Fuel filter light 7.3 PSD (1995)

[cjken]

Any one have experience with the fuel filter warning Light on a 7.3 PSD?
On a recent trip it started coming on intermittently. Engine never stalled or even missed a beat.
Want to trouble shoot before continuing my trip.
Got a new filter. Will install today. Wondering if it could be a in tank problem.
I’ve never pulled the sending unit.
If I have to I guess I’ll cut an access port in the floor. I’m not going to stop the tank with limited tools on The road.

Thanks

 

[Cav 3724]

There's a water sensor in the fuel filter/water separator. When water reaches a certain level, it makes contact across two poles and the light comes on. Look for a drain cock on the bottom of the fuel filter/separator. Open it and drain into a small bowl or the like. If you see water in the fuel (very distinct), you could very easily have water in the fuel tank as well.

 

[Cav 3724]

Get a diesel fuel additive that removes water from the fuel. Pour it in the tank. Definitely change the filter.

 

[Bikersmurf]

I don’t remember all the details, but some filters come attached to the lid. Beware, and be sure you get the correct filter.

I’d also recommend servicing the fuel bowl and replacing all it’s O-rings if you’ve not already done it. However, don’t do it till you’re back at home. DieselOrings.com sells a kit for about $7. I went with their more expensive $7 kit that had upgraded Orings that are rated for bio-fuel etc. It was about $2 more, but the cost difference was insignificant given the time involved. It’s one of those jobs you’ll never want to do... much less redo.

 

[cjken]

Thanks.
I did all the o-rings about 5 yrs ago
I’m going to pull the filter this evening and will give it a look over.

My truck has a separate indicator for water in fuel. One says “water in fuel” the one that is lighting up says “fuel filter”

I think that the light that I am seeing senses a fuel restriction. I’m hoping that it is just the filter Being a bit clogged up.
I hope to not have to mess with the sending unit if possible.

 

[cjken]

So filter was dirty

I drive over 600 miles with light intermittently on and made it.

Nw filter is in, no more light!

I’m guessing I’ll be good for the 1000 or so miles home.

I’m thinking my tank will need to be dropped and cleaned at some point.
That mess came from somewhere, but I think I can do that in the future.
I get another filter for the trip as insurance Incase this one clogs up.
Thanks for the help and advice everyone!!!

 

[hogasm]

No silver flakes.....tank ok

 

[Bikersmurf]

Two steps in the right direction.

By '97 I think the light was ditched.

 

[Cav 3724]

That is without a doubt the worst fuel filter I have ever seen. That gunk came from some place. Fuel tank cleaning in your future.

 

[ITTOG]

No silver flakes.....tank ok

He is referring to the filth. That much grime probably means sludge in the tank.

Sent from my Pixel XL using Tapatalk

 

[Cav 3724]

I have overheard people saying they have put used engine oil and ATF in fuel tank. Maybe ?

 

[IdaSHO]

That probably isnt from the tank.

Much more likely you have at least one bad injector O-ring, allowing oil to spill into the fuel system.

Best to do them all while you are in there. Id also consider glow plugs too.

 

[cjken]

That probably isnt from the tank.

Much more likely you have at least one bad injector O-ring, allowing oil to spill into the fuel system.

Best to do them all while you are in there. Id also consider glow plugs too.

Thank you for the o-ring advice I did not know that.

I checked the oil it’s been about 1000 miles since change. I filled up to the upper part of the hashed marks in the dip stick. Just checked and oil is still up to at least the middle of the hashed marks. So it does not seem to be using excessive amounts of oil.
That fuel filter has been in for about 30k miles.
I got truck with 45k now it has 77k

I think I will run the rest of my trip (about 1k more miles) then check filter again.

If orings were bad would it use more oil?
Or could it be just the beginning of Oring trouble?
I guess I’ll know more when I check filter again.

I’m going to carry an extra filter just in case the new one clogs up again.

Thanks for teaching me something new about the 7.3.

 

[Bikersmurf]

Didn’t know that could happen. ûyïI’m not sure exactly how, but I cannot even see all the plumbing to the fuel bowl... wrapping my mind around it would be another level of difficulty. 30k miles might be a bit long for a filter, but that’s something else.

Glad you’re back up and running.

 

[IdaSHO]

Thank you for the o-ring advice I did not know that.

I checked the oil it’s been about 1000 miles since change. I filled up to the upper part of the hashed marks in the dip stick. Just checked and oil is still up to at least the middle of the hashed marks. So it does not seem to be using excessive amounts of oil.
That fuel filter has been in for about 30k miles.
I got truck with 45k now it has 77k

I think I will run the rest of my trip (about 1k more miles) then check filter again.

If orings were bad would it use more oil?
Or could it be just the beginning of O-ring trouble?
I guess I’ll know more when I check filter again.

I’m going to carry an extra filter just in case the new one clogs up again.

Thanks for teaching me something new about the 7.3.

Fuel filter @ 30k isnt terrible, and by no means is oil in your filter normal.

When you did the injector O-rings, did you change oil filter at all? As you were doing the Orings, soon after? Not at all?
If you had changed the filter when doing the O-rings, and not since, the oil may very well be from the O-ring service itself.
best practice is to change the filter a few hundred miles after the O-ring service.

Oil consumption for the 7.3... remember, it takes 4 GALLONS of oil.
On my '96, by the time the oil is down to the middle of the hash marks, it is more than a half gallon low.
So if you are seeing that much loss in 1k miles, then yes... you are burning (or bleeding into the fuel system) a good bit of oil.

Your on the right track with the filter change.
Checking it and changing the filter out in another ~100 miles would be advised., and should tell you a lot more than our speculation