Yamaha 25 4 stroke running issues - The Hull Truth

carofloridakid · 07-30-2009, 07:33 AM

Hey guys. Im new here as you can probably see. I recently inherited a 16 foot skiff with a yamaha 25 on it.

Now heres the issue i have. When the motor is put to WOT, it falls on its face and just stumbles like crazy. Here's the tricky part. When I hit the trim button on my controls, the problem goes away and the motor runs smooth. As soon as I let it go, it stumbles again, every once and a while it will smooth out by itself for a couple seconds and then stumble again. It almost sounds like its not getting enough fuel, but I know it is something electrical. It will smooth out when I hit the trim up or down. Any ideas? Thank you!

A1 Outboard · 08-03-2009, 04:05 PM

Many electrical problems are caused by connections that are loose or corroded. Check all your wiring including the grounds. Tighten loose connections and clean off all corrosion.