Yamaha 150 4-stroke injector issues

[walleyehunter9]

I have a Yamaha 150 and I am having some issues. RPM's are only getting up to 4800 or so and will let back 400-600 RPM at that speed. Dealer says it was a bad injector so they changed only one and the problem has not changed much. Any help? :banghead:

Previous owner never ran stabalizer which hurts I'm sure. I am thinking of running ring free or stabil???

Also I am going to install a fuel/water seperator. Motor is an 04 and warranty is almost up...

Wouldn't a warranty issue replace all four injectors at once instead of one?

Any help would be greatly appreciated.

[PJM]

Walleyehunter

I would like a little more information on your set-up. What boat are you running and what prop. What is the best rpm you have ran ?

[walleyehunter9]

Boat is an Lund 1800 Fisherman and under normal conditions was getting 5900RPM. Prop is a 3 blade stainless steel raptor.

hope this helps....

Thanks again

[srj]

You may have a load of gas with crapola in it. It's possible a bad/plugged injector was replaced then another injector plugged when you ran the boat again. A canister fuel filter/seperator is a must have item with efi motors and a good idea for all boats.

I had an injector issue with my F115 shortly after buying my Yarcraft. I also had a tank of gas with serious particulates floating around (unknown at the time). I had delayed installing my canister filter and sure wished I hadn't, as a second injector plugged shortly after the first one was replaced. You might want to examine the gas currently in your tank--a few ounces in a white cup might show any particulates. After sitting a bit, they would settle to the bottom. I had to siphon my tank.

It sounds like another trip to the dealer is in order. And no, they would not replace all the injectors.

Good luck.

[PJM]

walleyehunter

What pitch prop and when did the problem start?

[walleyehunter9]

I believe it is a 21 pitch raptor prop. The issue started at the beginning of last year. This motor should get 6000 RPM and right now is getting 4600RPM at full throttle and will back off on its own by 200-400 RPM

Three things I am going to do after the dealer finds out what the issue is ( I think the other injectors are bad)
1. fuel-water seperator
2. Stabil every fill up
3. Ring free every fill up

[PJM]

Walleyehunter

The people that I know that have that boat run a 17 to a 19P depending on the load and I'm wondering if you have a prop issue if you are running a 21P

[Lundexp]

What rpms were you getting before the problem started?

[went522]

What rpms were you getting before the problem started?

"--------------------------------------------------------------------------------

"Boat is an Lund 1800 Fisherman and under normal conditions was getting 5900RPM."

Walleyehunter9...your issue is most likely stemming from the lack of a seperator, for sure get that installed. No need for stabil every fill up unless your letting it sit for extended periods of time. Either ring free or seafoam with every tank will sufice. I personally add seafoam every 2-3 tanks and save the stabil for the last tank before putting it away for the season.

Seperators are now recommended equiment on boats rigged with 4 stroke yamahas. What your dealing with now is the reason they made them "standard".

BIRDDOG

[Hawgeye]

I run a 21P prop on my F150 on an 1800 ProV and get 5900 RPM's as well. That is the right size prop for your boat. Can't help you with the RPM problem though..good luck.

[walleyehunter9]

I apologize, the stainless prop on my motor is a 19 pitch. The boat ran great for 3 years and the problem started last year which kind of tells me the prop is not the issue. I still believe the problem is the injectors. I think all four of them need to be replaced and so far the dealer has only replaced one.

[REW]

Walleyehunter.
1. Drain all of the gas from your boat
2. Install a 10 micron water fuel separator on your rig, if you don't have one installed.
3. Flush all of the fuel lines.
4. Install 4 new injectors.
5. Refill the gas tank with fresh gas.
6. Go out and enjoy your rig running correctly.

REW
p.s.
Continue to add fuel stabil or the equivalent every other tank of gas.
Be sure to add gas from a good source.

[bigstick]

I have a F150 and ran into the plugged injector issues .... I did as REW suggested , It fixed the problem of low rpm's & no power, and have had no repeat of the problem in 3 years ..GOOD LUCK!

[walleyehunter9]

Thank you for all the help with this issue. Iam glad to say that after having all the injectors replaced and installing a new fuel-water seperator, the boat is running like new and allowing me back out on the detroit river to jig up all these walleye...:rock-on:

Thanks again for your time.