Merc 496HO EFI / Rhinda Question
09-05-2025 | 05:12 AM
#12
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For an outboard that is hard to start and idles poorly, the most common culprit is a dirty or clogged carburetor, especially on new-to-you boats. The idle jets are particularly susceptible to clogging from fuel residue, especially if the boat has been sitting for a while.
09-05-2025 | 09:17 AM
#13
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From: South FL
these are MPI 496HOs not outboards
FWIW - Fuel delivery has been a challenge as 4 75 gallon tanks are literally 37 years old and have internal baffles so hard to get all the crap sucked out. Been doing the racor water separator before the standard on engine fuel filter and change them EVERY 2 tank fills or every 600 gallons. Been going well lately.
I suspect crap in Injectors or bad IAC but will do plugs and oil this weekend....test each plug for spark with in-line spark light thingy and if still having some fuel sheen in the water at idle will do IAC and consider doing injector cleaning next.
FWIW - Fuel delivery has been a challenge as 4 75 gallon tanks are literally 37 years old and have internal baffles so hard to get all the crap sucked out. Been doing the racor water separator before the standard on engine fuel filter and change them EVERY 2 tank fills or every 600 gallons. Been going well lately.
I suspect crap in Injectors or bad IAC but will do plugs and oil this weekend....test each plug for spark with in-line spark light thingy and if still having some fuel sheen in the water at idle will do IAC and consider doing injector cleaning next.
