Water in fuel alarm

[Connerkip]

About 50% of my cold starts, I get water in fuel alarm. I've checked the racor and fuel filter, drained, no water. I've cleaned the sensor and dried it, still no improvement. I bypass the alarm, and seem to get another warning stating failed sensor.

I never get the alarm under way or on warm starts.

Any thoughts? Perhaps I need to replace the sensor? I have the Volvo D6 370.

Thanks.

 

[Andrew Custis]

The alarm is reading from the on engine filter. Instead of unscrewing the filter itself, we recommend unscrewing the actual sensor from the bottom of the filter to verify that no water is showing up. If you have verified this way and the alarm is still present, I would try a new sensor.

 

[Connerkip]

Thanks Andrew,
First I checked the connector, cleaned, etc. Then I removed the sensor and drained half cup - no water. Cleaned and dried the sensor, reinstalled. I will change the sensor.

Does the warning shift to sensor inoperable when the water sensor is bypassed? I was wondering if something is compounding the issue.

 

[dclagett]

I had a similar problem however my water in fuel alarm came on after several hours of running. Always drained both filters never any water in fuel. Fuel looked excellent, no particles or cloudiness, just clear reddish pink liquid. Also let drained fuel sit for weeks to see if anything would settle out, nothing. Changed sensor still same problem. Finally changed both engine and external filters with only about 75 hours on them, problem went away. No water or particles found in the filters removed after I took them apart. The removed filters look very clean. My guess is there was something in the engine filter which triggered the alarm.

 

[knotflying]

Are you using fuel that has an additive like valvetec that is in the fuel you are getting from the marina? I had a similar problem shortly after I filled up at one. I verified that I had no water in the fuel, drained the filter and bowl and replaced the filter, same alarm. After speaking with a few people I was told that the valvetec has been know to create a false alarm. I ran out most of the fuel without the sensor connected and refueled without a fuel containing an additive. No issues since. This was two years ago.

 

[dclagett]

My water in fuel alarms started without the use of additives and just after the fuel filters were changed. I tried additives thinking there may be something in the fuel and an additive might help, however still had alarms. After having 6 or more alarms and draining the filters and not finding any water I tried another approach. When I received an alarm after running a few hours I would shut the engine down turning off the ignition which clears the alarm. Then I would restart the engine thinking if water is present I should get another alarm. No alarm. I could then run for hours without an alarm. Very frustrating. I talked to several diesel mechanics and did not get ideas of what could be causing the problem. I also took a sample of fuel I drained from the filters after receiving an alarm to a diesel engine class at Trawler Fest. I explained to the instructor the problem and he did not have any idea, however the instructor took the fuel sample from me and passed it around the class telling the participants this is what good diesel fuel should look like.

As I said before when the fuel filters were replaced again the problem went away. The only thing I can think of there was an issue with the original engine fuel filter that houses the water in fuel sensor.

 

[BB marine]

As I said before when the fuel filters were replaced again the problem went away. The only thing I can think of there was an issue with the original engine fuel filter that houses the water in fuel sensor.

I have to agree with you. I have never had this issue but I have read many post on Tug Nuts and other sites with the issue. No water in filter, Drain and then it comes back ,unplug the sensor, and plug it back in problem comes back. It sounds like when the filter is removed and replaced for the most part the problem goes away. It doesn't make sense but it seems to work. My new term for this is "bonafide mystery" a quote from another TugNut.Its easy enough fix ,cost about $40 for a new secondary filter. The only time it will suck is if it is the factory installed filter. I highly recommend anyone that has a factory installed secondary filter on the engine replace it ASAP when your on the hard or at the dock when your not having issues. Once you replace the first filter its easy to R&R the filter.

 

[koedding@comcast.net]

I had the exact same problem this past week. Only 100 hours on our C-26 D3 and it was serviced in the Fall by a certified Volvo Penta diesel dealer. We dry stack, so as soon as the water in the fuel indicator came on, we returned to the marina for a haul out. At the time, I didn't have anything to drain the water/fuel into. I since partially drained the filter the by unscrewing the sensor. Only diesel fuel was present with no signs of water. We'll see if this solves the problem when we launch next week. While I could "feel" the sensor to disconnect the cable and unscrew it, I was having a hard time with a funnel and bottle to drain into. I got some fuel that dripped into the bilge. I guess a narrow pan and an absorbent pad would be better. Any tips would be appreciated.

 

[Red Raven]

...While I could "feel" the sensor to disconnect the cable and unscrew it, I was having a hard time with a funnel and bottle to drain into. I got some fuel that dripped into the bilge. I guess a narrow pan and an absorbent pad would be better. Any tips would be appreciated.

I put a ziplock bag around the whole assembly then unscrew the sensor a bit while inside the bag to capture some fuel. Tighten it back up and then look for water in the fuel in the bag. I change the filter with the same method. The old filter goes straight into the bag. And is sealed up before it can spill.

 

[Eric R]

Count me in on this as well. Had the sensor failure alarm go off leaving the dock after a pump out. We had just come back from a 2+ hour run down the Potomac. Scared me when it happened, but no actual signs of an issue and it didn’t come back again.


Sent from my iPhone using Tapatalk Pro

 

[koedding@comcast.net]

Curt,
Ziplock bag! Nothing like applying the "KISS Principle"! Thanks for the tip.