Best way to clear debris in fuel tank?

[Jcolman]

I think I have something in my fuel tank that is clogging the fuel intake on my Perkins. I was out on the boat this morning running about 2000 rpm. The motor was purring along just fine. I ran it for about 15 minutes at 2000 rpm until I cleared the channel. I then pushed it to a little above 3000 rpm. After a minute or so at the higher rpm, the motor died....no sputtering, it just quit like I had pulled the shut off valve. The motor restated just fine and continued to run flawlessly at 2000 rpm or lower.

This is the second time the motor has quit on me unexpectedly.

What I believe is happening is that there is something in the fuel tank that got sucked up into the fuel intake when the motor started pumping more fuel at 3000rpm, starving the motor. When the motor died, the debris fell back to the bottom of the tank.

What I'm thinking of doing is to run most of the fuel out of the tank (I have about 8 gallons or so left in the tank) then unscrew the fuel pickup tube and remove it. My idea is to get another pump, maybe a hand held or a cheap bilge pump, attach a long flexible tube to it, and start pumping out the bottom of the tank. I'll pump the remaining fuel into a portable tank but with a strainer of some sort to catch any debris. Hopefully, whatever is clogging my fuel line will either get sucked up by the pump, or get wedged in the intake of the tube and I can simply pull the tube out with the debris on the end.

Does this make sense to you guys? I'm looking for the easiest way to clean out the tank without removing it from the boat.

[Nicholson58]

Do you have a fuel filter between your tank and engine? On the engine? If not, get one, preferably with a water separator.

You can have a fuel polishing service contract to clean your fuel although, 8 gallons is hardly worth the effort. Do you have an inspection port on the tank? If you can get inside you may find it full of sludge especially if its old. Water and diesel make yuck and worse if algae gets involved. If you can suck from the bottom most part of the tank you may find water. The dip tube is normally located a couple inches above the lowest point to avoid water.

[Jcolman]

I do have a fuel filter and water separator. No inspection port. The tank was installed in 09' I believe. I agree that polishing 8 or 9 gallons is rather pointless. I'll add some "killz" to the fuel next time I'm at the boat to take care of any growth in the tank but I still need to figure out how to clean out the tank.

[shorebird]

I used a high flow fuel pump to circulate and recirculate the fuel while running it through a filter. In the end I just disposed of all the fuel and gunk, then added fresh fuel. I used a Fillrite brand pump mounted in a plastic tote (to catch any stray fuel.) I also used an elbow fitting at the end of the hose so the fuel would be pumped in a horizontal direction for maximum agitation.

[AnchorageGuy]

Your only real option, if the filters are clean, is to have a service come in with the right equipment and try to clean the tank. A small pump isn't going to do anything. Without some kind of inspection port, this is going to be next to impossible, this time and any time in the future. You might seriously consider adding an inspection port and having the tank cleaned at the same time. Since you say the tank is from '09, this may not be an issue, but in older tanks they put a screen in the bottom of the pickup tube that always clogged. Chuck

[Nicholson58]

J - Your idea of using a pump and a "thief" to the bottom of the tank and as shorebird suggested is a good plan. Pump the stuff into a clear jug and let it settle you might verify the water & other stuff from your tank. I have done this and use glass jugs so I could see the contents well. Water, algae, black slimy stuff and bugs. (some large bugs).

[Cap Erict3]

Originally Posted by Jcolman

I ran it for about 15 minutes at 2000 rpm until I cleared the channel. I then pushed it to a little above 3000 rpm. After a minute or so at the higher rpm, the motor died....no sputtering, it just quit like I had pulled the shut off valve. The motor restated just fine and continued to run flawlessly at 2000 rpm or lower.

Adding a shut off valve would let you test your theory.

I don't think that is your problem. Closing off your fuel at the tank would cause it to sputter and die.


Sent from my iPad using Tapatalk

[OceansFive]

I had the same thing happen to me when I bought Kuan Yin. The primary ( off engine) fuel filter was being clogged by filthy fuel. Go ahead and drain your tank, hoses, primary filter, secondary filter, being careful NOT to allow any more fuel to pass to the injection pump.

Flush the tank with clean fuel until it comes out 100% clean. If you have access inside the tank wipe it spotless with diapers.

What is the fuel tank made of? Anything than can degrade? How long was the fuel sitting?

Save yourself a lot of potential future trouble and invest in a larger primary fuel filter - bigger than you strictly need for fuel flow so that you have some "spare" filter capacity if it begins to get blocked again. Get a filter with a see- through portion so that you can see the fuel and see any water collecting.

Racor filters can be fitted with a vacuum gauge so that you can see if the filter is starting to plug. Regular checking and entry in your maintenance log will allow you to see if the pump is sucking harder than usual over time.

Remember that humans can only see down to 40 microns. The primary filter needs to be a maximum of 10 microns and the secondary filter ( on the engine) a maximum of 2 microns. A filter that looks clean may in fact be completely clogged.

Depending in what you find and your system, it may be prudent to add biocide to your fuel each time you fill.

Let us know how you get on. Good luck.
Den

[Hud3]

If you do go with the pump option, I'd suggest using an appropriate length of copper tubing attached to the pump's intake tubing for probing the tank. The stiff copper will be easier to direct around the inside of the tank than flexible tubing.

[Jcolman]

Originally Posted by Cap Erict3

Adding a shut off valve would let you test your theory.

I don't think that is your problem. Closing off your fuel at the tank would cause it to sputter and die.


Sent from my iPad using Tapatalk

So what else would cause a motor to just up and quit then restart? It was flat calm when I was running and the motor didn't overheat or do anything out of the norm that I could tell.

[Jcolman]

I found a company that cleans fuel tanks so I'm having them service my boat for me. I'll also change out the filters and start with fresh fuel. Hopefully that will fix my issues.

[AnchorageGuy]

Originally Posted by Jcolman

So what else would cause a motor to just up and quit then restart? It was flat calm when I was running and the motor didn't overheat or do anything out of the norm that I could tell.

There are actually a few things that can cause this that has nothing to do with the tank. I would suggest you first get a clean 5 gallon diesel jug, secure it in the boat and stick the fuel line in the jug. Go run the boat for a while with someone standing by to assist if needed. If the boat runs fine, clean the tank. If it stops running, three things will cause this. 1. you have a fuel blockage somewhere else. B. the fuel system is sucking air from somewhere or 3. there is a problem with the injector pump. Chuck

[Jcolman]

Originally Posted by AnchorageGuy

There are actually a few things that can cause this that has nothing to do with the tank. I would suggest you first get a clean 5 gallon diesel jug, secure it in the boat and stick the fuel line in the jug. Go run the boat for a while with someone standing by to assist if needed. If the boat runs fine, clean the tank. If it stops running, three things will cause this. 1. you have a fuel blockage somewhere else. B. the fuel system is sucking air from somewhere or 3. there is a problem with the injector pump. Chuck

Thanks Chuck. According to the guy who's going to clean my tank, my problem could also be a dirty filter. He said that sometimes a filter will allow enough fuel to run at low rpms, but stall out at higher rpms because the motor cannot get enough fuel.

Since I don't know how long the fuel in my tank has been sitting or what kind of maintenance the PO did or did not do, I'm not taking any chances. I'm doing a top to bottom clean out of the fuel tank and filters.

[MarkJ]

Before you go waste money!


I had the same problem.






This whole old gasket must have fallen into the tank on a previous repair and had got itself right up the fuel pickup!
So before you polish the fuel pull your pickup out and see if you can blow through it - tastes great

Mine was clogged up with the gasket and then crap had impacted around it.

Easy fix

[Jcolman]

Originally Posted by MarkJ

Before you go waste money!


I had the same problem.






This whole old gasket must have fallen into the tank on a previous repair and had got itself right up the fuel pickup!
So before you polish the fuel pull your pickup out and see if you can blow through it - tastes great

Mine was clogged up with the gasket and then crap had impacted around it.

Easy fix

How did you get the old gasket out? Inspection port?