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Major engine problem

Beachbummer

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When you recovered the oil.. How much were you able to extract?
 

tahmad575

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@bronze_10 how come your ecu's kept going bad? Was it that they were getting wet?
@Beachbummer from the starboard engine I have been able to get out 3 quarts with the suction method, I'm going to do a complete drain by taking out the drain plug to gauge exactly how much was in there. I have not yet done the port but I will get back to you on that one as well
 

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Ok, Unless it was overfilled before that is indicative of an open injector. Yds has an injector test where the injector is forced to click rapidly, and it can be heard. If you run the test and the injector does not click, it could be s faulty injector but so far everyone that had it happens... It has been the ECU.
 

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Update: there's a small amount of water? At the bottom of fuel starboard engine fuel sample. Not too sure if it's water but it looks clear and moves almost like hand sanitizer at the bottom of the bottle.
Port engine fuel sample is showing no signs of seperation and is clear

Pulled the fuel samples out 15 hours ago.

I have attached pics of the starboard engine fuel sample only, with and without flash
*16oz sample, 50 gallons tank so multiply the amount of water in the sample by 400x's to get an idea of how much contaminant is in the tank*
 

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tahmad575

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@Beachbummer is there a way I can check without the yds since I don't have a pc laptop I can't run that test yet.

Wondering if I can use my multimeter and get a friend to crank the engine and if a fuel injector wire has a constant voltage I will know for certain it's being told to stay open correct?
 

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A digital voltmeter would not update fast enough to keep up with an engine, even at idle. An analog meter might work but not ideal. The injector should fire 4.1 times per second at only 1000RPM.
 

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@Gym that's what I was hoping wouldn't be the problem but you're right. So what are the next steps I need to take? After checking the ECU for water
 

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You could search the board for any YDS owning member nearby willing to lend you the tool.

It does appear you have a lot of water in the tank... But water will go to the bottom, no no guarantee that the rest of the tank has as much water as your sample (since the fuel pump draws from the bottom)


You could try finding someone willing to clean the tank... Or you could purchase a water separator and some hoses to run the fuel through the filter a few times. Disconnect fuel hose from engine, hook up to fuel/water separator, and feed back to tank via gas refill hole. I have done this before on another boat successfully.

Something like



I'm not yet sure if you ecu has a problem or not, but that's a lot of weird stuff on the fuel.
 

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I have done this to troubleshoot a coil... You could place a low draw light, like a 12v LED in place of each injector and crank. (No idea how to turn off fuel pump during) leds should flash on each pulse, I would think.

If someone thinks this is a bad idea please say so. I'd try it if YDS was not available.
 

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I have done this to troubleshoot a coil... You could place a low draw light, like a 12v LED in place of each injector and crank. (No idea how to turn off fuel pump during) leds should flash on each pulse, I would think.

If someone thinks this is a bad idea please say so. I'd try it if YDS was not available.
Perfectly fine test. You could do this with a normal 12v test light. They also make a device called a "noid light" for doing this test as well. The only problem with this test is knowing whether your 12v pos injector feed is the problem or the ecm controlled switched ground is the issue. So pull an injector connector and with the key on, one of the two terminals should have power. The other terminal is switched ground. Then assuming that test passes, connect your light in place of the injector and see if it blinks when the engine is being cranked. To prevent the engine from firing or flooding, unplug all the coils and all the injectors.
 

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@Beachbummer thanks for the tips and I'm going to order 2 water/fuel seperators tonight, going to install them on both engines after getting rid of all the water in the tank.
That's a great tip for checking the pulse on the injectors thanks 👍 I'll try that tonight after work.
@Sbrown I'll disconnect all the spark plugs and I will disconnect the fuel pump wire over the gas tank for each engine. This should prevent fuel from getting out of the tank

Thanks for the advice everyone I will keep you posted on my findings tonight
 

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@Beachbummer thanks for the tips and I'm going to order 2 water/fuel seperators tonight, going to install them on both engines after getting rid of all the water in the tank.
That's a great tip for checking the pulse on the injectors thanks 👍 I'll try that tonight after work.
@Sbrown I'll disconnect all the spark plugs and I will disconnect the fuel pump wire over the gas tank for each engine. This should prevent fuel from getting out of the tank

Thanks for the advice everyone I will keep you posted on my findings tonight
Sounds good, but dont just pull the coils off the spark plugs, make sure you actually unplug the harness from the coils. Disconnecting the fuel pump wires is great, but also make sure to unplug all the injectors to prevent flooding the engine with fuel.
 

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Just a hunch here @tahmad575. Whereas you mentioned a colorless, odorless slime on top of your fuel tank and then mentioned a clear solution that separated out of your fuel that you said moved like hand sanitizer rather than water. Is it possible they are the same material? If so this could have partially clogged your injectors on both engines. Is it possible to take a sample that dropped out of solution in your fuel sample bottle? If it has any viscosity at all it may be the culprit. Assuming your fuel samples are in plastic bottles all you would need to do is poke a small hole in the bottom where the water has collected and drain a small sample in another clean container.
 

tahmad575

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@Sbrown yeah I've taken out all 8 fuel injectors and am going to create some contraption to clean them with carb/air intake cleaner. I'll make sure to disconnect the spark plug wires as well, thanks

@buckbuck hell yeah when I first bought the boat I cleaned the engines real well, changed the spark plugs, fresh oil and filter and it ran like a champ the 24 times I took it out. I'll be honest..a half hour before sunset when the lake is empty of boaters and the water is glass I drop off my passengers and go on full speed runs at wide open throttle. I'll probably stop doing that now lol.

@Gym I used glass bottles but now that I've found something in the fuel I'm going to grab clear 1 litre soda bottles, dump the soda and collect a bigger sample from both fuel lines.
It honestly looks and behaves the same way as the clear slime that was on top of the fuel tank hatch, I'll try to extract it what I have right now with a syringe or like a turkey baster. I'll attach pictures later on tonight once I'm out of work
 

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@Sbrown yeah I've taken out all 8 fuel injectors and am going to create some contraption to clean them with carb/air intake cleaner. I'll make sure to disconnect the spark plug wires as well, thanks

@buckbuck hell yeah when I first bought the boat I cleaned the engines real well, changed the spark plugs, fresh oil and filter and it ran like a champ the 24 times I took it out. I'll be honest..a half hour before sunset when the lake is empty of boaters and the water is glass I drop off my passengers and go on full speed runs at wide open throttle. I'll probably stop doing that now lol.

@Gym I used glass bottles but now that I've found something in the fuel I'm going to grab clear 1 litre soda bottles, dump the soda and collect a bigger sample from both fuel lines.
It honestly looks and behaves the same way as the clear slime that was on top of the fuel tank hatch, I'll try to extract it what I have right now with a syringe or like a turkey baster. I'll attach pictures later on tonight once I'm out of work
Ok. Hope there's no more in the tank or it could mess up the injectors you're about to clean.
 

Gym

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By the way...It's not the full speed runs that have as many consequences as the quick stops. I've become very conscious of stepping the speed down in increments to avoid swim platform washout.
 

tahmad575

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@Gym yeah so do you suggest just draining the entire fuel tank then cleaning it somehow or running it through a water fuel seperator and cycling it back into the tank?
Also great tip I'll try to practice that to minimize wash over my rear swim platform.

Here's a video of me cleaning the injectors
They are really clogged but you can see the spray start to atomize towards the end
 
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