[mayday 57]

I can run at 1800 rpm and less and it will not die but when i run for a 1/4 mile sometimes less it dies like the fuel was shut of . let it sit 30 sec it fires up and runs. but when i was in calm water i ran at 4500 4 or 5 miles with no issue. any sugestions on where to start?

 

[oceansbreeze]

I would change the in lineand enginefuel filter and check the old ones for water and see if there is any kind of very smallrubber particlesin either one.

Have you try pump the primer bulb after it stop? Was it soft?

How old the boat?

How old the gas?

When was the last time it ran okay?

It sound like it may be a fuel problem.

 

[mayday 57]

the bulb was a little soft .

2001 boat.

pretty fresh gas w/stabil.

first time i have ran the boat since the sea trial but it did run perfect for 4 or 5 hours that morning.

 

[DOUBLE "D" & LV]

what 225 yamaha do you have? (carb, fuel injected, 4 stroke)

 

[mayday 57]

efi 2 stroke

 

[DreamWeaver21]

Change the fuel water seperator and the onboard filter element. See if that fixes it.

Next guess would be either low preasure fuel pumps or VST tank /filter cleaning.If it is not the filters then it sounds more like low preasure fuel pumps need replacedthana VST issue.

Do post what 225 it is.If it is an OX66 it is almost surely one or some combination of these three things.

edit* We posted at the same time. I have the same motor and have had the exact same issue a couple of times. Once the issue was a clogged filter element in the little onboard filter with the red ring in it. I took the element out for testing purposes and the boat ran fine. I bought a new filter element and was back in business. This was after I had it in the shop twice and spent $700 for nothing. Another time it was the low preasure fuel pumps getting old. They wear out but are pretty cheap at like $35 a piece (there are 3) and are easy to change.

Usually the VST issue presents at a brief cut out at speed when hitting a wave so it would be my third try. Is this on a 23 cobia?

 

[mayday 57]

ox66 yes 234 cobia

 

[DreamWeaver21]

PM sent. I'll be AFK for an hour or so though.

 

[JollyGreen]

PM sent

 

[mayday 57]

AFK ?

 

[DreamWeaver21]

Away From Keyboard.

 

[DOUBLE "D" & LV]

As Dreamweaver stated. Fuel filters etc. I have found low pressure fuel pump diaphrams bad, fuel lines kinked or deteriorated from alcohol, debris at the vapor seperator tank (VST) needle valve clogging the inlet, fuel filters clogged, air leaks from loose hose connections and filters not tight, anti syphon fittings sticking or clogged, fuel tank pickups clogged, and several other items. So, there is a list of items to check. Start with the fuel filters. Check the low pressure pumps for leaking diaphrams. (loosen them and squeeze the primer to see if they leak out the back). Check the fuel lines and tank fitting. Then it's to the more involved stuff. Hope this helps.

 

[mayday 57]

thanks to everyone for your sugestions .

so far i have checked the fuel water seperator didnot see any evidince of water.

checked the filter with the red ring no real debris to speak of and was able to blow through the filter as it is completly free flowing.

pulled the brass screw on the side of the vst and drained what looked like a good clean mix of gas and oil as it was colered slight green or blueish but clean none the less.

 

[JUST-IN-TIME]

mayday 57 (1/23/2010)thanks to everyone for your sugestions .



so far i have checked the fuel water seperator didnot see any evidince of water.



checked the filter with the red ring no real debris to speak of and was able to blow through the filter as it is completly free flowing.



pulled the brass screw on the side of the vst and drained what looked like a good clean mix of gas and oil as it was colered slight green or blueish but clean none the less.

These motors have an 02 sensor and a TPS, that controls fuel flow



If it was in my hands i would do this



- Fresh fuel supply

- Vacuum gauge after fuel filter

- replace the VST screen

- change spark plugs, compression check same time, E-Z

- get TPS readings



after i ran it, i would pull plugs and read them



these motors had bad fuel pump diaphragms, you can tell by the white plastic on fuel pumps

also your bottom plugs would be soaking wet from raw fuel



it sounds to be o2 sensor or TPS, but i could be wrong

 

[Sequoiha]

it almost sounds like a good old fashioned link and sync,, and service the o2 sensor would take care of it,

the sensor needs to be taken out and the heater circuit needs to be checked and it needs to be cleaned,, ill bet the transfer tube is completley stopped up,,,,