Port Engine stalling

Davpet60

Member
Joined
Aug 17, 2015
Messages
17
Reaction score
0
Points
1
This is the second year I'm fighting this issue, and techs can't seem to find anything.

Twin 2005 F225TXR OBs on a Grady White 282. Both engines start right up, pull out of the slip, about half way down the lane at 4-5 mph, port stalls. Try to restart, no luck, but after a while heavy gas smell. Continue on the way out, 15 - 20 mins later try restart, fires right up, quickly increase power to that engine..no problems.

Starting to wonder if this is an injector issue? Cant be gas, starboard runs no issues. Changed out all filters. Changed plugs, techs say the pumps are fine.... anyone have similar issue??
 

Sharkbait282

Well-Known Member
Joined
Mar 29, 2015
Messages
115
Reaction score
8
Points
18
Age
43
Location
Newport, RI
Couple of ideas for you, we've also battled intermittent low throttle stall on one of a pair of F225.

On our 282 sailfish (2002 vintage), the anti-siphon valves were shot, so we replaced those (under the deck plate, there are 4 total, 2 on each tank). I thought potentially they could have been pulling the balls closed in the wrong direction . . . maybe not all of the issue.

Clean VST filters, F-filters, on-motor filters, and 10-micron canisters is necessary . . . BUT, they MUST be sealed correctly. The on-motor filter especially with ethanol fuel can fail to correctly seat and seal, causing a potential fuel leak/smell, or loss of prime.

I recently identified that the mating surfaces under the 10-micron canister mounts are heavily corroded. Any set of seals throughout this system that causes an air-leak can cause an intermittent down-speed/low throttle stall.

Does the heavy fuel smell follow repeatedly pumping the fuel primer bulbs?
Are there any cases where you find the fuel bulb is collapsed flat?

The good news? You can take pretty much everything on the motors apart with a 10 and 12mm socket and one extension. The bad news is there's so much to take apart to get to things like the VST screen, that it's easy for something to not quite seal correctly and cause a tricky problem.
 

seasick

Well-Known Member
Joined
Aug 19, 2008
Messages
9,073
Reaction score
1,293
Points
113
Location
NYC
You can try swapping the fuel feeds between the motors. Swap as close to the motor as possible, after the primer bulb is good. If the problem switched to the other motor than you have a fuel delivery issue. If not, most likely you have a motor issue.
Although I also thought of an injector issue, it would have to affect most if not all injectors and that less likely. The smell of gas tells me that the motor is getting gas, perhaps too much. That could be related to a bad sensor ( engine temp) that is causing the motor to think it is colder than it really is and then runs way too rich causing flooding and fouling of the plugs. A clogged O2 sensor can cause a rich mixture but that wouldn't explain why the motor starts after sitting. That need to wait is common for flooded motors. So is it too much fuel or not enough? Swap lines and see.
One option is to have a mechanic download the diagnostic info for the motors
 

Davpet60

Member
Joined
Aug 17, 2015
Messages
17
Reaction score
0
Points
1
Thanks guys... I'm going to copy this and sent it to the yamaha tech.... great ideas.
 

seafarer94

Member
Joined
Jul 23, 2016
Messages
16
Reaction score
0
Points
1
I know you said its not pumps, but I just had the same problem with the electric fuel pump not working all the time. Mine ran fine at higher rpms and died at low rpms. Good luck finding your issue.
 

Ky Grady

GreatGrady Captain
Staff member
Joined
Mar 1, 2006
Messages
2,914
Reaction score
1,271
Points
113
Location
Berea, KY/Cross, SC
Model
Seafarer
Just took mine out today after the overhaul/cleanup. Motor ran fine when I started this back in April when I bought it.

2004 F225 with 1190 hrs. Have to keep primer bulb full and pressure against the bulb or motor will die. New Yamaha fuel/water separator kit, new fuel filter on motor, no leaks or fuel smell. Pumped out both tanks and started with all fresh fuel. Did not look at anti siphon valve yet. Going to go through the trouble shooting of the fuel system tomorrow. Leaning towards the LP pump, LP fuse or relay, VST pump/filter or combination of all of them.
 

seasick

Well-Known Member
Joined
Aug 19, 2008
Messages
9,073
Reaction score
1,293
Points
113
Location
NYC
Ky Grady said:
Just took mine out today after the overhaul/cleanup. Motor ran fine when I started this back in April when I bought it.

2004 F225 with 1190 hrs. Have to keep primer bulb full and pressure against the bulb or motor will die. New Yamaha fuel/water separator kit, new fuel filter on motor, no leaks or fuel smell. Pumped out both tanks and started with all fresh fuel. Did not look at anti siphon valve yet. Going to go through the trouble shooting of the fuel system tomorrow. Leaning towards the LP pump, LP fuse or relay, VST pump/filter or combination of all of them.
A fuel rail pressure test will help determine if the problem is in VST or before it. Sounds to me like a problem with the fuel pump ( I call that the lift pump as opposed to the low pressure pump but I guess it is the low pressure pump). You can check that it is getting power but remember that most Yami electric devices get constant +12 volts and switch the ground to activate/deactivate. I doubt that anti-siphon is an issue because if it were, you probably couldn't get gas to flow just by squeezing the bulb.

Check the onboard fuel filter if it is the bowl type for air leaks especially if you recently changed the cartridge.
 

Ky Grady

GreatGrady Captain
Staff member
Joined
Mar 1, 2006
Messages
2,914
Reaction score
1,271
Points
113
Location
Berea, KY/Cross, SC
Model
Seafarer
seasick said:
A fuel rail pressure test will help determine if the problem is in VST or before it. Sounds to me like a problem with the fuel pump ( I call that the lift pump as opposed to the low pressure pump but I guess it is the low pressure pump). You can check that it is getting power but remember that most Yami electric devices get constant +12 volts and switch the ground to activate/deactivate. I doubt that anti-siphon is an issue because if it were, you probably couldn't get gas to flow just by squeezing the bulb.

Check the onboard fuel filter if it is the bowl type for air leaks especially if you recently changed the cartridge.

Thank you sir. I'm leaning toward lift pump also. Either a fuse, relay or pump itself. After a Google search last night, a thread on THT came up and a guy had same issues. Getting ready to get into it this morning and I'll post my findings. When I pumped my tanks out, clearly had phase separation of gas and ethanol, that's what had me thinking of the VST tank, but as long as you keep the primer bulb full, motor runs smooth. It goes to sputtering, almost backfire sound when it starts running out of fuel, pump bulb back up, runs fine till it starts running out again.

I did just change onboard filter also and will recheck that as well
 

Ky Grady

GreatGrady Captain
Staff member
Joined
Mar 1, 2006
Messages
2,914
Reaction score
1,271
Points
113
Location
Berea, KY/Cross, SC
Model
Seafarer
Ok,

5 amp fuse blown, replaced, blown again. Put 7.5 amp in and it's holding. Pump cycles like it's supposed to. Ran it up to 2K on the hose and fuse still good. I think the pump cycles until you're over 1200 rpm, then it goes steady pump to keep VST full. Correct me if I'm wrong.

Even though it's holding, I'll always wonder when it'll go out and ruin a trip. So I guess I'll suck it up and order a new pump.
 

seasick

Well-Known Member
Joined
Aug 19, 2008
Messages
9,073
Reaction score
1,293
Points
113
Location
NYC
I found a lot of posts on other boards about the fuse popping.
Here is an excerpt from a post on the yamaha outboard forum about how the system works and what could be the issue

a short between the pump and the fuse.

a short in the pump brush/commutator.
a locked up pump.
an overheated pump(lack of fuel).
and back to that relief valve, if that valve sticks shut the pump will run in a stalled condition when the VST needle is closed.
this can also cause heat and blown fuses.

see how stupidly simple this is?

at key on the lift pump is supplied with 12v via a 5 amp fuse.
once running the ECU supplies the ground path to run the pump.
below 1200 RPM this path is applied for 10 seconds and taken away for 20 seconds.
above 1200 RPM this path is continuous.

the reason?????
below 1200 RPM the pump can supply way more fuel than the VST can handle.
to prevent the pump from running in a stalled condition at low speeds they cycle it on and off.


Replacing the fuse with a higher capacity fuse is not wise.
I would look for a fuel constriction or a blocked relief valve as noted. Logic leads me to suspect that a stuck relief valve would make the fuse popping problem occur more at lower speeds and loads while the fuel restriction cause would make the fuse more likely to pop at higher speeds and loads. Of course, the pump could be bad but before shelling out $500 for a new one, you might want to look at the other possibilities.

Let us know how it goes.
 

Ky Grady

GreatGrady Captain
Staff member
Joined
Mar 1, 2006
Messages
2,914
Reaction score
1,271
Points
113
Location
Berea, KY/Cross, SC
Model
Seafarer
seasick said:
I found a lot of posts on other boards about the fuse popping.
Here is an excerpt from a post on the yamaha outboard forum about how the system works and what could be the issue

a short between the pump and the fuse.

a short in the pump brush/commutator.
a locked up pump.
an overheated pump(lack of fuel).
and back to that relief valve, if that valve sticks shut the pump will run in a stalled condition when the VST needle is closed.
this can also cause heat and blown fuses.

see how stupidly simple this is?

at key on the lift pump is supplied with 12v via a 5 amp fuse.
once running the ECU supplies the ground path to run the pump.
below 1200 RPM this path is applied for 10 seconds and taken away for 20 seconds.
above 1200 RPM this path is continuous.

the reason?????
below 1200 RPM the pump can supply way more fuel than the VST can handle.
to prevent the pump from running in a stalled condition at low speeds they cycle it on and off.


Replacing the fuse with a higher capacity fuse is not wise.
I would look for a fuel constriction or a blocked relief valve as noted. Logic leads me to suspect that a stuck relief valve would make the fuse popping problem occur more at lower speeds and loads while the fuel restriction cause would make the fuse more likely to pop at higher speeds and loads. Of course, the pump could be bad but before shelling out $500 for a new one, you might want to look at the other possibilities.

Let us know how it goes.


Thanks

I did pull the relief valve and made sure it was clean, functioning and not stuck either open or closed. It was ok. The new lift pump arrived today but didn't get it put on. Should be able to tomorrow