CONTINUOUSWAVE

Hello CW. I have a Honda BF130 that is giving running problems. After engine start and running at low to moderate speeds, and even about three-quarter throttle the HONDA BF130 engine runs great.

But after about two hours of running the HONDA BF130 engine, and almost ALWAYS after a full throttle run, the engine immediately starts misfiring and surging. The misfire and surging will not go away at all under any conditions.

At idle the HONDA BF130 misfires and the boat shakes.

When the throttle is advanced the engine accelerates slightly, but the engine hesitates. The engine runs like it wants to die. The throttle must be reduced as if the engine were bogging. The HONDA BF130 engine will continue to idle and will run at low RPM while misfiring.

After the HONDA BF130 engine exhibited the misfire, surging, and bogging the first time, new spark plugs iwere installed. The result was the misfire, surging, and bogging never happened when the engine was being run on a hose adapter. The problem did not occur on the water this week until it did it again same exact timing and situation.

I recently have:
*Changed the plugs (concern now back so ordered another set)
*Changed the oil
*Changed the fuel filter
*Completely emptied tank and put brand new premium in it
*Checked thermostat to make sure it was opening and not stuck
*Changed the water pump at the end of last season, stream is fine (about new hours on pump)

After the spark plugs were changed the first time the HONDA BF130 engine started instantly and there was no misfires, surging, or bogging.

Second set of spark plugs is on order. I want to see if a second set of spark plugs may fix the misfires, surging, and bogging.

I think the cause of the misfires, surging, and bogging may be poor fuel quality.

To watch a motion picture with sound when the engine has misfires, surging, andbogging, go to
https://www.youtube.com/watch?v=IP2D6jXGhmw

Consider a carburetor cleaning or overhaul.

Tell us what the plugs look like when you remove them, might explain a lot. Does it only do this when warmed up or does it continue to misfire the next day?

I have this outboard on my Outrage, I’d recommend you get the Honda shop manual, available from Honda dealers or from Honda on eBay and maybe Amazon. Don’t bother with a Clymer.

As requested, post pics of the plugs you removed, if new plugs made a difference, the old ones must have been fouled. Figuring out why will be the way to fix this.

Have you had any alarms or check engine lights come on , which ones?

Was there any debris in your fuel filters?
There are numerous possibilities for your problem and my first guess is electrical, something like spark plug wires or a coil, but that is just a major shot in the dark.

I’d also try running some sea foam through [the fuel system] or whatever [fuel system] cleaner you prefer.

Hook up a portable tank to your fuel line; it will take a lot of cleaner if you put the cleaner in your fuel tank in the boat.

Are you using ethanol free fuel?

And Stabilizer in the tank?

Use fuel additive products endorsed by the engine manufacturer for your outboard engine. Don’t risk damage to a $15,000 engine from a $5 fuel elixir formulated for 1950 automobile engines.

Gasoline itself is a very good solvent. Dosing gasoline with even more harsh solvents could be ill advised. Modern day fuel systems contain plastic and rubber components; they may not tolerate certain solvent additives.

Be methodical. Change one thing at time, Test, then change another, test. etc. Document results.

Make a list and follow it.

Don't assume anything. Proof is required.

Start with the fuel tank and fuel line. Easy to do.

Manufacturers today recommend you have a dealer change your oil and filter, and in automobiles, change your lightbulbs. Those things I am capable of doing, I choose to do myself, in spite of what manufacturers say. This saves me time and money.

I have used SeaFoam fuel additive for about ten years with good results to clean injectors, valves, and carburetors. In a fuel injected engine like this 2001 Honda BF130, which is the same outboard I own, SeaFoam works fine. SeaFoam helps the engine run better when needed. Most engined I use SeaFoam with have ethanol-resistant gaskets and rubber. and SeaFoam does not harm these gaskets and rubbers

The [HONDA BF130 engine under discussion] might have a [spark] coil going bad. I recently had a similar problem with my [engine].

Visit Harbor [Freight], get [a] $4 [in-line] spark [gap] tester, and check [each cylinder for spark].