Longranger fuel tank not breathing
Submitted: Wednesday, Jun 10, 2009 at 12:22
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69679
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Replies:
8
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Gossy
Hi all,
I have a longranger fuel tank on my LWB GQ nissan patrol (2.8 td).
It delivers fuel to the main tank via suction rather than a pump. This means that the breather on the original fuel tank has been blocked and the new aux tank now breathes (dragging fuel into the main tank).
Anyway my problem is that the system is now not breathing. this means that after an hour or two I have an 'explosion' under the car of the tank imploding. I simply release the fuel cap to relieve the pressure on drive on.
So, does anyone know what hose I need to unblock? Would have got blocked from all the mud doing the Simpson last year. TJM in
Adelaide were not much help because they have a new mechanic who has not installed one before and calling the manufacturers was not much help either :(
There is one hose only about 10cm long but has a plug on the end of it. Is this the one?? Not keen on pulling hoses off if i don't know what I'm doing incase I make it worse so I can't transfer the fuel at all.
Heading off to
Innamincka in 2 weeks so would love to have the 'system' working rather than having to pull over every hour to take the fuel cap off!!
Ta,
Reply By: Member - ross m (WA) - Wednesday, Jun 10, 2009 at 15:11
Wednesday, Jun 10, 2009 at 15:11
Seems a strange way to transfer fuel from one tank to another.
You would be better off with a 12v pump to transfer fuel from one tank to another.
A tank must have a breather to allow air to replace the volume of fuel that has been used.
Its diesel ,so it wont hurt to remove the plug in the breather and go for a
test drive.
Make sure it wont splash
However once you unlbock the breather,the vacuum transfer will not work and can not in any way that I can see.
Any mechanic should know this in theory
AnswerID:
369322
Follow Up By: Gossy - Wednesday, Jun 10, 2009 at 15:58
Wednesday, Jun 10, 2009 at 15:58
I asked for this type of transfer because I didn't want a pump to die at the wrong time. Less moving parts the better.
This problem is an easy fix once I know what hose to unblock.
FollowupID:
636771
Follow Up By: Member - ross m (WA) - Wednesday, Jun 10, 2009 at 22:09
Wednesday, Jun 10, 2009 at 22:09
I can understand that but a gravity feed might be more practical..
Or a fuel switch solenoid that can supply the engine direct from either tank.
FollowupID:
636837
Reply By: Member -Signman - Wednesday, Jun 10, 2009 at 15:16
Wednesday, Jun 10, 2009 at 15:16
Wouldn't be a breather in the cap that is blocked??
AnswerID:
369324
Reply By: Gossy - Wednesday, Jun 10, 2009 at 15:57
Wednesday, Jun 10, 2009 at 15:57
No the cap is air tight (so I need to be carefull I put the correct cap onto both holes).
Breathing is done via a hose (just not sure which one).
AnswerID:
369335
Reply By: Flywest - Wednesday, Jun 10, 2009 at 16:52
Wednesday, Jun 10, 2009 at 16:52
My Ol Grandmah - always said "suck it and see".
Maybe thats applicable here?
Then again - she also said:-
"Sugar I Hope!"
"Tobacco I think?"
"Ohh Shiate Begorrah -
I can tell bye the stink!". ;o)
So maybe don't listen too much to my long since departed grandmah, specially if you have a sullage tank under that 4 x 4 that could be confused with the long range diesel tank!
Cheers
AnswerID:
369344
Reply By: Member - BUNDY BOY (WA) - Wednesday, Jun 10, 2009 at 20:35
Wednesday, Jun 10, 2009 at 20:35
had the same thing a while ago......quik fix 1/8 drill bit streight through the fuel cap......breathes better untill u sort it out.
bundy
AnswerID:
369400
Follow Up By: Gossy - Thursday, Jun 11, 2009 at 09:18
Thursday, Jun 11, 2009 at 09:18
yep thought of this but nervous about the dust getting into the fuel if I do this. My fuel door isn't exactly dust proof!
A trip up to Mt Dare a few years ago I opened up the door to fill up and could not believe the amount of crap sitting around the caps.
FollowupID:
636883
Reply By: Member - MUZBRY(Vic) - Wednesday, Jun 10, 2009 at 21:11
Wednesday, Jun 10, 2009 at 21:11
Gday
You need to clear the breather on the second tank, not the main tank.
Murray
AnswerID:
369412
Follow Up By: Gossy - Thursday, Jun 11, 2009 at 09:16
Thursday, Jun 11, 2009 at 09:16
yep agree but this is the problem. I'm not sure where/what the breather is.
There is a short hose coming off the top of the tank only about 10cm long with a metal plug on the end of it. Is this it??
Maybe this metal plug has a tiny hole in it (that I can't see) which has dirt in it??
FollowupID:
636882
Follow Up By: Member - Roachie (SA) - Thursday, Jun 11, 2009 at 17:56
Thursday, Jun 11, 2009 at 17:56
I reckon I'd be putting on a longer length of hose; get rid of the bolt and fit a small clear plastic fuel filter....so it can breathe, but not let dust in.....
Roachie
FollowupID:
636951
Follow Up By: Gossy - Friday, Jun 12, 2009 at 09:21
Friday, Jun 12, 2009 at 09:21
yep completely agree. I'll get the hose confirmed by the mechanic tomorrow and then that can be my little project ;)
Leave for
Innamincka on Sat 20th.
FollowupID:
637024
Reply By: GLX3000 - Thursday, Jun 11, 2009 at 13:06
Thursday, Jun 11, 2009 at 13:06
My understanding of any fuel cap is that the cap is responsible for the breathing. Tiny holes, not in line, through several layers of the cap allow the tank to ventilate without spilling fuel. Sometimes a membrane is employed in the cap to act as a one-way valve.
If you are imploding the longrange tank, imagine the stress the fuel pump must be under. Once the suction problem is found, I would seriously consider at least inspecting if not re-building the pump especially as you say you are heading off to
Innamincka.
wood4me
AnswerID:
369503
Follow Up By: Gossy - Thursday, Jun 11, 2009 at 13:12
Thursday, Jun 11, 2009 at 13:12
goog point on the fuel pump :(
Getting it checked this weekend now. The experienced mechanic is back from leave.
FollowupID:
636919
Reply By: Member - MUZBRY(Vic) - Tuesday, Jun 16, 2009 at 12:26
Tuesday, Jun 16, 2009 at 12:26
Gday Gossy
How did you go with the fuel tank?
I found that most people who answered you had no idea what you were talking about .Interesting.
The system that you describe is the same as on Volvo trucks .
Murray
PS..very old ex mechanic
AnswerID:
370298
Follow Up By: Gossy - Tuesday, Jun 16, 2009 at 12:36
Tuesday, Jun 16, 2009 at 12:36
Considering it's a major brand tank and not a homemade bodgy I was expecting an answer really quick. The final solution didn't even match what the manufacturers told me over the phone!!!!!!!!!!!!
Found out via TJM that the breather hose runs along the top of the tank and comes out behind a plastic cover within the wheel arch (that's why I couldn't find it; I was looking in the wrong place). Why would I look in the wheel arch for a fuel breather hose??
A plastic 'cup' sits around the end of the hose to protect it from mud etc. Unfortuantly (but it was alot of fun) the last trip across the Simpson last year we received an enourmous amount of rain hence
the desert was closed but we had to still get out so we had 3 days of a muddy mess.
Mud had got behind this plastic cover which forms the wheel arch and collected in the plastic 'cup' blocking the breather pipe. Banged out this crap and cleaned it and now as good as new.
Most importantly I now know where this hose runs so if it happens again (explosion under the car from the tank imploding) I know what it is and how to fix it :) A phillips head and 1 min of my time.
Like most things. A simple fix once you are shown how.
FollowupID:
637609
Follow Up By: Member - MUZBRY(Vic) - Tuesday, Jun 16, 2009 at 18:35
Tuesday, Jun 16, 2009 at 18:35
Gday
Thanks for letting me know what had happened.
Much appreciated.
Murray
FollowupID:
637690