Trouble filling up at servo

[Jono_SS]

Hello.

I'm having trouble fueling up at the servo - fuel comes spurting back out the rear filler, even if the tank is only half full. This happens even when I have the fuel trickling in. It is getting quite frustrating, and seems to have gotten worse. The weekend before last, I ended up going from servo to servo putting in a few litres then giving it a chance to settle into the tank. I ended up borrowing a jerry can from a mate and taking that with me 'cause it was so frustrating.

Are there obvious things I should look for i.e. traps for young players? I know there are front and rear breather hoses. Can they get blocked? How do you check?

cheers.

Jono.

[Dignity]

Jono,
Check your overflow vent in case ants/wasps have decide to build in there. Also check the lines themselves, if they are old they can deteriorate and pieces will come loose internally and cause a problem although I would think the pressure from incoming fuel should fix it, if in doubt replace them, cheap to do.

In my case an internal baffle plate had come loose in the tank and was jammed up near the intake side. Not sure how you would fix something like that but in my case I drained all the fuel out (cow of a job when you have over 150 litres in there) took the tank out and shook it around poured clean fuel through it at every angke I could and put it back. Seems to have fixed the major problem. I also buy fuel in jerry cans when the price is right and fill the boat as it saves on having to drag the boat into the servo.

Is pulling your tank out an option?

[mitch92]

Check breathers for blockages...give them a blow

Check they do not have low spots, if it droops down to low, or has a loop that may fill with fuel, then it may become blocked. If this is the case, remove the loop/low spot

[Jono_SS]

Thanks guys, I will go and check what you have suggested. I know the breather hoses do have loops in them up in the transome, so I'll see if there is fuel stuck in there. However, I don't fancy putting my lips anywhere near the hoses (I get flashbacks to a fuel siphoning episode that went wrong in my youth)!

I could probably pull the tank out if necessary, but I'm definitely hoping for an easier outcome.

cheers.

Jono.

[thylacene]

Thanks guys, I will go and check what you have suggested. I know the breather hoses do have loops in them up in the transome, so I'll see if there is fuel stuck in there. However, I don't fancy putting my lips anywhere near the hoses (I get flashbacks to a fuel siphoning episode that went wrong in my youth)!

I could probably pull the tank out if necessary, but I'm definitely hoping for an easier outcome.

cheers.

Jono.

For my money, the loops in the breathers are the culprit. If you fill the tank to full the fuel in the breather will match the height of the fuel in the filler hose, mounted on the gunnels? and fuel remains in the loops until next time you fill, as smal movements of air due to temperature fluctuations result in bubbles being forced or drawn through the loop.

If you fill at any reasonable rate, the filler hose will fill with fuel creating hydraulic pressure in the tank, only a couple of psi, but with fuel entering at better than 10 litres per minute, the same amount of air is then expelled thru the breather, which being smaller has a higher rate of velocity, causing the fuel in the loop to be blown out with the escaping air. Every time you "trickle fill" you will end up with more fuel in the loops.

I had exactly the same issue, I drained the loops and now take care to not fill to fast, and to only put in the fuel stated as being used by the engine interface. Not everyone has this luxury. If you hear the fuel coming up the filler hose when you are filling you need to slow the rate of flow and stop before it reaches the equivalent height of the breather. I have only experienced it once since going through the exercise due to some very rough seas with a full tank.

I will also admit to giving the breather some "CPR" by blowing through it from the outside before I filled the next time, that moved enough of the fuel in the loop to avoid it going everywhere when I filled it next, and at a slow rate.

Hope this helps

Thy

[NAGG]

Same issue with my Hornet - Its a shocker ....... You can get fuel coming out a the filler point or the overflow ....... but can add another 15 lts
The only options are to trickle feed ...... which takes ages or use gerry cans

I've started to use the cans .......... which doesn't bother me really

Yes the overflow hose / vent is too small.

Chris

[Moffy]

Not an easy fix - but if you are going to the trouble of taking the tank out - consider putting a second filler in (on the other side to the existing one) - open both fillers when you fill up and you won't have this problem - added benefit of it no longer mattering which side of the bowser you pull up at.

Hooker boats do this as standard - only know this as my brother has recently ordered one - I thought it was a brilliant easy solution to a problem that just about every trailer boat with an underfloor tank has at one time or other - and for really very little extra cost (at the time of building). (am sure other builders may do it as well - but hadn't heard of it before).

Again - not an easy or quick solution if retrofitting it - but might be an option if you can't otherwise solve the problem (and are taking the tank out anyway).

Moffy

[Timfishin4fun]

Try this for an easy fix.

Use a length of hose down youf filler to be in the tank but not in the fuel. Make this long enough to hang over boat incase of fuel coming back out.

Fill tank with bowser. All you have done is created another temp breather.

Remove hose and clean off and store for next time.

Tim

[samson]

get this problem too it seems to be fuel in the breather lines or an air block in the tank and is worse the hotter the day is but if you blow out the blockage of air with fuel it fills fine or as other guys have said use jerrys and you don't get the problem as there isn't a air mix with the fuel.

[stue2]

Had the same trouble on my old boat. The breather came out the side and ran horizontal for about 10 cm. Had to put an elbow in there and re rout the hose so it only ran up hill. An extra breather was needed but managed with the elbow and hose adjustments.

Cheers Stu

[Dignity]

Guys I am having a rethink on my original issue (as distinct from Jono's) and I don't have any loops in my breather hose. As the baffle plate was easily fixed although only temporarily I was wondering if a second breather installed from a tee off from the tank would actually ease the situation as filling is still slow at the bowser. I might try it and take it down to the bowser to give it a go when I can finally get back home, or am I barking up at the wrong tree.

If the vaffle plate gives me problems in the future I will take opportunity to remove the tank and have modifications made to the breather as well as the filler side as the current configuration wastes a lot of my kill tank space.

Jono, have you had any success with any of the above suggestions.

BTW - on a previous vessel I had a build up of crap on the inside of the breather vent which caused me problems, seems that the double filler tube must be the techncal solution which seems overkill for a little plastic tube problem.

[Chimo]

Easy fix is to drop the front of the the boat when you fill, ie lower the front of the trailer.

It is the only way to get a totally full tank on the Vagabond and I'm sure it applies to many other boats.

The Vag has two breathers and while filling slowly helps and reduces blowbacks the dropped bow was the only failsafe solution this GOM has found so far ( in 45yrs of boating)

Cheers
Chimo

[Smithy]

I had a similar but not the same problem with the Stabi. With a bit of heat it seems to pressurise the tank and then dribbles out my breather. I bought about 5m of the re-inforced clear hose and coiled it about 10 times with a cable tie then connected it to by breather. Helped a bit as that 5m of line takes up a lot of fuel and each coil is a little air lock. Mine fills up like a ripper though so can't help you Jono. If you do pull the tank out, I would suggest getting a cap welded straight in the top of the tank if you have a removable centre section to your floor and easy access. That is the way to go to jam heaps of fuel in and also handy when you are in the boat to put a dipstick in. Top the tank off through the filler once you are 99% full.

[stue2]

A mate had the same trouble as you did Smithy but it lifted the coating off the paint job on their brand spanking Surtees

Chimo, one of the servo's i use has a slight slope one way so I always face down hill as you suggest. dont have any trouble filling, gets a bit messy when you find out its full.

Cheers, Stu

[BILLY THE KID]

this happens abit on my 4WD aswell , i just turn the fuel pump nozzle upside down or on a 45 deg angle and it seems to fix the problem