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Honda BF200A Running Rich and Hot

M

mydogcoach

New member
Hi everyone this is an update from last weeks post about my Honda BF200a outboard motor shutting down as soon as it getts throttle. Today we changed the Fuel Pressure Regulator and the motor seamed to respond a little. We where able to slowly increase the throttle and motor stayed running however not not great. It sounded like it was not running on all 6 cylinders. We systematically removed the wires from each coil pack and all seamed to change the sound of the motor. When we first started the motor after the regulator replacement it ran ruff and shut down when we added throttle. We then started the motor with full throttle and it started to run but very ruff. We went back to starting in neutral and were able to added a little gas at a time in small increments the motor seamed to respond ok sounding better but not great. We actually got to full throttle but notices a lot of gray smoke from exhaust and still wasn't running on all cylinders at this point it back fired. After about 1/2 hr of letting it run(poorly)we were still able to start it but it was running rich and the motor was hot. The ports stopped pumping water so we shut it down and are getting a new water pump/impeller before we start it again. We plan on checking compression tomorrow. One of the guys helping me thought the coil packs weren't working properly and wants to check the ohms does anyone know what the readings should be? Could the MAP sensor be causing this?
thanks
 
1st. Read the plugs.
2nd. Confirm fuel pressure is correct.
3rd. Confirm all filters and screens are clean.
4th. Get injectors cleaned and checked.

This should remove fuel delivery as a culprit. Most problems are fuel delivery.
 
you need to run Dr h and check all sensor parameters, map can cause this but would usually set an alarm. Stick to basics first, check compressions .It's highly unlikely that more than one coil pack would fail, check cam timing as per manual, it takes about 5 mins.
 
Hi Everyone, So Today we did a compression and spark test both came back good. We then did a Fuel test on the High Pressure fuel filter port. It came back at 13 PSI. I Think this means the High pressure fuel pump is not working properly I believe its supposed to be between 41-49 PSI. Would this cause the motor to run rich or out of timing if the fuel pump was not working properly?
 
In your original post, Ian and I both took you through some basic diagnostics to try. Have you done all of those? Especially check the timing as Ian described.

What were the compression numbers?

Did you check the vacuum hose to the fuel pressure regulator for cracks or leaks?

If you got 13 psi fuel pressure, AND the the HP fuel filter has been changed, AND the screen on the bottom of the fuel pump insulator has been cleaned, then you MAY have a problem with the fuel pump itself. However, it has been my experience that in general fuel pumps either run correctly, or fail completely, and that is not the case here. Make sure you are getting 12 volts DC to the pump at the plug. Hook up a voltmeter to plug going to the fuel pump and have someone turn on the key switch. You should read battery voltage for about 2 seconds. If so, make sure you are getting 12 volts on the end of the harness where it plugs into the pump itself. Also, check that the black wire to the fuel pump plug has low resistance to the engine ground. Finally, disconnect the return hose from the pressure regulator and hook up another hose that you can feed into a jar. Turn on the fuel pump for about 2 seconds and measure the amount of fuel you get. It should be at or above 2 ounces.

Something else to check is the fuel line cutoff solenoid - Make sure the hoses in and out are totally clear, unplug it and test resistance. It should be between 43.2 and 52.8 ohms. If not. Replace it.
 
We have changed the LP filter, HP filter, Insulator(which we were told was the original problem we had 586 hrs on it and it had never been replaced), spark plugs, Fuel filter regulator and cleaned air filters. Check compression which all were between 187 and 200. Check spark all had spark. We checked all vacuum hoses. no gas leaks, check screen in tank. Only thing we have found is 13 PSI on HP pressure fuel port. not sure about Fuel line cut off. accept for the reduced speed and RPM that we experience last year all problems seamed to come after we replaced the Insulator on the VST. We have been back in that unit one other time and replaced all O rings and no change happened.
 
This may sound like a stupid question, but one of my guys did it, have you installed the high pressure filter the right way round, if it is incorrect it will partially block the fuel flow?
 
I am also puzzled as to how it can run rich if there is such low fuel pressure, are you checking the fuel pressure correctly?
 
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