2006 F250 issue. Update

[SeanC]

Took the boat out for a run today. Get up cruising speed of about 30mph then the motor starts to lose rpm down to about 12-15mph. Put into neutral for about 30 seconds, get upto cruising speed and the same thing happens. If I give it more gas as the rpm drops the engine just dies but doesn’t stop. The priming bulb is still firm. Seems to be a fuel issue of some kind. Any thoughts?

 

[wrxhoon]

Did you check the fuel filter inside the cowling? Tank breather? I know to you it feels like fuel problem but don't discount spark plugs if you haven't changed them put a new set in , they are cheap and easy to do.

 

[Clark.N]

Had this problem several years ago. Found I had clogged fuel injectors. Dealership cleaned and problem resolved.

 

[seasick]

Symptoms are those of fuel starvation. Likely causes are clogged VST screen, clogged filter, clogged regulator screen or even an air leak in the plumbing such as a not seated correctly fuel filter bowl. It cold also be bad low pressure/lift pumps. Other than opening the VST to check the filter, one way to isolate is to use a fuel pressure gauge on the fuel rail fitting to see if the pressure drops as you speed up.
Here is a link to the VST work. It isn't for the total mechanical novice

Yamaha Service Information - F225 Service Information - VST Removal, Cleaning, Filter/Screen Replacement - SIM YAMAHA

www.simyamaha.com

 

[wspitler]

Agree with seasick. I had the exact same problem with my 2006 F250s and replaced the VST and LP filters. After replacing the filters the motors ran better than before, no problems, higher top end RPM. Suspect that will do it for you. VSTs looked bad, but still flowed but not enough for good performance.

 

[SeanC]

Thanks guys I'm going to blame dodgy Yankee fuel that came with the boat.

 

[Sparkdog118]

If you need injectors, I have had good luck with the aftermarket injectors from eBay.

I have them in mine and I know of 10 other motors that have them with no issues.

Purple Fuel Injector 6P2-13761-10-00 4 Holes For Yamaha Outboard | eBay

We will do everything we can to give you a satisfying solution.

www.ebay.com

 

[Sparkdog118]

Long video but Has a lot of useful info.

 

[seasick]

That was informative. Thanks

 

[Sparkdog118]

It is a pretty good video. Very welcome.

 

[JAdams1]

Just went through this with my 2006 F200, inlet filter on the fuel pump located in the VST tank was dirty, injectors were ultrasonically cleaned and the filters in the injectors were replaced. I was limited to 4,000 rpms before the work.

 

[Summertop511]

Vst tank

 

[seasick]

JAdams photo of the VST filter is a great example of a really clogged screen. Sometimes, the filter doesn't look so dirty. Th way to tell is to aim it towards light and look through that hole. Hold your spread fingers behind it and look for them through the hole. If you can't make out your fingers, the screen is dirty.

 

[seasick]

Just went through this with my 2006 F200, inlet filter on the fuel pump located in the VST tank was dirty, injectors were ultrasonically cleaned and the filters in the injectors were replaced. I was limited to 4,000 rpms before the work.

Did you have the white grit in the bottom or sides of the VST tank?

 

[Ky Grady]

This was my VST filter. Cleaned it, and had my injectors cleaned by Flagship Marine in Florida, runs like a champ.

 

[seasick]

Perfect shot! Thanks

 

[Ky Grady]

Bottom side.

 

[Sparkdog118]

This was my VST filter. Cleaned it, and had my injectors cleaned by Flagship Marine in Florida, runs like a champ.
View attachment 13793

Flagship does a great job cleaning injectors. I was just there Friday to pick up 12 Optimax injectors for a customer. I usually buy the new ones off the internet (eBay)for the Yamahas. They are cheaper than having the old ones cleaned and have the same numbers stamped on them. Actually some automotive injectors cross with Yamaha injectors. I know Mitsubishi gallant have the same injectors as the f115. I have found a set of 4 injectors for under 40 bucks.

Fuel Injector fit for Yamaha Mitsubishi Eclipse CDH210 / INP771 Flow Matched | eBay

Other Part Number: INP771. Manufacturer Part Number: CDH210, 842-12223. Fuel Injector x 1. For 1999-2003 Mitsubishi Galant 3.0L V6. For 1997-2001 Mitsubishi Mirage 1.8L. For 2000-2015 Yamaha Outboard 115HP.

www.ebay.com

 

[wspitler]

A partially clogged VST filter on an F250 looks like this. I had the same symptoms as SeanC.

 

[Sparkdog118]

On rare occasions, cleaning the vst filter did not work. I’ve had to replace the filter to get it to pass sufficient fuel through. I usually put new ones in the first round so I know it is going to be ok.