Water in fuel sensor

[JMalik]

Upon changing my fuel filter and water-in-fuel sensor I ran into two problems with the sensor, Fleetguard part # 3831852 S. The connector would not mate with my 1996 Dodge Ram Diesel connector. Called Genoes Garage and they indicated the part was current and there was no alternate. It was necessary to remove the connector shroud leaving the retainer. I did so and the connector then mated.

The other problem was that the O ring seal leaked. I replaced the O ring seal with one of larger diameter which was more of a compression seal. I used a mirror and a flashlight to observe the valve with the engine running and I discovered a small jet of fuel squirting out from the valve/seal interfaces. I pulled the valve one more time and looked at the body and noticed mold lines were projecting out from the valve body. I measured the valve basic dimension diameter at 1.113 inches and the mold line diameter on the valve body at 1.138 inches. The projection of the mold lines was sufficient to prevent a seal between the valve and the filter housing. I cleaned up my old sensor, leveled its mold lines to assure a good seal, installed the sensor with the fleetguard O ring and it held.

I have run into this problem with a O ring seal on the check valve of my Trailer water pump. It would not seal until I leveled and polished the mold lines on the plastic body retaining the O ring. O ring seals need clean surfaces to seal against as they deform under pressure to form a seal. It's the pressure differential across the seal that seats the O ring to its sealing surfaces.

 

[Timd32]

My new one leaked on my 96, i took the o-ring off and used the one from the filter instead and it fixed it. I figure I screwed it up.

My connector was shot from some previous owner. I remade my connector with some Molex weather proof stuff I had.

 

[JMalik]

Mold Lines creating problems

 

[JMalik]

Wondering if I was an anomaly I searched the internet to see if other people had problems with the 12 valve water-in-fuel sensor. There were numerous examples and many solutions some viable and others not. One which was a clean solution was to replace the existing filter with one which eliminates the valve water-in-fuel sensor feature. It certainly solves the problem by removing the cause. Some of the replacement filters I found are as follows Fleetguard FF5219, NAPA 3395 and the Baldwin BF789.

The other approach is to refurbish the leaky water-in-fuel sensor. Fortunately my experience with the water pump check valve had resulted in a process for reworking plastic valve surfaces. By scraping or diamond filing the mold lines on the sealing surfaces of the valve body and flange to bring them back to the sealing surface level, then polishing them with 000 and 0000 ott steel wool a sealing surface can be re-established on the valve. After completing the refurbishing procedure I installed the valve on the fuel filter and there were no leaks.

 

[JMalik]

Regarding a change in connector. I have engaged both the original and the new water-in-fuel sensor connectors with the mating connector's shroud removed. I found that the original connector was very difficult to mate with the shroud on the connector. Once it was removed the connector was easily engaged by both the original and new connector. Leaving the retainer on the vehicle connector prevented connector separation, The shroud was an unnecessary feature which could be removed without compromising the connector.

 

[JMalik]

To remove the shroud I used this small side cutter.

 

[Timd32]

Yeah mine leaked at the large Oring to filter housing not the release valve. All I did was swap out the oring that came on it with the one in the filter, guess I got lucky on that part.

I looked back and mine is from Genos same part number but noticed its a different color then your so who knows could be slightly different material and the way it released from the mold just makes it a little more out of tolerance.

My truck side connector was very different as well, it was hacked up many times, but the one on my part I cut off is the same as what you show.

In my case for many years someone did not know to unplug the harness and looks like they were just spinning the harness with the filter.

Always fun digging in to some of these older trucks.

 

[JMalik]

My fun continues. After making several runs with the truck I noticed a fuel drip coming from the water-in-fuel valve again. I checked the valve to see where the leak came from and there was no leak at the O ring seal. Then I checked the valve exit and that was where the drip was coming from . So the basic valve itself is leaking. I then drained the filter using the drain valve and the drip stopped. So the valve itself is defective. Apparently the valve seat is also effected by the bad mold line. I will have to replace the valve.

 

[JMalik]

To verify the valve leak I used a Migyvac vacuumed pump and applied 20 inhg which is equal to 9.8 psi across the water-in-fuel sensor valve and it leaked down. I tried rotating the valve several times while pushing it in and then retesting the valve and it sealed with a low leak rate. Then I applied a sidewise push on the valve control and immediately the valve bled down. It appears that any misalignment of the valve actuator has a negative effect on its ability to seal. Rotation of the valve control could possibly relieve any alignment problems which occurred during assembly, shipping or installation. I verified the valve sensitivity to a sidewise force on my old valve and it also quickly leaked down with even a gentle sidewise push.

 

[BigPapa]

I had the valve fail on me three times. I finally found a Wix 33391 that doesn’t have the drain valve or WIF sensor. Here’s a thread from ‘08 about it. I think Shadrach had his numbers mixed up in his comparison. He cross referenced a Wix 33319. I’ve been running it for over 300K miles with no fuel injector or pump issues.

-Scott

https://www.turbodieselregister.com/threads/part-for-fuel-filter-without-drain.205348/

.

 

[JMalik]

Thanks for that input on millage without problems when eliminating the water-in-fuel sensor/valve. This is certainly a case for elimination of the sensor/valve. I was wondering if the sensor/valve was a residual left over from earlier times when fuel was of much lower quality than it is today. The other factor is that the 12 valve 2nd generation diesel has a far more robust fuel injection system than the current emission tuned diesels. Thanks for the other site with people experiencing 180k and 310k miles without draining any water out of their filter/water separator. I suspect that the decision of whether to remove or keep the water-in-fuel sensor/valve would depend whether the truck is living in the desert with typical humidity of 10% or in Florida with 50% to 100% humidity. The other factor is how often the truck is used and the fuel change cycle. Diesel fuel is hygroscopic meaning that it readily absorbs water in suspension and it can settle in a fuel tank and promote algae growth. The water in the fuel which has a low change cycle promotes corrosion of fuel system components. So the decision to keep or eliminate the fuel water separator and drain valve is largely depends on how and where the 12 valve diesel truck is used. At the same time it is important to keep the fuel tank filled to minimize the introduction of water in the fuel due to condensation as the fuel is subjected to temperature cycling regardless of what you do.