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Honda BF50 D cranks but no start

H

har

New member
My 4 cycle BF 50 D ( previously jast broken in) has not been
used for 2 years .I tried to start it up recently. It cranks,
but will not start at all.I have sparks on the 3 plugs, the
Prime bulb works, the filter is clean and the low pressure
fuel pump is clean and its piston moves freely.
I checked the injectors being OK.
I checked the fuses and they were OK but the lowest position
30A fuse had a lot of yellowish oilish substance behind it.
I have no idea where this came from.The whole motor
is spotless clean with not even a drop of oil anywhere.
I cleaned it out and are still mindbuggeld.My boat is above the
water and not at home and I wonder what to check next.
My repair manual did not help to much yet .
Can anyone give me some help please.
 
When I suspect an engine to have a fuel delivery problem I prove it by putting propane gas directly into the air intake. If all else is good the engine will start and run. This can be accomplished by using a plumbers torch with a piece of rubber hose connected to the pipe in place of the burner/mixer nozzle.

As Alan asked, can you hear the high pressure fuel pump run briefly when the key is cycled on?
Two years of sitting has probably not been great for the fuel system.
 
Hi Alan,
I rigged a hose to fit the injectors and my compressor dispenser ,filled in some carb.cleaner and attached it using 2 hose clamps. I used a 12 v De Walt battery and shortly triggered
the contacts to clean/ and spray a pattern. The injectors clicked and sprayed a good pattern.
I could not hear the HP fuel pump run for 2 sec because of the distance between the side mount control and the motor. I have some slight hearing impairment.
The control came on with 2 beeps like usual. I will check on this next time.
Thank you both Alan and jgmo for your suggestions.
 
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I checked today : by turning the key I heart the typical 2
beeps but no sound from a running fuel pump
I assume the fuel pump is fouled up and I have to take out
the vapor separator assembly to get to it. Do I have to take out
the manifold etc.to get the vapor separator out. Please
advice.
 
Just for grins, pull your kill switch yoke and exercise the kill switch a bunch of times then reconnect the yoke and try to start. Alternatively, disconnect the kill switch wires. It is not unusual for corrosion to bridge the contacts in the kill switch. I've not had this problem with a Honda kill switch, but the old Johnsons and Evinrudes were notorious for this.
 
It is easier to remove the intake manifold but you can get it out without doing that. Just be aware you will need a new fuel pump and after market pumps do not work on those motors, so don't waste your money on one, just get genuine y
 
iang6766 said:
It is easier to remove the intake manifold but you can get it out without doing that. Just be aware you will need a new fuel pump and after market pumps do not work on those motors, so don't waste your money on one, just get genuine y
Click to expand...

Why would he need a new fuel pump? You mean IF he needs a new fuel pump?

I would pull the intake. It's much easier.

Too, when reinstalling the fuel pump, there's a grommet that holds the top of it in place. It MUST be installed on the fuel pump, then inserted into the top of the vapor separator. If you install the grommet into the top of the vapor separator first, then install the pump, the grommet will very likely deform, blocking fuel flow from the pump. Huge headache as many of us have learned the hard way.
 
Why would he need a new pump???? Because it doesn't work and once they have failed you can't resusitate them, the varnish build up from the stale fuel kills them
 
I've taken a few of them apart, and with one in particular, found that found it wasn't getting power for instance. Suit yourself, but here, they aren't dead until I prove they are...... that's me though... -Al
 
Allan, I am just speaking from personal experience, those pumps will not survive two years of no use sitting in stale fuel, it is the single most common cause of failure. I am not trying to create an argument here, just offering help to those who ask for it.
 
In all likelihood, you've worked on more of them than I have. I just hate making assumptions regarding decisions like that.

Not meant to be taken personally. Possibly I just have a different perspective. I do this as a hobby, and am willing to take the time and trouble to prove a failure. If I were doing this for a living, there's a good chance I would want a pump there on the bench prior to even taking the vapor separator apart.

Thinking maybe we are both here for the same reasons.... -Al
 
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