I am having trouble with my yamaha getting on plane. Last week I tried to beat a storm and the motor would not run above 5000 RPM. After the storm I took it back out and it would not get passed 2000 RPM and would not get on plane. This happen to me last year and I took it in they said they could not find anything wrong with it. I took it out and it ran fine. It also idles just fine and smooth starts just fine. I am not putting the yamalube in it. I was wondering if that was the problem. If you have had the same problem or have any suggestions please post them thanks.

4-stroke or 2-stroke?

"not putting the yamalube" - it's a problem if you're not putting any oil at all in it. otherwise, changing oils won't solve the problem.

Old fuel? Any debris or water in the tanks?
Fuel line holding pressure?
Fuel tank vent open?

It is a 2 stroke. I checked the fuel filter and the red thing ring was not floating. The mechanic told me if that is floating you have water in the line. I took it out today and same problem I did however get it on plane. I may need to drain the gas or is there an additive you can put in it.

Did you choke it when your were on plane?If it takes off and runs good for a cpl seconds then your carbs are gummed up and you need to blow out the needles with some air.

There is an air stem looking thing on the side of the carbs going into an aluminum block. Is this where I hook up the air nozzle?

That schrader valve is for fogging the engine (to winterize).

How old is this motor and what HP?

No "quick fix" for gummed up carbs. Carb cleaning: remove, disassemble, soak overnight in carb cleaner, blow through all passages with compressed air (or aerosol carb cleaner), reassemble with new carb kits, reinstall, link & sync, reset mixture screws (if equipped). Highly recommend getting a service manual - in fact I wouldn't attempt it without one.

Could be gummed up jets; could be debris from the gas tank blocking a hi-speed jet, could be one or more sticking float valves, or a sunk float.

But do a little troubleshooting before ya throw any money & parts at it:

Compression test.
Spark test.
Check the fuel lines for obstructions or leaks.
Does the fuel line hold pressure?
Is the fuel tank vent clear?
Pump the primer bulb while its acting up. If RPM's improve, then the fuel pump is weak. If the bulb is getting sucked flat, then you've got a restriction upstream of the bulb or the tank vent is blocked.
Is there any kind of debris in the tank, could be blocking the inlet?

There's no additive that can fix bad gas - but seafoam and stabil are two good products that keep it fresh.

Don't run it till you've fixed it, except as needed for troubleshooting - if any cylinders are starved for fuel, they are also not getting any lubrication.

good luck.

I had a similar issue (same motor, HPDI) right after I got my boat. It turned out to be a broken reed (valve?)...

Bad reeds are a bad deal especially if the broke off piece(s) get sucked in to a cylinder.

With a reed problem usually carb(s) will be spitting up gas.

it was bad gas. drained the old put in new and runs fine

thanks for everybodys help

BE SURE AND USE RING FREE! Yamaha recommends it in every fill up. I use it each time I add gas. It de-carbons the pistons and keeps the fuel FRESH.

I have a 200 VMAX and it runs like a champ, or should I say, like a Yamaha!

RING FREE!!!!!

I had very similar problems last fall. Mechanics took off carbs, cleaned them, that was it.

Bad gas yes.

He said that the injector/jet/gas sprayer thingy gets clogged with crud over time.

Runs great now. When mine went bad I had about 2o miles to go and top speed was 1300rpms...trolling motor speed! LONG DAY