Plugs keep fouling - any thoughts??

[chrislandy]

Yes but those pictures look much worse than the ones you posted up last week. You keep saying "it runs fine", which is what keeps me heading towards the sensor readings. It might be worth buying the MEFIBurn software so you can see what the ECU is seeing and doing, it's great for diagnosing issues (logging, live readouts etc)

I can't remember seeing what sort of use you putting the boat though and whether you've given it a good blat, then turned off and checked the plugs etc, whether you have 20min idle to and from the ski zone or whether you can ski off the dock, all these things need to be considered when inspecting plugs. Are you chugging along fully laden surfing, no/full ballast and boarding or running 26/28/30/32/34/36 mph and course/free skiing - and at which point are you checking the plugs? - everything may be fine but you're just hitting a rich zone in the map - see software!


I don't know how much of the season you've got left, I presume from your header it's just a few weeks, I'd keep banging on with it as is, then whip the injectors out for cleaning and testing over the winter.

Then thoroughly and methodically work through the fuel system, cleaning out EVERYTHING (including the return hose), replace the fuel filters, flush the tank etc, then check the main sensors (MAP/ECT/TPS) to ensure they are within tolerance, then check the resistance / continuity of the loom for those sensors.

[prostar205]

Yes but those pictures look much worse than the ones you posted up last week. You keep saying "it runs fine", which is what keeps me heading towards the sensor readings. It might be worth buying the MEFIBurn software so you can see what the ECU is seeing and doing, it's great for diagnosing issues (logging, live readouts etc)

I can't remember seeing what sort of use you putting the boat though and whether you've given it a good blat, then turned off and checked the plugs etc, whether you have 20min idle to and from the ski zone or whether you can ski off the dock, all these things need to be considered when inspecting plugs. Are you chugging along fully laden surfing, no/full ballast and boarding or running 26/28/30/32/34/36 mph and course/free skiing - and at which point are you checking the plugs? - everything may be fine but you're just hitting a rich zone in the map - see software!


I don't know how much of the season you've got left, I presume from your header it's just a few weeks, I'd keep banging on with it as is, then whip the injectors out for cleaning and testing over the winter.

Then thoroughly and methodically work through the fuel system, cleaning out EVERYTHING (including the return hose), replace the fuel filters, flush the tank etc, then check the main sensors (MAP/ECT/TPS) to ensure they are within tolerance, then check the resistance / continuity of the loom for those sensors.

Those are the last pictures and each time I replace them and wait 5-7 hours and then pull them they are worse. But, yes - the boat runs fine. Does not cough or sputter. Starts right away.

I usually don't winterize until the end of Oct/early Nov. I use my boat to go to the University of Washington football games. Our stadium is 1 of 2 college football stadiums that are accessible via water. The other is the University of Tennessee. My plan is to run fuel injector cleaner in each tank of gas until the end of the season. Then over the winter pull the fuel rail and injectors and have them professionally cleaned and/or replaced.

[chrislandy]

I can't remember seeing what sort of use you putting the boat though and whether you've given it a good blat, then turned off and checked the plugs etc, whether you have 20min idle to and from the ski zone or whether you can ski off the dock, all these things need to be considered when inspecting plugs. Are you chugging along fully laden surfing, no/full ballast and boarding or running 26/28/30/32/34/36 mph and course/free skiing - and at which point are you checking the plugs? -
.

still no answer to this though

[prostar205]

still no answer to this though

For this summer, most (75%) of the 50 hours we've put on has been surfing. Carry about 3,000 lbs of water and passengers.

Not sure what "blat" means - must be a UK term.

During the months of Sept and Oct, the boat mainly see 20-25 mph runs from the marina to our football stadium on the lake. That is about a 30 minute run.

[curver900]

if it is only 5 of the 8 that are loaded up like that then I would tend to agree that it could be the injectors, but only if the other three look like they should, normal white/brown. If those other three are black and loaded up say 1/2 as bad then I would be inclined to believe it is either a temp issue (that sensor is cheap go buy one)or you have a mapping issue.

I am hearing myself, but this may be a trip to the dealer to have them plug in a computer and see what is going on and save you time and money....

[ValveCoverGasket]

yikes yeah those plugs dont look great!

have you thought about moving the injectors around that are on those holes and see if the richness follows?

if it is only 5 of the 8 that are loaded up like that then I would tend to agree that it could be the injectors, but only if the other three look like they should, normal white/brown.

agreed


and just for fun you could throw a new temp sensor at it - that one you posted the pic of on the last page. thatd be a shot in the dark and unlikely.
assuming the rest of your plugs are looking ok im still hanging my hat on the injectors.

[prostar205]

if it is only 5 of the 8 that are loaded up like that then I would tend to agree that it could be the injectors, but only if the other three look like they should, normal white/brown. If those other three are black and loaded up say 1/2 as bad then I would be inclined to believe it is either a temp issue (that sensor is cheap go buy one)or you have a mapping issue.

I am hearing myself, but this may be a trip to the dealer to have them plug in a computer and see what is going on and save you time and money....

The other 3 (cylinders 1, 7 & 8) are near perfect. No black soot or indication those cylinders are running rich. They look completely normal.

I had the dealer come to my marina and hook up the laptop back in last July. There were no codes at all.

[prostar205]

yikes yeah those plugs dont look great!

have you thought about moving the injectors around that are on those holes and see if the richness follows?



agreed


and just for fun you could throw a new temp sensor at it - that one you posted the pic of on the last page. thatd be a shot in the dark and unlikely.
assuming the rest of your plugs are looking ok im still hanging my hat on the injectors.

Removing the fuel rail doesn't look too bad. I just don't want to break any of the connectors. The entire engine and wiring harness is still covered in the original black paint from the Indmar factory. I'm afraid trying to take this thing apart will result in more damage to either a connector or the fuel rail.

As I have mentioned, the boat runs fine - just chews thru fuel and plugs. If I do take the fuel rail off to service the injectors, it will be a one time event as I don't want to keep doing it. I will take the injectors to a place local that specializes in cleaning them to factory new.

[ValveCoverGasket]

as mentioned earlier i think your setup is open loop - so there arent any o2 sensors to tell it something is wrong unless/until you see a misfire. youre running crazy rich, but not enough to misfire so code wise it oughta be happy as can be. that also is a hint that its not a coolant sensor issue, as is the other plugs looking fine.

so it must be something specific to those holes.
youve checked compression so its not a physical failure (again, if it was bad enough youd see a misfire)
unlikely to be spark related as that would likely be misfire inducing as well.
that just leaves you something specific to the fuel delivery on those holes, which can only be the injectors.

send stuff off to mr injector and call it a day

i can definitely understand being hesitant to remove that stuff more than once if you dont need to.
my hunch though is if you moved the injectors youd see the overly rich plugs move to follow those injectors.

[prostar205]

Yes, compression is solid at 160 +/_ 5 psi, if I remember.

Dr. Injector in Kirkland is who I will take the injectors too. They also run Kirkland transmission that rebuilt my Lightning swapped Expedition after 2nd and Overdrive mysteriously got hammered - probably a little too much right foot. They also did the trans in my 1969 Barracuda. They have always done a great job for me.

If its not the injectors, I'm back to square one but at least it runs.

[curver900]

The other 3 (cylinders 1, 7 & 8) are near perfect. No black soot or indication those cylinders are running rich. They look completely normal.

I had the dealer come to my marina and hook up the laptop back in last July. There were no codes at all.

I thought they could watch it while it was running and see issues not just look for codes?

I guess that sucks... i am with you then it is most likely those injectors...if you can move one and see if it follows then you do know your answer... and I would personally send them all in to be done...

[chrislandy]

For this summer, most (75%) of the 50 hours we've put on has been surfing. Carry about 3,000 lbs of water and passengers.

Not sure what "blat" means - must be a UK term.

During the months of Sept and Oct, the boat mainly see 20-25 mph runs from the marina to our football stadium on the lake. That is about a 30 minute run.

The technical definition of a "Blat" is: drive it like you stole it; Wide open throttle, full RPM to clear out the cobwebs

[ValveCoverGasket]

The technical definition of a "Blat" is: drive it like you stole it; Wide open throttle, full RPM to clear out the cobwebs

haha some sort of right-hand-drive italian tuneup??

[jpwhit]

I'm a huge proponent that the best diagnostic process is to come up with a hypothesis based on facts, then execute more tests or experiments to gather more facts. And then continue that process until you've isolated an exact failure. You should also pay close attention to facts that don't add up. This type of process becomes especially critical if you've gotten into the situation where you're dealing with multiple failures.

Some things to consider.

• If an injector is leaking badly enough to impact fuel consumption, then the engine will have a terrible idle. Leaks don't tend to change with engine RPM, so a big leak totally screws up the idle mixture
• Significant injector leaks continue to leak when you shut the engine off until the fuel rail pressure is zero. That will tend to flood those cylinders. This leads to issues with starting. You'll also tend to have raw fuel seep past the rings and make the oil smell like gas or raise the oil level.
• If your pressure is dropping after the pump shuts off, but then stops dropping at 18 psi, why does it stop dropping at 18 psi. Would a leaking injector stop leaking at 18 psi
• Connecting the boat to a computer is not just about checking for codes. There's a ton of other info available and actions that can be performed via a full feature diagnostics system. Even bad mechanics using a full featured diagnostic computer will do more than just read codes. I have the full blown commercial Rhinda Diacom suite of tools. I could tell you so much data if I had it connected to a running boat that it would make your head spin.

And if you think my post is saying it's not the injectors, then you missed the point. The problem very well may be the injectors. I'd be pretty surprised if the problem is only an injector issue.

[prostar205]

I'm a huge proponent that the best diagnostic process is to come up with a hypothesis based on facts, then execute more tests or experiments to gather more facts. And then continue that process until you've isolated an exact failure. You should also pay close attention to facts that don't add up. This type of process becomes especially critical if you've gotten into the situation where you're dealing with multiple failures.

Some things to consider.

• If an injector is leaking badly enough to impact fuel consumption, then the engine will have a terrible idle. Leaks don't tend to change with engine RPM, so a big leak totally screws up the idle mixture
• Significant injector leaks continue to leak when you shut the engine off until the fuel rail pressure is zero. That will tend to flood those cylinders. This leads to issues with starting. You'll also tend to have raw fuel seep past the rings and make the oil smell like gas or raise the oil level.
• If your pressure is dropping after the pump shuts off, but then stops dropping at 18 psi, why does it stop dropping at 18 psi. Would a leaking injector stop leaking at 18 psi
• Connecting the boat to a computer is not just about checking for codes. There's a ton of other info available and actions that can be performed via a full feature diagnostics system. Even bad mechanics using a full featured diagnostic computer will do more than just read codes. I have the full blown commercial Rhinda Diacom suite of tools. I could tell you so much data if I had it connected to a running boat that it would make your head spin.

And if you think my post is saying it's not the injectors, then you missed the point. The problem very well may be the injectors. I'd be pretty surprised if the problem is only an injector issue.

Thanks, I really do appreciate the input. You make complete sense with understanding the problem and then systematically attacking it. I also don't understand my my fuel pressure spikes to 60 psi and then almost immediately goes to 18 psi and stays there with the key on but the engine not running. Makes absolutely no sense.

However, the boat being 20 years old, replacing things like sensor, plug wires, coils, etc... makes sense to me even from just a preventative maintenance perspective. Cleaning the fuel rail and cleaning or replacing the injectors would fall into that category too.