Whatbs the crud

"Today I drained my Racor filt

"Today I drained my Racor filter and got about 1/4 thimble full of crud. It is the color of rust, but when you roll it between your fingers, it's not gritty, but somewhat slimmy. Anyone know what that stuff is and why it's in the gas?"

"It is dead or alive algae, di

"It is dead or alive algae, dirt and other crap that is in diesel fuel. It is a good idea to treat your fuel with algaecide on a regular bases. If you have never done it , it would be a good idea to clean the tank and lines soon after treating as the algae will block fuel lines. It will also plug up your Racor prematurely especially in rough weather when the fuel tank is stirred up."

"If its gasoline and you have

"If its gasoline and you have been introduced to ethanol in it, its probably the junk that's been dormant in your tank that the ethanol has 'liberated'. It has a cleansing effect on fuel systems.

Keep a couple extra filters on the boat and start checking them regularly. The more you use it, the faster that junk will be removed."

Makomark - I've been runni

Makomark - I've been running 80 to 90 gallons through that tank each week since mid-June. Figured it ought to all be cleaned out by now.

Just would like to know exactly what that crude is so I can counter it.

"WD:

I wouldn't think t

"WD:

I wouldn't think that a 1/4 of a thimble is enough to worry about, especially as long as the engine runs 'normally'.

The other thing to remember is that the source may not be your tank, but somebody further up in the supply system. Depending upon the how many players and pieces of gear are involved, it may take a while longer. Lots of variables here....

If you buy consistently from one source, you could provide them a sample and ask them to push the "what's is this?" upstream.

If it keeps recurring, and you can't get an answer from the supplier(s), you could always get an "environmental lab" to do a chemical ID on it. May be a few bucks but could be money well spent."

"Makomark - good suggestions.

"Makomark - good suggestions. Didn't save it this time, but will do so the next time, and push it up the chain. Think everyone would like to know exactly what that stuff is.

Dwight may have been correct that it could be the remains of algea or bacteria that grew in water the ethanol separated out, but likely further upstream since I'm running through so much gas from my tank."

"I've seen that algea stuf

"I've seen that algea stuff he's referring to , but never in a gas tank, just oil tanks. Yes, it is really nasty...

I think the way things are going, we're all gonna trade in our little 'spin-on' racors for something more diesel sized....12-14" tall, 8-10" in diameter, same flow rate - with filtering area measured in square yards, not sq inches."

"I was referring to diesel. So

"I was referring to diesel. Some people use the term gas for all fuel similar to how Texans call all pop, coke even if it is root beer. Most of the questions I get are related to diesel engines.
I have never seen algae in gas, but I have seen ferrous oxide which would look like what you have described. It can come from the storage tanks that a supplier is using and in some cases I have seen it in the sediment bowl from water in the gas corroding the medal of a sediment bowl. Cleaning your tank may be in order. I have gotten into a habit of putting a sample of the fuel that I am going to put on board into a glass container and let it settle to see how clean it is before refueling."

"Pushing it upstream isn't

"Pushing it upstream isn't going to help. They're going to walk you over to their filter and show you that they already filter the fuel right before it goes into the hose. The stuff you're seeing is probably pieces of rust from your tank, some condensation from when it sat for a few months with a less than full tank, and some other misc reasons including the more aggresive cleaning action of ethanol in the fuel. That amount and kind of stuff is the reason you have a fuel filter. It's doing exactly what it's supposed to. Drain it out every so often and enjoy boating.

K"

"Fred - It's not rust alth

"Fred - It's not rust although it has the same color. Not gritty, but slimy. Has no magnetic properties. Not likely my tank since it's all aluminum and was steam cleaned in 2006. Running mucho fuel through it on a weekly basis - 80 to 90 gallons a week. Boat sits on a lift in front of my house and gets multiple runs every week from early April through late November. Winter storage is always with a completely topped off tank treated with either marine Stabil or Startron (previously) and ValvTec this year.

My issue is that I want to determine what it is so I can counter it. Will pay the bucks for a lab analysis and report back.

BTW - I grew up in a service station. Those pump filters catch only the big stuff because of the need for fast flow through."

"Please be sure to tell us wha

"Please be sure to tell us what the lab says. Sounds very normal to me.

The service station filter is a 10 micron filter. That's not very big stuff. If you're buying from a branded station they will check that you service that on a regular basis. They don't want anything getting into their customers tanks either. I owned service stations for a number of years and have had this conversation more than once. Accusations of water in the fuel are a total nightmare. Service stations and fuel distributors take great pains to keep the fuel being dispensed clean.

Other things to think about, since you keep you boat in the water. Did you ever refuel from a portable can? Did someone ever possibly leave the fuel cap loose? Have you changed the o-ring on your fuel cap lately? Does your boat get warm during the day then cool at night around moist air?

Now I know you've written me off as a supplier appologist, but you keep telling us how much fuel you're running thru and have found only 1/4 of a thimble full of "stuff" that your filter caught?

At 80 gallons a week since June, you've burned 800 gallons of gas. 800 gallons, times 20 MPG and you've used way more gas in 2 1/2 months than the average car does in a year. And yet you only found 1/4 of a thimble of crud in all that fuel?

Al Gore's not going to like your carbon footprint!!!

Enjoy the boat, don't sweat the small stuff. I've been out for a little more than 4 weeks now. 2 1/2 weeks to go and I've burned 103 gallons of diesel in 342 nautical miles. I've still got 297 gallons on board in reserve. I'll bet there's more than a thimblefull of crud in there somewhere. The filters will grab it for me.

K"

"Folks - thanks for all your u

"Folks - thanks for all your useful comments. The CRUD turned out to be about 60% rust. The remainder was a soup of various stuff not identified. Very fine rust particles. The reason it fooled me (and my magnet) is that it was embedded in some sort of algae. That’s what gave it the slimy feeling. I’ve concluded that either my tank was not cleaned as well as represented, or that there is some fine stuff getting through from the pump filter, but getting caught by the Racor filter. I will continue to monitor."

Thanks for the update. I hope

Thanks for the update. I hope everything is still running well as we head into the last of the summer boating season.

K

"ditto fred's "thanks&

"ditto fred's "thanks"...kind of curious where the algae originated now....another by-product of ethanol, maybe?"