1999 Evinrude (90 hp) E90FPLEEC - Runs fine at idle speed. But stalls when running about 3000 rpm

[sfree1965]

(90 hp) E90FPLEEC - Runs fine at idle speeds. But when trying to run above 3000 rpm, motor stalls after about 5 minutes. Like it's not getting gas. When it stalls, only thing I do is pump the primer bulb a couple of times, wait about 3-4 minutes and it starts back up. Now the other side of the this problem, doesn't do it all the time!

All suggestions? Everyone around me thinks fuel pump needs rebuilt. Unable to find rebuild kit or fuel pump. ( 5004454 Fuel Pump Kit)

 

[Crosbyman]

don't assume the small lift pump is bad you also have the fuel filter asa possible source of restriction....then the VST needs to vent properly otherwise entry into the VST of new fuel will be compromised . Check vst top cover for a small float valve/needle which closes when the VST is full of fuel. A stuck needle will prevent vapors from exiting the VST causing a pressure build up.. in theory anyway


BTW similar looking VST,s on the more modern ETECs have a small conical filter ...not certain if yours has one but be very careful not to break VST fuel nipples if you do check .


if it is that small lift pump and truly NLA and you are up the creek you may be able to adapt something up with a common pulse pump of similar size. Or... if need be you could try to cut yourself a diaphragm if that is the issue ..check valves being OK of course .

I realize the oiling system - vro is complex but if all else fails some folks run premix and you can always mount an external 10 micron filter.


more from the experts....

 

[sfree1965]

don't assume the small lift pump is bad you also have the fuel filter asa possible source of restriction....then the VST needs to vent properly otherwise entry into the VST of new fuel will be compromised . Check vst top cover for a small float valve/needle which closes when the VST is full of fuel. A stuck needle will prevent vapors from exiting the VST causing a pressure build up.. in theory anyway


BTW similar looking VST,s on the more modern ETECs have a small conical filter ...not certain if yours has one but be very careful not to break VST fuel nipples if you do check .


if it is that small lift pump and truly NLA and you are up the creek you may be able to adapt something up with a common pulse pump of similar size. Or... if need be you could try to cut yourself a diaphragm if that is the issue ..check valves being OK of course .

I realize the oiling system - vro is complex but if all else fails some folks run premix and you can always mount an external 10 micron filter.


more from the experts....

don't assume the small lift pump is bad you also have the fuel filter asa possible source of restriction....then the VST needs to vent properly otherwise entry into the VST of new fuel will be compromised . Check vst top cover for a small float valve/needle which closes when the VST is full of fuel. A stuck needle will prevent vapors from exiting the VST causing a pressure build up.. in theory anyway


BTW similar looking VST,s on the more modern ETECs have a small conical filter ...not certain if yours has one but be very careful not to break VST fuel nipples if you do check .


if it is that small lift pump and truly NLA and you are up the creek you may be able to adapt something up with a common pulse pump of similar size. Or... if need be you could try to cut yourself a diaphragm if that is the issue ..check valves being OK of course .

I realize the oiling system - vro is complex but if all else fails some folks run premix and you can always mount an external 10 micron filter.


more from the experts....

Thank you for the reply..
I've replaced the fuel filter twice this summer. It appeared to be very clean. Little to no residue / sediment.

I've never messed with the VTS. I'm assuming you are referring to this



I don't know if it would fix my problem, but I'm assuming less parts involved. If I wanted to do away with the oil system and goto premix. What parts and adjustments are needed...

Thank you,

Scott

 

[Crosbyman]

first things first... up to you...

.me I would just open the VST to check the vent float and needle. VST is just a can with a water coil to cool the fuel and let vapors escape via the top needle valve. they have been know to become stuck/rusty if the incoming fuel is contaminated with water.

On modern ETECs fuel is then passed on to a high pressure pump to feed injectors

I can't specify needed parts for pre-mix but you do need a pulse pump, a filter and distribution of fuel to carbs.

try the easy stuff first

 

[racerone]

The motor can not be made to run on 50:1 mix !!!----Need to accept that fact.

 

[Crosbyman]

well there you go... better fix what ails it then ...

Racerone.... any technical reason why premixing would not work .. be it 50/1 or 40/1
if the needed parts are truly NLA anywhere ? Is it the end fatality of the engine ?

 

[racerone]

The----f----makes it a fuel injected motor.-------Fuel goes into the combustion chamber ( like a 4 stroke ) and the crank and bearings would not get oil !!!!

 

[Crosbyman]

good point .... had not noticed the injector in the parts diagram

your the man...as always

 

[CaptnKingfisher]

Ran into this issue on a friend's boat, took a sample from the gas tank and it was loaded with crap and water. When the rpms were increased the fuel demand was increased and the filter and water seperater weren't as effective, causing the boat to stall. Suggest ruling out bad fuel before moving on to more difficult possibilities. I like to keep a portable tank handy with fresh gas when I'm diagnosing fuel related issues