skman

I changed my fuel filter last week and when it came out it was black. There was no slime or sledge on it...just that the paper media had been dyed black.

I didn't think much of it at first. I didnt think it was algae because it wasn't slimy and I read somewhere on a forum where people were seeing this problem.

But the other night I was listening to a trucker's show on satellite radio and an owner called in and said he changed his filter and said he had changed his filter and it was black.
The radio host said it could be one of three things:

1. Algae..but because his filter wasnt coated or "slimy" it was not likely to be the cause.

2. Asphaltines (sp?) but it normally has a sticky feeling to the filter and the driver said it wasn't sticky or slimy.

3. Soot. The radio host said that soot could be bleeding by a leaky o-ring at an injector and getting soot into the fuel and therefore discoloring the filter.

I have never heard of the 3rd cause that he mentioned. Anyone have any experience with this? I've got warranty on my truck so if it was an injector, it would hopefully be covered. Could they see that by a pressure test?

Thanks

Sur5er

I don't see an O-ring in the equation or an injector causing this issue on a 3rd Gen. You would have a host of injector related problems. Take a fuel sample (before the filter) and send it out for analysis. Check with other guys that get fuel at the same place you do. I've seen many black fuel filters and all were algae related.

skman

Yeah, I haven't noticed any issues that would be injector related other than slow starting on winter mornings. Even on warm days it turns over 5 or 6 times before it fires. But my mileage seems normal for a 3500 and no smoke. Good power.

But wouldn't an algae issue cause problems like really slow starting, lack of power?

I was thinking as a preventative measure of throwing in some kind of anti-algae into the tank and have a couple extra filters ready.

Thanks for the reply. I'm new to diesels so I appreciate the feedback to learn from.

rockcrawler304

How many miles were on that filter?

I change mine at 10k miles and it is always a little black. I notice it is darker if I get several tanks of fuel from places that have a much slower turn over of fuel. If I get it from the Flying J (very high fuel turn over) the filter is just a very dark gray color. If you have no power issues, I say you are just fine and to make sure you change the filter at least every 10k miles. Even less if you want. Filters are cheap insurance!

Nascarcamper

That would be a long swim up stream, would of had to cause a fuel starvation while it was happening and plus it would be on the inside of the filter and not the outside.

Me think the host was sniffing soot!!

Guardrail

It's normal. Diesel is dirty, that's why we filter it. Change it every 200 miles if you want it cleaner, otherwise pop the new one in and go.

Guardrail

bonus

my first change mine was real dark. Follow up changes all dark, but not midnight. I would not worry,, seems to be working. change more frequently if you worried... get a Baldwin replacement.

MTC

I change mine every 8-10k and its always black....

Shorts

I changed min at 7k once to see, it was black. It's pretty normal.

madhat

I agree with the above.

Have you used any WMO?

PoorMansCat

Yep... if the filter is black... its just doing its job!!!. I would be scared if I pulled the filter and it was still while!!..

skman

Ok well thats good to know that it seems to be normal. It had about 10,000 miles on it according to the dealership.

I'm not sure what filter was in it before the change but I put a Balwin in when I changed it.

Never used any WMO before just some conditioners and gel preventatives.

Shorts...Thats exactly what mine looked like.

When I phoned the dealership, the guy called me back and I told him it was black and he said ... "Hmmm..thats weird"

But from what you guys have said it seems normal so I'm leaning towards him not knowing much.

Rednax

I change mine at every OCI. It's always dark (7-15k). When first purchased I changed it and that was the only time it was "black".

TedT

Change mine every 15k, always black.

Roadmedic

Mine is changed about every 20,000 miles.

It has always been black.

On my Ford when I ran it, it was the same miles and always black as well.