Water in fuel warning

[julians]

So, i had time to trace the fuel line plumbing today, the fuel line goes from the tank,to the pre filter mounted on the bulkhead and then on to the engine mounted filter,so thats all as it should be.

So, i dont know why there was no water in the pre filter when there was water in the engine filter.

Never mind though,the issues hasnt appeared since so im hoping all is good.

I have a new problem now, looks like the gear shift actuator is on the way out, when changing to neutral today, the evc emitted a loud beep and wouldnt go back into gear, turning off and on again fixed the issue. It did this once last year and it was presumed to be a sticky shift cable,so that was replaced over winter, but that doesnt seem to have fixed the issue so im guessing itll be the much more expensive actuator at fault.

 

[Montemar]

Did your last batch of fuel have water in it?

 

[aquatom]

I would want to know why there was no water in the prefilter. How much did you drain off? Are you sure what you drained was fuel not just did coloured water?

 

[julians]

I would want to know why there was no water in the prefilter. How much did you drain off? Are you sure what you drained was fuel not just did coloured water?

I drained about half a litre out of the pre filter, Im pretty sure it was pure fuel, it wasnt discoloured or dark in any way. It was a yellow/blue colour,very clear,no cloudiness.

What does water contaminated diesel look like? I was expecting brown/cloudy liquid.

 

[julians]

So,i had another water in fuel warning today.,so idrained the pre filter and engine filter completely, but couldnt see any obvious evidence of water in either of them,it just looked like clean diesel came out of both.

Is it possible for there to be water in the fuel,but the fuel still looks ok?

Engine is running fine with no obvious issues.

Could these be false alarms? How do the sensors work? Are they known to fail? Is there a way of testing the sensor?

 

[Portofino]

Basic Principle
The operation of the sensor is based on the resistive measurement method. Water is detected because it has a lower resistance than diesel fuel. Measurement of fluid resistance is performed between the two electrodes (for sensor options with two electrodes), or between an electrode and a ground (for option with single electrode).


They are either faulty
V sensitive ie there's a tiny amount of water and it's getting detected
But you say you found real "water "recently ? Assuming that's correct ie you not going mad -that sounds like you have a dose of dogey fuel .
Startron reckons to disperse water ( from condensation etc ) into the fuel to burn off .

On that vien have you added anything to change the "resistance " ---now - detected by v sensitive kit

Does your VP EVC set up or what ever it's called show sensor errors like MAN MMDS ?
That would be nice ,cos if that's not alarming then the sensor is true .

 

[julians]

The first time I drained the filter the other day I thought I saw clear water drain out, but now I'm doubting myself , it could just have equally been nice very nearly clear diesel, given that I didn't find anything nasty in the pre filter.

Today when I drained both filters there was no water, just nice clear diesel in both.

On both occasions the water in fuel light went out after I had drained the filters.

Maybe I need to see if the light goes on/off if I wiggle the connectors or simple turn the engine off an on again. I'll have a close look at the wiring tomorrow and see if I can see any issues.

 

[julians]

So, today the wif light came on again,but then a few minutes later went out and stayed out for the remainder of the short trip. I left the engine idling whilst i washed the boat down,and the light didnt come back on.

I have not drained the filters yet, but if its like last time the stuff that comes out will look like nice clear diesel.

How sensitive are the wif sensors typically? Can they detect a level of water that is not obviously visible to the naked eye? Or would it be obvious that there is water present when draining the filters.

Im still not sure if i have a real issue or just a malfunctioning sensor . I did clean the sensor and electrical connectors with contact cleaner,but it all looked clean to start with.

Flying back to uk tomorrow,so next time to inspect will be october.

Im erring on the side of sensor failure,but dont want to rule out having some water in there.

 

[julians]

So,just to close this thread off, and for anyone else in future with similar symptoms.

I came back to the boat in october after a few weeks back in the uk, the water in fuel warning light was still blinking away, so this time i drained the fuel in the filter into a clean clear container so i could decide for certain whether it was false alarm or genuine water in fuel. Anyway, once drained into the clear container and left to stand for a while, the fuel was perfect with absolutely no trace of water.

And this time on restart of the engine the water in fuel light was flashing away again immediately,then later on it stopped flashing,then a few hours latwr started flashing again. At this point im pretty certain its just a failing sensor.

After a bit of googling it seems that the vp d4 engine uses the same water in fuel sensor as the td5 engine used in land rover discoverys, and on the land rover forum a lot of people complain that this sensor fails and gives false alarms.

So ive ordered a new sensor (£20 for land rover sensor vs £90 for vp sensor) and am pretty sure this will fix the problem.

 

[julians]

Final update - i bought the land rover sensor as mentioned in a lot of online forums, the lr sensor appears identical, fits perfectly, but must use a different resistance range as the one i bought throws a sensor fault.so i bought an official vp sensor and that has fixed the issue.