'99 Honda 25hp hiccups at high speed

[Heartman]

My engine starts good, idles good, does just about everything good except that it kind of hiccups while running WOT. Doesn't slow down when WO, just hiccups several times a minute - maybe every 15-20 seconds or so. I kind of think it might be running a bit rich - loading up? Plugs have not shown anything out of the ordinary, but plan to replace soon. Fuel pump? Looking for help here.

Any advice on this issue? Are there carb settings I can go back to and adjust as needed - do not have owner's manual for this engine.

[redhooks]

I'm not much of a mechanic but, assuming the motor is a 4 stroke, the fuel mix should be automatic.

Is the fuel bulb hard when motoring? if not maybe a fuel flow issue-fuel filter clogged?

I did a quick search online and found a couple ideas.

1. High speed jet plugged on carb? clean and resync.

2. Rev limiter if you have too high RPM?

Seloc and Clymers sell repar manuals for your model, might be a worthy purchase. Good luck,

redhooks

[marine_man]

Could be water in your gas too. How new / old is your gas?

It sounds like that or something floating around in the bowl, clogging the high speed jet from time to time.

marine_man

[Outfitter17]

I think marine man it write, I have a few 25 hondas and every once in a while we need to clean out a bowl. They will get a little sediment in them at times and will act just like you described.

Dump the bowl and report back.