Filthy fuel filter...what now?

I brought my '94 Econline van used and when she started sputtering, I gave her a tune up which turned out to be long overdue.



While changing the fuel filter, I noticed what could best be described as “hot chocolate” coming out one end. Well, I guess I found the reason for the sputter but my question is how to proceed from here?



I thought I’d fill 'er up and run a bottle of STP silver through the system(I hear that’s the best?). Then replace the filter again. What do you guys think?

You may have replaced the original fuel filter. I see no reason to replace it again until the next normal replacement interval comes along. Unless you enjoy replacing it, then, by all means, go ahead.

Everyone has their own “best” fuel system cleaner. My favorite is gasoline.

If you want the best fuel system cleaner, I recommend Chevron Techron. STP products are rarely the best–only the best-advertised.

You also might want to consider changing the fuel filter again in about 10k miles. I mention that because it is possible that what you observed coming out of the old filter was the result of rusting of the fuel tank. If you observe the same residue again, then you should think about replacing the tank.

I concur with the Chevron Gas cleaner. Much better then the STP cleaner.

I’d use the Chevron cleaner for 2-3 tank fulls.

And gasoline is a GREAT cleaner…to bad it’s NOT always clean itself. If it was there would be no need for cars to have filters.

If you want to be sure, drop the tank and have it cleaned, it is very suprising what you find in the tank after that many years. My idea is to get rid of the problem at the source, unless the material you saw was dissolved filter element material.

I can just about guarantee you that this van is going to suffer a fuel pump failure in the future. When a filter gets this bad the beating that the pump takes is much worse than the normal beating it gets.

If the van were mine, I’d drop the tank, clean it out, and consider a pump replacement as a preventative measure rather than risk being left on the side of the road.

Water vapor can condense in a tank, esp. on that is routinely only half full. If a van is left to sit for a year or more without running, and the condition of this one sounds like it may have been, varnish will also accumulate in the tank as the fuel breaks down and evaportates. Thus the sludge. The filter protected the lines and the rest of the fuel system, but I think you are right to replace it again after running a fuel treatment and a full tank of gas through it. It is cheap, easy to do, and cant hurt.

I forgot to say, having the fuel tank steam cleaned is a very good idea. No argument with that idea at all.

Update: When I removed the tank to replace the fuel pump, I drained it and found "mud’ in the bottom. I thought what the he!!. Then while flushing the inside with a spray hose, I discovered the problem. A dirt dobber (a hornet that builds its nest out of dirt) had nested inside the tank (probably as it sat dry before I had bought it) which began to dissolved every time I filled it with gas. There was larvea and dirt chunks as big as a quater falling out as I sprayed (see attached).

Oldschool was right. Dropping the tank was the right thing to do. Who would have thought this to be the problem! I would have been breaking down and changing filters every week. I also replaced the filter again just for good measure.

Runnng like a spooked rabbit ever since. Thanks guys!

Wow. That tank must have been dry a very long time, otherwise I’d think the gas fumes would kill, or at least drive away, any insect that was looking for a nesting spot. If it’s that dry, it makes me wonder about the condition of other hoses in the vehicle. You might want to inspect the brake lines just for peace of mind - wouldn’t surprise me if they’re ready to let go if the car sat long enough to completely dry the tank of gas fumes.

That’s absolutely the best follow-up report I’ve ever seen. Follow ups are rare as it is, so thanks for posting such a good one - complete with pics!

@shadowfox-I’m sure the tank was a replacement from a junkyard (where it acquired the new tennant) cause when I dropped it to replace the fuel pump, I noticed some of the brackets and fittings were, shall I say, less than factory spec.

@cigroller-No problem. This is just SOME of the debris. Can you make out the 3 larvae at the bottom?

Now you need to get rid of all rubber fleas, the leading cause of dry rot on tires… :wink: