Both engines keep quitting is it the fuel?

[Philip Stone]

Just returned from a bit of a marine moment, luckily the conditions today were fine but it is winter and we've had a fatal boat sinking this week so tensions are running high.

I have a 2005 Honda BF50 and a older (1997) Honda 8 four stroke. Today I ran out into the strait and pulled and set prawn traps. All seemed fine - beautiful day actually with snow on the mountains and right down to the high tide line. But on the way back to the dock the 50 started to rev down like it was running out of fuel, I was surprised as I thought there was plenty of fuel. Switched tanks and it revved up briefly but then started to behave as it was fuel starved. Then it quit, I restarted two or three times before it refused to start again (6 -7 tries didn't want to run battery down).

I dropped the 8 hp into the water and started it. Amazingly it did fire up after sitting idle for 4 months. But then the same thing happened. I could pump the bulb and get fuel in it and it would start, run for a minute or two and I steadily limped toward the dock. The last time it quit that was it about half a mile out.

Luckily I flagged down a passing boat and got a tow to port.

Where do I start? I don't suspect the engines as they were only just serviced and have been running fine - plus the coincidental behaviour seems to point to the fuel - I had topped up each 5 gallon tank before leaving from a jerry can I had sitting in my car port for 3 months. One tank was more than half full already and had been running fine on that. It ran fine on the way out (20-30 minutes).

There is a fuel separator.

Any suggestions what to do?

 

[kandil]

Re: Both engines keep quitting is it the fuel?

it sound like the vent is clogged maybe some water got in the vent and froze!!glade you made it back

 

[Philip Stone]

Re: Both engines keep quitting is it the fuel?

it sound like the vent is clogged maybe some water got in the vent and froze!!glade you made it back

Do you mean the fuel tank vents? I did open the fill caps on both tanks and they weren't depressurized at all. It has been quite cold (-15 C) in the past week but warmed up to barely freezing yesterday.

 

[zzzzz]

Re: Both engines keep quitting is it the fuel?

empty the separator filter into a clear container and inspect the fuel...do you have ethanol fuel up there ? if so it ages very quickly...lasts 90 days or less...new rule for ethanol-use it up and buy fresh(every 2 weeks)

 

[gss036]

Re: Both engines keep quitting is it the fuel?

Sounds like a water issue to me also, check your filters as ZZZZZZZZ says. You didn't say but I am presuming you run both motors off of the same tank. You said you opened the tank and it wasn't pressurized, did you leave the cap loose and try to run that way?

 

[Philip Stone]

Re: Both engines keep quitting is it the fuel?

Here's the update: I emptied one of the fuel tanks into a bucket. No significant water - less than half a teaspoon of oily guck and a few bits but that's it. Drained the fuel separator and there was a little (1 oz) of water which didn't look much more than the separator doing its job.

I disconnected the fuel line from the 50 hp and held the little ball valve open while I pumped the fuel line bulb. No fuel. I squeezed the bulb repeatedly but it never showed any fuel with the ball valve open or closed and the bulb never felt like it had was filling either.

So I'm suspecting a fuel line blockage - does that sound right? Do the separators deteriorate or expire? This one is four years old ~500 hours.

 

[kandil]

Re: Both engines keep quitting is it the fuel?

I would get a 3 gallon tank and test with it and use it after that for the kicker

 

[cousinabe]

Re: Both engines keep quitting is it the fuel?

Filter every season or 100 hours, whatever comes first. If she starts acting up on you, the first thing I would do is change the filter no matter if 100 or 1/2 hour of use. Reason being you NEVER know what kind of crap you just loaded in your tank at the gas station.

 

[Lone Duck]

Re: Both engines keep quitting is it the fuel?

could the anti siphon valve be freezing? Or the valve in the bulb?

 

[gss036]

Re: Both engines keep quitting is it the fuel?

The primer bulb will not pump anything unless it is held in a vertical position because of the internal check valve. Once fuel flows it will siphon by gravity if you put the line down and into a container.

 

[pvanv]

Re: Both engines keep quitting is it the fuel?

Sure sounds like a fuel issue.

If no fuel comes out when the motor-side check valve is held open while you squeeze the primer bulb, you're either getting air (a leak on the suction side). or not moving fuel (blocked line -- anti-siphon valve, or whatever). Of course, as the bulbs age a little, they don't work well unless the OUT side is up, and the bulb is vertical, as the check valves do get lazy. If the suction side is blocked for some reason, and the bulb is working correctly, the bulb will likely collapse under suction and stay that way. I have also seen that happen as a motor draws against too steep a suction.

Yes, if you find any water at all in the separator cartridge, it would be good to change it out.

I would re-check the fuel line and setup. Sounds like that may be the issue. Since the motors should have decent pumps, once they are running, they should continue to draw from the tank. Unless of course they are drawing air through a slight leak...

 

[Silvertip]

Re: Both engines keep quitting is it the fuel?

I take it these are portable tanks? If so, drain them and then using a pen light, carefully examine the interior of the tank for bits of plastic debris from the manufacturing operation. These can clog the fuel pickup tube, actually puncturing the screen and making their way into the fuel bulb. This happened on two of my after market fuel tanks and I've seen it on many others. I have a habit of checking these brand new tanks in stores and many of those also have debris in them. If you have the check ball open on the fuel line, squeezing the primer bulb should expell fuel. Hold the bulb vertically when doing this. They work better that way. The fuel pickup tube may have broken off as well so examine the tank carefully.

Also disregard the statement about E10 fuel going bad in three months. That is hogwash. Here in the midwest our boats sit from November to April with E10 in them and the engines run just fine in the spring. But then we learned over 10 years ago to use fuel stailizer like SeaFoam or Stabil.