Yamaha 200 Drops Power: Is a Loose Throttle Friction Setting the Cause?
I have a 2024 Tidester with a 200 HP Yamaha outboard. The boat keeps dropping power underway. It takes almost no effort for the lever to drop back to neutral, but I have to push it substantially further forward than normal to gain power. Could the actual throttle handle just be falling back?
Answer
Yes, a loose friction setting on the throttle binnacle causes the handle to vibrate back towards neutral, instantly dropping your engine revs. You can fix this in two minutes by tightening the friction adjustment screw located on the front or base of the control box.
Adjusting the Friction Screw
Marine throttles feature an adjustable friction brake to counteract engine and hull vibration. When this brake backs off, the weight of the handle and the movement of the boat pull the lever backwards. The handle dropping back without effort points directly to a slack friction screw.
The adjustment method depends on your specific 2024 Yamaha 200 HP control box.
- Yamaha 704 Top-Mount: Look at the forward-facing lower section of the binnacle. You will see a small black rubber plug. Pry this out with a fingernail or small screwdriver. Inside sits a flathead screw. Turn it clockwise to increase friction.
- Yamaha 6X9 or 6X6 DEC: Electronic controls feature a mechanical friction screw to give the lever a realistic feel. You will find this on the front face of the base. It requires a Phillips screwdriver.
Make adjustments a quarter-turn at a time. The lever must hold its position at cruising speed without requiring you to wrestle it when docking.
Fixing Sloppy Throttle Travel
Excessive forward movement of the lever before the engine gains power indicates slack in the control cables. The handle moves, but it only takes up dead space before pulling the throttle linkage on the engine.
Adjust the trunnion at the engine end of the throttle cable to resolve this.
- Remove the engine cowling and locate the shift and throttle linkages on the starboard side of the block.
- Ask an assistant to move the throttle lever forward and back so you can identify the throttle cable. This cable moves the throttle cam, not the gear selector.
- Pop the throttle cable end off the linkage pin. You will see a threaded barrel (trunnion) secured by a 10mm lock nut.
- Wind the trunnion down the threads to remove the slack, ensuring the throttle cam rests perfectly against the idle stop when the binnacle is in neutral.
- Reattach the cable and verify that pushing the binnacle to wide-open throttle physically pushes the engine linkage to its maximum stop.