2004 Merc 5.0L MPI
Pulled about 2 gallons of water out of my tank a few weeks back. Boat ran great for a few trips and then started bogging again. Pulled out another half-gallon of water and replaced the o-ring in my gas cap. Haven't had any water in my separator since, but the boat still ran like crap and had just barely enough power to get up on step.
I got the good advice (thanks Don) that there is still water in the fuel system on the engine side of the separator. Messed around with it today and ended up getting about a cup of water out of the pressure-check schrade valve by the fuel rail (I removed the valve stem, put a hose on it, turned the key, used the run/off switch to make the HP pump run without starting the boat and then collected the liquid that came out). Within the first gallon of liquid, I got about 8 oz of water. The next gallon yielded only a few drops of water and just about all gas. Since the separator has had no water in it, can I safely assume that this water was pooled in the fuel cooler?
There was quite a bit of "gunk" in the water that came out. Seems abnormal to have gunk on the engine side of the filter/separator so I'm wondering if it formed on that side of the filter/separator? Is there another filter somewhere in that system after the separator? After the HP pump? After the fuel cooler?
The boat idled really smoothly for about 1/2 hour and would rev just fine, but when I left the slip and tried to run it, she started bogging WAY worse than before. It wouldn't go over about 2000 rpm (maybe 7-8 mph) and was backfiring when I tried to give ti throttle. After that it wouldn't even idle smooth any more. Back to the harbor.......
"Armchair experts" at the dock said
1. May have fouled the plugs by running water through it
2. May have fouled the injectors from running water/gunk through it
3. May have water still trapped in the fuel rail
4. May have another filter somewhere in there that is clogged
I can replace the plugs easy enough. But really, what are the chances that will be the fix.........
I don't know how to get any water out of the fuel rail. Is this fairly simple/straightforward? Anybody done it? Advice?
Is an injector cleaner likely to remedy clogged injectors or do they absolutely need pulled? Any advice on pulling the injectors?
Does anybody know if there is another filter in the high pressure end of the fuel system?
And this may sound like a stupid question, but what causes the backfiring?
Anything else I need to be thinking about???????
Thanks
Pulled about 2 gallons of water out of my tank a few weeks back. Boat ran great for a few trips and then started bogging again. Pulled out another half-gallon of water and replaced the o-ring in my gas cap. Haven't had any water in my separator since, but the boat still ran like crap and had just barely enough power to get up on step.
I got the good advice (thanks Don) that there is still water in the fuel system on the engine side of the separator. Messed around with it today and ended up getting about a cup of water out of the pressure-check schrade valve by the fuel rail (I removed the valve stem, put a hose on it, turned the key, used the run/off switch to make the HP pump run without starting the boat and then collected the liquid that came out). Within the first gallon of liquid, I got about 8 oz of water. The next gallon yielded only a few drops of water and just about all gas. Since the separator has had no water in it, can I safely assume that this water was pooled in the fuel cooler?
There was quite a bit of "gunk" in the water that came out. Seems abnormal to have gunk on the engine side of the filter/separator so I'm wondering if it formed on that side of the filter/separator? Is there another filter somewhere in that system after the separator? After the HP pump? After the fuel cooler?
The boat idled really smoothly for about 1/2 hour and would rev just fine, but when I left the slip and tried to run it, she started bogging WAY worse than before. It wouldn't go over about 2000 rpm (maybe 7-8 mph) and was backfiring when I tried to give ti throttle. After that it wouldn't even idle smooth any more. Back to the harbor.......
"Armchair experts" at the dock said
1. May have fouled the plugs by running water through it
2. May have fouled the injectors from running water/gunk through it
3. May have water still trapped in the fuel rail
4. May have another filter somewhere in there that is clogged
I can replace the plugs easy enough. But really, what are the chances that will be the fix.........
I don't know how to get any water out of the fuel rail. Is this fairly simple/straightforward? Anybody done it? Advice?
Is an injector cleaner likely to remedy clogged injectors or do they absolutely need pulled? Any advice on pulling the injectors?
Does anybody know if there is another filter in the high pressure end of the fuel system?
And this may sound like a stupid question, but what causes the backfiring?
Anything else I need to be thinking about???????
Thanks
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