Motor Problem…please help…

I bought a used boat w/ a 1999 25hp Honda 4 Stroke. First the there was a problem w/ the handle slipping, so it would open up enough to even get on plane. So after 12 or so frustrating hours on the water, that problem is now fixed.

But now, it still doesnt want to open up. After running wide open (at what felt like only 7hp), without turning the trottle or doing anything different, it finally took off and ran at full speed. The rest of the night, when I took off it would take about 1/4 mile before finally getting to full speed.

It feels like it is either starved for gas on the take off or the carbs arent opening. It runs perfect at idle, trolling and low speed. It starts up right away and idles fine cold.

Any ideas??? The fuel line is extra long-but looks new.

Signed-frustrated on Pool 2

Sounds like your power pack is going. Meaning you are losing spark to a cylinder intermittently.

It will only get worse. Take it back to the dealer and have a new one installed. (Hope they will cover that since you just bought the rig) If not, a new one will cost $200-250.

Dino just went through the same deal on his motor.

Jon J.

Will that happen on a 4 year old motor???? The engine is still spotless.

Hope it is! Would be an easy fix and not a bigger prob. Have you checked the plugs? Could it be as simple as a fouled plug?

Jon.

Yes-the plugs are all fine. That is about the extent of my troubleshooting skills!

Do you have an in line spark tester? I have a neon type that glows brightly with the proper spark. This would allow an easy check of the cylinders to be sure they are firing properly. Let me know if you would like to use it.
Dino

You say the fuel line is xtra long? It could be kinked somewhere from the tank to the engine.Maybe an anchor is layin on it? If so It would maybe act the way you speak. Another thing is if the vent valve on the tank is closed It would cause this problem. It sounds like you aren’t getting air to the fuel system. Or Maybe its as simple as the fuel filter being dirty? There again if it sat around for a couple years with gas in the tank maybe the OTHER filter IN THE TANK is gunked up.With any luck its one of these, otherwise it sounds like its expensive, from an earlier post.
Trigger

Noticed on my 2001 that there is a recomned fuel line length. Six feet was what I think it said. I got the same motor for my rig just 2 years newer.

If you checked the plugs and they look good,no sense in looking further in the secondary ignition. If the plugs were not firing they would soot up quickly,even if it eventually picked up and ran good at high RPM’s. From what your describing it sounds like your either losing primary ignition (coil pack) or most likely fuel delivery. Be sure you have the correct length fuel line and that the primer bulb isn’t deteriorated. Once thats ok check the fuel filters,should be one in-line to the power head and one in the fuel cell at the pick up point. Replace the in-line one for maintenance anyways. You can disconnect the fuel line and blow backwards into the fuel cell with your mouth (don’t swallow any gas) to see if there is a restriction. Remember you can’t blow through the bulb. If that checks out go on to be sure the fuel cell vent isn’t restricted. The fuel cell won’t expell fuel in sudden surges (acceleration) if it can’t replace the expelled fuel with air. Kinda like dumping gas out of your can with the little vent cap on. Those are about the extent of the basics you’ll be able to cover without either a service manual or a test tank and dyno prop. Good luck!