BF200 gas in oil

[surfer_mlt]

I have a 2005 BF200 with just under 300 hours that has sat for the last 6 years. HP fuel was froze up when I got it. Replaced the HP fuel pump, HP and LP filters, the HP pump holder that has the screen below the pump, and cleaned the screen in the fuel rail and behind the idle speed module. Also put in new plugs. After doing this the motor ran good on ear muffs. Checked oil during initial troubleshooting and everything looked good.

Took to the water for a test and the wasn’t pumping water. Took home and replaced the water pump, thermostats and orings, and flushed the water jackets.

Ran motor in a tank and wouldn’t idle and ran very rich. After pulling the vst several times and chasing my tail I found almost 4 gallons of fuel/oil during the oil change. Replaced with clean oil and ran again. Motor smoothed out and ran great for about 10 minutes before it started to bog down again. Crankcase is full of fuel again. Only code I’m showing is for the O2 sensor.

It’s too much fuel to be from blow by from the rings and the motor ran great for about 10 minutes before it started to bog and not idle. What would cause this? I’m suspecting a cracked diaphragm in the low pressure pump but won’t be able to look at it again for about a week and figured I could ask the gurus where to go from here. Something is dumping a ton of fuel in the crankcase very quickly and I have no idea where to go from here.

Ps this forum has been a treasure trove for guys like me who are new to Honda outboards. Thank you for any help.

 

[jgmo]

Well, I would say your lp fuel pump guess is certainly a good one and a bad fuel pressure regulator that is stuck high or has a ruptured diaphragm might contribute to something like this too.

But, I think that it's very possible that you could have one or more fuel injectors dumping fuel or stuck partially open. It's something to consider anyway.

Those long layups take their toll on things. If any water or ethanol was sitting in the fuel rail, I'm just not sure how much damage that would cause.

The injectors might be successfully cleaned if you can locate a reliable place to send them in for service and replacement is always an option.

Good luck.

 

[chawk_man]

Yes, I agree with Jimmy on this - likely the LP fuel pump. That's the only thing I can think of that would dump that much gas into the oil. Stuck injectors would likely blow most of the raw fuel out the exhaust. A bad HO2 sensor will only cause the engine to run rich but I see no way that would put that much fuel in the oil.

One other thing - after sitting up that long it would not be unusual for your rings not having a good seal. You may want to run a heavy dose of Yamaha Lube Ring Free (2 ounces per gallon) through the engine using an auxiliary tank. Thereafter, whenever you fuel up add Ring Free at 1 ounce per gallon. That will serve as both a maintenance cleaner and stabilizer.

Over the years I developed a detailed maintenance schedule for my BF 225, which I will attach. This should be useful. Each item shows any needed part numbers (for my 2007 model) and reference to the relevant section in the Helm Shop Manual.