false water in fuel alarm - resolved!

gradytom

Seaman Apprentice
Joined
Jul 28, 2008
Messages
33
1998 Ficht 150's (yeah I can hear the groans) w/pinned heads, proper Champion plugs, they have been relatively trouble free and very strong, last compression test showed all w/in 5%.
Both engines start and run very well.
I buy my gas from the same vendor as usual, ethanol free, use XD50 oil and seafoam gas additive, 1 oz per gallon.
I started getting an intermittent check engine light/audible alarm on one motor only, code 37, "water in fuel sensor activation."
-Emptied the associated water seperator into a glass jar, no evidence of water or debris, reinstalled same filter.
-engine mounted seperator/fuel filter, no evidence of water, replaced w/new.
-fuel filter sensor test corerctly reads continuity when tested (new sensors show up as NA at my Evinrude dealer, and he's not much help).

The check light and alarm for one motor has been sounding intermittently.
Alarm sounds for 30 seconds, light comes on, sometimes the light will go out when I return to idle.
If I shut the motor down and turn off the battery for a minute or so, the soft code will clear as normal, sometimes it will come back, sometimes it won't. Always a code 37.
If I let the engine just idle for a while (20 minutes) it has not coded.
I ran the motor with the fuel/water sensor boot disconnected and the alarm sounded after a few minutes.
The motor continues to run as normal, no hesitation and no SLOW mode.
This is an air cooled ECM and I'm wondering if it's starting to flake out, maybe time to contact DFI.
Any advise you could lend would be greatly appreciated!
Thanks
Tom
 

boobie

Supreme Mariner
Joined
Nov 5, 2009
Messages
20,826
Re: false water in fuel alarm?

Re: false water in fuel alarm?

One thing I can think of from those "good old OMC days", they had some bad system check gauges/tachs that would give off false signals. If it wouldn't be to hard you may just want to swap them with other mtr and see what happens. By the way, DFI in Al is a good place. Delt with them a number of times.
 

ondarvr

Supreme Mariner
Joined
Apr 6, 2005
Messages
11,527
Re: false water in fuel alarm?

Re: false water in fuel alarm?

I can confirm the bad system check units, my 98 had two bad units, alarms on the first one, tach on the second one.
 

seahorse5

Rear Admiral
Joined
Jan 24, 2002
Messages
4,698
Re: false water in fuel alarm?

Re: false water in fuel alarm?

Some of the early SystemCheck gauges were troublesome. A swap with a known good gauge is the quickest troubleshooting technique.

If it's not that, then a wire is getting shorted or there is a glitch inside the ECU of the engine.

for ECU service -- www.dfitechnologies.com
 

gradytom

Seaman Apprentice
Joined
Jul 28, 2008
Messages
33
Re: false water in fuel alarm?

Re: false water in fuel alarm?

Thanks for the replies!
I will swap fuel water sensors from motor to motor next and recheck all my ground connections and see where it gets me.
Running with the sensor totally disconnected still sent a code 37 so it's probably the ECM.
Sounds like sending the ECM to DFI is probably going to be in my future, but with the relatively short summer here in Michigan I'm wondering if living with the intermittent alarm and check light for a while is problematic.
 

gradytom

Seaman Apprentice
Joined
Jul 28, 2008
Messages
33
Re: false water in fuel alarm?

Re: false water in fuel alarm?

Update -
After swapping fuel/water sensors, and emptying seperators again just to be sure the check engine light still come on intermittently.
I'm sending the ECU to DFI Technologies today, they say its a 3-4 day turnaround.
Spoke with them on the phone and they seemed to know exactly what
was going on from experience.
Hope this solves the issue and I can give an update with a resolution in a few days.
In troubleshooting the problem I found that fuel/water sensor assembly#0438644 is no longer available from my dealer. Mine tested fine but what would I do if I needed one . . is used one from a parted out motor my only option???
Thanks
gt
 

gradytom

Seaman Apprentice
Joined
Jul 28, 2008
Messages
33
Re: false water in fuel alarm?

Re: false water in fuel alarm?

Gotta give it up to the folks at DFI Technology!
Overnighted the ECU on Tuesday, they "tweaked" it, loaded new software and I had it back to me by Friday.
A few minutes of plug and play and we were off.
The motor behaves perfectly at all rpms, no alarms or codes, I could swear it even sounds a little smoother!
A great resolution to a perplexing problem.
Thanks DFI!
 
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