Yamaha F225 fuel starvation on re-start

[CaribSurf]

If anyone has experienced the following,I'd be interested in any advice
I have a pair of 2002 F225 TXRA Yamaha's. The port side ocassionally suffers fuel loss & inability to start, due to the VST evaporating all the fuel out ( empty) after a run of 25 minutes. When you have stopped for about 25 minutes & go to re-start, engine wont run.You have to prime the fuel primer bulb, then it fires right up. I've checked everything back to the tank.Vessel has a brand new fuel tank,(no anti-siphon check valves) all hoses,Racors & primer bulbs, during a fuel tank replacement this year. The symptom I'm seeing is the heat of the engine after a run, evaporates the gasoline when the engine is stopped, so the VST is empty when you re-start.Its also an intermittent fault,doesnt do it all the time( frustrating to find a cause).I'm thinking a ventilation fault with the VST or somewhere in the fuel system.I've noticed it become evident this past month, as our daytime tempertures are now 90 degrees on the water, summer has arrived.

[99yam40]

do not know if this will help you but Yamaha recomends running the motors for some(?)period of time at idle before sutting them off after a good run so they will cool off some

[boscoe99]

Have you actually verified that the VST is empty? That is, if the drain to the VST is removed and the VST is vented to allow air in, then no fuel comes out?

Yamaha has a bulletin out to address this or a similar issue but if the motor ran fine for all then years and is just now acting up, it may or may not be a related issue.

Questions for you. Where are you located? Is perhaps your fuel tank filled with winter blended fuel?

2002 ~ 2004 F225, LF225, F200, LF200
Engine Hesitation or Stalling after Prolonged Idle
PAGE 1 of 5

Symptom: Some units, in the affected range, may experience a hesitation after a hot restart or may stall after a prolonged period of idling or *****ing.
Cause: The combination of regional winter fuel blends and high ambient temperatures can lead to an accumulation of vapor in the fuel lines. Eventually, this can lead to low fuel levels in the Vapor Separator Tank (VST) resulting in the hesitation or stalling.
Remedy: Install the Vapor Recovery Kit (see the Service Procedure section, page 2).

[rodbolt17]

if all it takes is a simple reprime with the primer bulb then one of the 2 oneway relief/check valves have failed.
one is for VST pressure and is located between the lift pump inlet and VST inlet the other is the VST vent and is located in the airbox.

its a dirt simple system.

kick a lot of tech butt.

until that VST hits about 10 PSI with vapor ,fuel cant escape unless the VST vent is bad.

its not evaporating.

[CaribSurf]

Thanks to everyone for the advice.Just to follow up, the boat & engines I have only owned since January '14, so still getting some new ownership bugs out.
The vessel ( formerly a FL boat) now lives in the Caribbean. Our fuel here is decent quality non-E10 fuel. I had a feeling the engine was running warmer than its STB-side companion, so replaced both thermostats this weekend. Found one not opening fully,when I tested it (on the left-bank). Also found the vent-orifice check valve that vents the VST to the inlet air-box stuck open ( replaced that with a known functioning one) .The engine also has the VST recovery & vent system fitted, so removed & cleaned its parts & check valve. I tested the fuel inlet supply check valve you mentioned, found it good. After a repeat test run yesterday, did not see the fuel starvation problem again. I did give the engines a 5 minute cool-down at idle after a run also. Hope the above & your comments help anyone else with a similar fault.

[gazman51]

'03 F200 Engines - Stalling Near Idle Speeds

I'm new to this forum and was reading the thread pertaining to your engine stalling problems. Do your engines have the VST "Canister Modification"? It was recommended by Yamaha as a retrofit kit for warm weather customers who experienced stalling problems after running. The dealer and Yamaha mechanic in my area do not recommend the retrofit kit and Yamaha charges a bundle for the separate parts to modify the VST canister. BOth sources recommended that I pump the fuel bulbs up before starting the engines and let the engines idel for a while before shutting down. I may have received at least 1/2 tank of E10 fuel and several other boaters mentioned that the E10 fuel will vaporize quicker than the zero ethanol fuel. Can you confirm this? I'm getting very tired of coasting into docks without any power.

[rodbolt17]

what part of the canister modification aint gonna help your issue are you having problems with ????????
ALL that canister mod did was reroute vapors at engine SHUT DOWN to a charcoal canister INSTEAD of the air box.
other than that it does NOTHING when running.
later engines actually used a VAPOR SHUT OFF valve.
however its your money,spend it as you wish.