Fuel Tanks - Cleaning

[Fishin_Dan]

Went to take the boat out on Sunday... Launched it, and tied up to the jetty while parking the car (Mate was with it). Got into the boat, and went to start it... Flat battery! :-[

Used the second battery that runs the sounder, etc, and got the motor started... Excellent! All looking good (Plus some nice guy showed me how to pull start the motor!)

Motor idling nicely... then stopped. Damn! Motor didn't start again! DAMN!!! Primed the fuel line, and found that the bulb pressed in and stayed in... Only when I unclipped the line from the tank did it come out... Investigated everything I could, and the only thing I can think of is that the fuel tank has blocked up somewhere in between where the fuel first comes from the tank and where the fuel comes out of the tank into the fuel line (That has the bulb on it). It was just filled up with a full load of fuel, so the only thing I could think of was that there was some crap in either that tank of fuel, or the one before... The tank is pretty much brand new (Bought just before xmas), and the fuel line was bought about a month after that. The issue didn't seem to be in the line, but rather in the tank.

My question is how do I clean out the fuel tank? It is one of the red plastic fuel tanks (25lt). Is there anything I can do to help stop this in the future???

Everything else seems to be going well (For now!) but this fuel tank issue is going to be a major problem!!!!

PLEASE HELP! :'( :o

[skip2malou]

Have u taken the clips off where it connects the tank to the hose and checked if its clogged? That has happened to me, all I had to do was tap the clip a few times and all the crap came out. When I clean my tanks out I just hose them down with water and leave them to dry in the sun.

[Fishin_Dan]

It doesnt appear to be the line at all. As soon as I unclipped the hose from the tank, the bulb released straight away. This therefor points me to a blockage in the tank. But I am unsure how these tanks (I think its a 25lt Scepter) work. ie Where the fuel pickup is, how it transfers the fuel to the fuel line (External), etc. I would assume that it works on air pressure in that the bulb sucks some fuel in, and the air comes in via the vent, so pushes more fuel through, etc.... Just trying to work out where the blockage could be, and how I could resolve the issue.

I'm glad this happened to me at the ramp, and not out on the bay!

[blaze]

my thoughts are that its the valve on the tank outlet or the one one the hose end that plugs onto the tank, maybe when you are putting the hose onto the tank it is not unseating the valves, try pushing them in with a srcew driver
cheers
blaze

[Kerry]

Sounds like the tank is not venting air properly?

Cheers, Kerry.

[aido]

try disconnecting the line into the primer bulb and
blowing back into the tank. that might clear the
blockage temporarily in an emergency.
use caution though, you could get a gobfull of petrol, lol.

[NQCairns]

Here's a silly question - was the fuel line ie Bulb, connected around the right way ??? ::) ;D

[WAfarmer]

Screen on bottom of pickup blocked???

A G

[Fishin_Dan]

my thoughts are that its the valve on the tank outlet or the one one the hose end that plugs onto the tank, maybe when you are putting the hose onto the tank it is not unseating the valves, try pushing them in with a srcew driver
cheers
blaze

I took the whole lid (Where you fill the fuel) off to make sure the vent wasn't blocked, but this didn't resolve the issue.

I did push the valve in the motor end of the fuel line, but not the tank end. Will try that when I get a chance.

[Fishin_Dan]

try disconnecting the line into the primer bulb and
blowing back into the tank. that might clear the
blockage temporarily in an emergency.
use caution though, you could get a gobfull of petrol, lol.


Thats a good idea. Will try that soon.

Gob full of petrol is not the nicest thing around!!!

[Fishin_Dan]

Here's a silly question - was the fuel line ie Bulb, connected around the right way ??? ::) ;D

;D Yep. First thing I checked! ;D

[Fishin_Dan]

Screen on bottom of pickup blocked???

A G

AG - This is the sort of thing I was thinking it may be... I am not sure how the internals of the tank worked, so wasn't sure where it could be, but that's pretty much what I was thinking.

I am going to try to get a better diagnosis soon. Will take the clip off from the motor end (That clips onto the motor) and stick that end of hose into a bucket. Then prime the bulb, and see if any fuel comes out. Then do the same thing with an old fuel line. This will cancel out the fuel line being the issue.

If that still doesn't work, then it would seem to be a tank problem, and I will need to give it a really good clean out. Could this be just due to me leaving fuel sitting in the tank for a week or 2? I always empty it completely before refilling, but there are always tiny amounts that you can never get out. I would assume that this is where the garbage would site (as it's heavier than fuel)... I guess the tank should probably get a flush out after every use from now on....

[Fishin_Dan]

I guess the question is, will flushing the tank out with water be good enough? Or should I use metho or something else? Any info would be great.

[blaze]

Hi
If ya tank is only that old and its blocked because of crud in ya tank you must have put it in there, I have 2 plastic tanks that are probably 10 years old and never had any problems and they get thrown from boat to boat, sit in the shed getting crap all over them. takes a lot of crud to block a 1/4" pickup unless there is a floatie of some sort, check the valves
cheers
blaze

[Fishin_Dan]

Blaze - Will check all the valves as soon as I can. Unfortunately with work being as busy as it is, didn't get a chance last night....

The only way I can see crap getting into the tank is through the petrol containing the crap in it. I have only been using Caltex Vortex straight from the pump.

Does anyone run the petrol through a "filter" as they are filling up their tanks?

[Fishin_Dan]

Well, it seems that Blaze is the man! ;D

Bought an inline fuel filter yesterday on my way home from work, and fittied it into the fuel line last night after doing some troubleshooting....

I had an old fuel line in the garage which I connected onto the tank and took the tube off the motor side of the bulb. I then tried pumping the bulb to see if any fuel came through. A little did, but there was a lot of air getting in through the clip (It is really old and brittle, and doesn't seal properly). So checked out the valves on the new fuel line, and noticed that the round "pin" that should be there wasn't.... I also pulled the fule line out of the actual tank (After emptying all the fuel out). The mesh on the pickup was clean (no crap), so put it all back together, and gave the whole tank a good hose out and set aside to dry.

I then noticed that there was a little air getting in where the OMC male fitting is screwed into the tank. It seems that it wasn't put in completely straight, so was letting air in. I also figured out that the little pin on the post of the male fitting needs to be pressed in to let air through (when I was blowing air into the fitting). And as the valve pin on the female connector wasn't there, this would be why no fuel was coming out!

So off to the chandlery today to get a new female connector and a "sealer" that is fuel resistant to seal up around the male fitting and the actual tank.


Well hopefully this should resolve all the issues. Will have to take it out this weekend for a run (And a fish - how convenient! ;D ). I feel a little more comfortable knowing that the fuel filter is installed too. It had been something I had meant to do, but hadn't gotten around to. The other advantage of the inline filter is that I can visually see if fuel is coming out of the tank at any stage too!

Thanks everyone for all your info.

[blaze]

Hi Dan
Most of the time its a matter of sitting down and slowly nutting ya way through how things work and the answer will be there, insaying that even the best will get stumped sometimes and more often than not its because they overlooked the obvius.
cheers
blaze

[Fishin_Dan]

Yep. Seems to be the case here mate. I knew what was going on, I just didn't have the knowledge to find out exactly where it was happening. Once I had the chance to sit down and go through it all and play with it, it all fell in to place.

Of course all the advice from everyone certainly helped as well.... ;D

Thanks again Blaze!

[Kerry]

Outboards really should have an additional filter/water separator before the motor filter more so then just a filter especially the water separating part.

Cheers, Kerry.