Fuel pump, solenoid, and stalling,... Need some help

[Drifter85258]

Need some help with where I should look.,.. Have an odd stalling problem with both engines. When in neutral and at idle, both (not necessarily at the same time and usually one or the other) engines stall from time to time. They simply just stop running with no reason. They will start back up. The boat runs fine otherwise. No codes being sent to smartcraft. Obviously this usually happens at the worst time (docking) as I put the boat in and out of gear.

here is an interesting piece of information, if I bypass the solenoid [completely unplug at the solenoid ("parkers" that shut off the fuel from the tank prior to the pump) and the fuel pump and also put into "bypass" position] the boat never stalls. This means the throttle is plugged into the fuel pump and not through the solenoid(s) then to the fuel pump (I think).

i just replaced both solenoids thinking maybe that was the problem but no luck. Any ideas? Could this be the cables maybe? Seems odd it would be both engines?

 

[Drifter85258]

Worth adding, it has new fuel filter / seperator also (cool fuel gen 3).

Read a ton and will probably replace iac next but any idea is welcome!

 

[perryk123]

Sounds like key on power might be intermittent. Those solenoids open and close with key on power. Wonder if your contacts might be corroded or possibly the wire itself or bad ground.

Are they getting hot?

 

[h_gerry]

I am wondering if it is the neutral safety switches in the shifters malfunctioning. I know for I/Os, the switches actually stall the engines momentarily as they shift.

 

[rondds]

Doubt it's the IAC b/c that would throw you into GUARDIAN mode, which means you can't exceed 1400 (?) RPM until the code is cleared. How old are your plugs? I had a problem with very hard cold-starting this spring until I replace the plugs. Smartcraft may not pull up ALL codes. I wonder if plugging into the ECM would get you a quick diagnosis.

 

[Drifter85258]

Thanks guys! I worried I was on my own. Appreciate the thoughts. I am really thinking this might be some type of connection thing that is shared between both engines and is only related to the wiring chain that the solenoids are connected to. My problem is I can't seem to find a wiring diagram for the solenoids. You guys know where I might be able to find one? Is it in the books I have with the boat? I have looked through the manual and the engine manual and they seem to both leave out how the solenoids are wired and connected to the fuel system. What I am looking for is where all the potential connectors are?

 

[Drifter85258]

Sounds like key on power might be intermittent. Those solenoids open and close with key on power. Wonder if your contacts might be corroded or possibly the wire itself or bad ground.

Are they getting hot?

even if I put them in bypass, as long as they are in the connection chain, I stall at idle (never when in gear or at least not yet). Will check if they get hot but don't think so

 

[Drifter85258]

Doubt it's the IAC b/c that would throw you into GUARDIAN mode, which means you can't exceed 1400 (?) RPM until the code is cleared. How old are your plugs? I had a problem with very hard cold-starting this spring until I replace the plugs. Smartcraft may not pull up ALL codes. I wonder if plugging into the ECM would get you a quick diagnosis.

plugs new this year. If I haven't got it figured out soon, will get someone out with the ability to check. I find it odd it runs fine as long as the cool fuel is connected direct and not in the solenoid "loop".

 

[Drifter85258]

I am wondering if it is the neutral safety switches in the shifters malfunctioning. I know for I/Os, the switches actually stall the engines momentarily as they shift.

Hmm, would that be post the fuel pump in the solendoid loop?

I think I should clarify what I do to make the problem go away. At the cool fuel there are 3 plugs. I understand the one goes to the solenoid then back to the cool fuel and plugs into the cool fuel. If you unplug the wire going to the solenoid at the cool fuel, unplug the cool fuel from the solenoid return line, and plug the cool fuel directly to the plug that was plugged into the wiring going to solenoid, the boat runs fine (solenoids in bypass).

If I plug it all back together correctly and put the solenoids back to "norm" it runs fine but has the random stall in idle problem mentioned below. If I let it sit at the dock running for long enough, eventually it just stalls also. Like you just turned it off (ground?)

so I am deducing that it is something in that wire that goes from the cool fuel to the solenoid but before I just start pulling wires, wondering if there is a "obvious" spot I should try first. Given it is both engines, a common ground for those two wires maybe?

 

[sdleo26]

Could be IAC, mine was no good, did not go into guardian mode, just annoying beep every minute and would not idle.... interesting it's on both motors though ....

 

[Drifter85258]

So went through every connection on the chain, used pb to clean each connection (and wire brush) and then some dielectric grease. So far, neither engine has stalled,.... Fingers crossed, I didn't just jinx myself,...