2000 150 V-max won't rev up with WOT

[Robster]

Took my boys out today, and my 2000 150hp Vmax cranked fine, idled fine, but when I got outside the no wake zone, went to WOT and got next to no response. Wouldn't rev up, not even close to planing. Maybe 2000 rpm tops. Felt like I was dragging an anchor (hehehe, and yes, I checked that!).

I did notice when I was pumping the bulb before cranking, it would get firm, then another pump later it'd be slack again, so I'd pump a few more, get firm then would slack again. Guessing it's a fuel line issue? Open to any ideas before I drag her down to the mechanic.

[21XDC]

Check for low oil... There is a 2000 rpm safety for this.

[Robster]

Oil tank is topped off, and got no alarms either. I will check the tank on the engine, though, but I am certain the main tank is totally full. Thanks for the input.

[dward51]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by Robster &raquo;</td></tr><tr><td class="quote">Oil tank is topped off, and got no alarms either. I will check the tank on the engine, though, but I am certain the main tank is totally full. Thanks for the input.

</td></tr></table>
The on engine tank is where the sensor is and if this one is low it will go into limp home mode (low rpm). But you should be getting an oil alarm also.

[Robster]

It sure acted like it was in limp home rev-limited mode, that's for sure. RPMs would advance with throttle slowly applied fine, but once it got past about one-third throttle, it gave me nuttin'.

[Robster]

Checked the tank on the engine, and it's full, and the main reservoir is also full. I guess I'll just have to drag her down to the shop this week. Don't know what else to do.

[dcbassman]

have you changed your plugs recently? Check and make sure all of the plug wires are pushed in.

[Robster]

Had to have the prop shaft pulled and straightened, but the mechanic said it straightened fine and installed with no problems, and the prop spins true. Only other recent work done was a new water pump, and it was peeing fine the whole time.

But that makes me wonder if maybe something in the overheat sensor maybe is screwy, since doesn't the rev limiter kick in when it senses overheating? Could the new water pump somehow be causing this and not the low oil sensing system, since the oil reservoirs are all full, and there's no alarms?

[Robster]

Turns out it was 2 fouled plugs, according to the Yamaha tech. Simple -- looks like I over-thunk this one maybe?