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BF115A Honda 115 Four Stroke Stuttering/Cutting Out At High RPM

ToMang07

ToMang07

New member
So got an older (2003) Godfrey Aqua Patio with BF115A on it. Has a little under 500 hours. It idles great, purrs like a kitten, very even and quiet.

When you go high throttle to WOT, (somewhere in 3000-3500 RPM+ range) it'll run great for a minute or 2 then start to cut out like it's running out of fuel.

Most of the time if I cut it back or reduce to idle it recovers and continues to run fine. But pretty much every time I try to go high idle this happens within a minute or 2.

I'm unsure where to start. Weak fuel pump? Bad fuel lines? ECM?
 
Sounds like a fuel restriction is the first thing to check.

What year is this 115? The 1998 to about 2004ish are different technology than later 115’s. The older units usually came with a sticker saying they meet 2006 emissions, that factory sticker is on my 1999.

Check and or change all filters starting at the fuel tank end. Check each filter for dirt as you go.

Also check condition of the rubber fuel lines, they may be old and rotted, allowing an air leak or spitting bits of rubber into the fuel system.

What condition are the plugs? Any fouling? All cleans and fresh?

Have the valves ever been adjusted?

After doing that, there will be electrical issues to check out.

Buy the Honda shop manual for your outboard, don’t bother with the other generic manuals.
 
Hi,
Assuming that you use a portable gas tank, that's where I would start.
Make sure nothing is floating around in the tank and that it is clean.
Check the vent to make sure it's fully open and there's no debris or dirt partially blocking it. Those vents will vibrate closed over time.

Then there's the quick fuel line disconnect. Those can wear over time due to vibration. Check that the pin that opens the valve is in good condition and contacts the ball squarely. If the locking latch doesn't hold the two parts tightly together and in alignment, the valve won't be held fully open.

Your question about the fuel pump makes sense. I would consider checking fuel pressure for this but if you don't have the specification or the tools, that might be difficult. I haven't worked on a 115 so I don't have the service information to share with you.

Have you checked/replaced the fuel filter? If not, that might be something to try. is yours like iem 1 in the link below?

 
It's the factory inboard tank that comes with the boat, vent is on the side just above the fuel door.

I had started the day with a full tank (half was ethanol free 90) treated with Marine Stabil. About half through the day added another 8ish gallons of e93 at the dock. I'm not sure on tank size but according to the interwebs it should be either a 24 or 30 gallon tank.

I have not replaced the filters, however it was supposedly done in the fall by a marina before winterization.

At this point I think I will try to replace the fuel lines to the motor, blow the vent line and check that as well, and replace the filters.

I'm currently trying to find a manual, but I'm having a hard time find one reasonably priced that is definitely for this motor. I don't think the valves are bad/out of spec but I'll check them after I get my hands on a manual.

It honestly runs so well idle-3k RPMs that I do suspect it's a fuel delivery issue. And it's a pretty low hours motor for the year.
 
jgmo said:
Please don't scrimp on the manual!
You're likely to regret that.
The genuine Honda Publications is available here:

Honda Marine | Shop Manuals Publications | Honda Power Products Support Publications

publications.powerequipment.honda.com publications.powerequipment.honda.com

The real deal manual is the only way to spend your cash. 1/2 priced, knockoff manuals just provide 2× the disappointment.


There's also a free poster for the 115A on that site too!

Good luck
Click to expand...
This one is one of the issues I've ran into, the manual they have is for the much newer motor. Most of the ones I've found so far either don't specify the serial numbers covered, or they are for the newer motors. I'm looking at a couple of used ones on ebay, although most there look to be overseas, or $200+.
 
Do you have a fuel water separator spin on filter for the tank? Get one if you don’t. Dump that into a clear plastic bottle and let it settle out, check for dirt.
 
NSDON said:
Do you have a fuel water separator spin on filter for the tank? Get one if you don’t. Dump that into a clear plastic bottle and let it settle out, check for dirt.
Click to expand...
I do not believe so, but I will double check. I'm assuming this is generally an aftermarket add-on?

On edit, like this?

 
And I just remembered there is one available with a clear bottom in the screw on filter, you can see the dirt or water without removing the filter.
 
Well, replaced the fuel line and the water separator filter. She runs like a champ now, although I feel it should have more in her, she tops out at about 22mph, which ain't bad for a 23 year old 'Toon.

Thanks for the help fellas.
 
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