap on the boat to use as secondary vent as a test. Is there an inline filter between the fuel tank and water separating screw on fuel filter?

If all that test good then maybe you have a low fuel pressure situation and you'll need to get a fuel pressure gauge to see what the pressure really is.

Or maybe you have an idle air control (IAC) problem or need to clean the throttle body and install a new IAC muffler item number 6, http://www.mercruiserparts.com/Show...82.png&inbr=13808&bnbr=80&bdesc=Throttle+Body

May want to clean the flame arrestor too if it hasn't been yet.