sub fuel tank and how it works
Submitted: Tuesday, Dec 29, 2009 at 20:27
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03busa
HI,i have a 92 landcruiser,and when you push the sub
tank switch on, the light comes on but goes out again.If you turn the key off and on and then push the switch you can here the pump go on and then off again.you can do this as many times you like and it will work for about 30 seconds,start the cruiser and you cant even get a sound out of it.Can anyone help?
Cheers Russell
Reply By: Member - Rob S (NSW) - Tuesday, Dec 29, 2009 at 20:46
Tuesday, Dec 29, 2009 at 20:46
Hi Russell
Are we talking petrol 80 series?
If the sub
tank is low/empty on fuel it will do as you say,run for 30 seconds and stop.
It automaticly stops pumping fuel when empty.
If it is shutting of when full or half full/empty probably some fault in the fuel
tank sender unit.
Also every time the ignition is turned on the sub
tank pumps for 30 seconds.
to keep the system from clogging up. and you will notice the sub
tank level drop over time. you do need to keep fuel in it.
Rob.
AnswerID:
396843
Follow Up By: 03busa - Tuesday, Dec 29, 2009 at 21:03
Tuesday, Dec 29, 2009 at 21:03
Yes sorry it is a 80 sereis petrol and on gas.Sub tank is half full and it wont turn on for 30 sec unless you push the switch when key is tuned on.
Thanks Russell
FollowupID:
665568
Follow Up By: Member - Rob S (NSW) - Tuesday, Dec 29, 2009 at 21:11
Tuesday, Dec 29, 2009 at 21:11
Were's your gas /lpg tank fitted?
they removed my sub tank to fit the gas tank.
FollowupID:
665575
Follow Up By: 03busa - Tuesday, Dec 29, 2009 at 21:22
Tuesday, Dec 29, 2009 at 21:22
The gas tank is fitted in the back against rear door.It can be a bit annoying having to get over it sometimes when you put something in the back.Extra seats still fit in too.
FollowupID:
665583
Follow Up By: Member - Rob S (NSW) - Tuesday, Dec 29, 2009 at 21:33
Tuesday, Dec 29, 2009 at 21:33
Looks like a trip to the auto elece.
other than checking the wiring and plugs at the transfer pump located under the back in front of the sub tank.
But at a guess it would be the float switch in the tank.
FollowupID:
665584
Follow Up By: 03busa - Tuesday, Dec 29, 2009 at 21:37
Tuesday, Dec 29, 2009 at 21:37
Rob, i have been under there and checked all that and all seems to be good,relay to the fuel pump maybe next.
FollowupID:
665585
Follow Up By: Member - Rob S (NSW) - Tuesday, Dec 29, 2009 at 21:46
Tuesday, Dec 29, 2009 at 21:46
The relay sounds to be working as you say you can hear it pump for 30 seconds.
Something is telling it to stop?
ie the float level switch?
FollowupID:
665587
Follow Up By: 03busa - Tuesday, Dec 29, 2009 at 21:54
Tuesday, Dec 29, 2009 at 21:54
Yes maybe it could be. Thanks for your help, i will have another look tomorrow
FollowupID:
665594
Follow Up By: Member - Mudduck (NSW) - Wednesday, Dec 30, 2009 at 09:18
Wednesday, Dec 30, 2009 at 09:18
I think Rob is onto something with the switch rather than the relay. You might also ask this question on offroad80s.com as they are all 80 nuts.
FollowupID:
665633
Reply By: Member - Graham H (NSW) - Tuesday, Dec 29, 2009 at 21:13
Tuesday, Dec 29, 2009 at 21:13
03busa
when 80series are converted to LPG .Sub tank is removed & LPG tank fitted in it's place @ LPG tank gauge is wired to the Sub tank gauge.
So Sub tank switch does nothing as has no petrol connected to it.
From Graham
AnswerID:
396852
Reply By: Member - Keith C (NSW) - Tuesday, Dec 29, 2009 at 21:14
Tuesday, Dec 29, 2009 at 21:14
G/day.the sub tank is replaced by the lpg tank in most 80s conversions and the sub tank gauge becomes the gas gauge, unless of course the gas tank is in the back behind the seats,the spare goes on a carrier on the rear bar if the tank is underneath.
AnswerID:
396853
Reply By: 03busa - Tuesday, Dec 29, 2009 at 21:33
Tuesday, Dec 29, 2009 at 21:33
No everything is still wired up normal just gas fitted behind
seat. I have been trying to get this working for a while now.There is a fuel pump controll relay in the back left quater panell or where the jack is and above the wheel arch.This is what i am starting to think it is.
AnswerID:
396860
Reply By: Member - Howard (ACT) - Wednesday, Dec 30, 2009 at 09:51
Wednesday, Dec 30, 2009 at 09:51
03 busa,
is your vehicle an early or late 92 model.
when the same thing happened on my late 92 model it was the overfill level float in main tank sticking and there is a cut out switch preventing pumping from subtank when tank isover about 2/3 full. (this is a separate float to main tank fuel guage)
I also had the fuel system warning light on the dash permanently glowing.
rather than remove main tank and fix float i just ran a live wire(via a switch on the dash) to both solinoids which are located in front of the sub tank.
one solinoid is normally activated by the float switch and the other by the sub tank switch . the second wont work without the first.
removed the bulb from the warning light to get rid of that.
got into the habit of only pumping up after low fuel light came on then there was no likelyhood of overfilling main tank .
hope this helps
regards
howard
AnswerID:
396916
Follow Up By: Member - Howard (ACT) - Wednesday, Dec 30, 2009 at 09:57
Wednesday, Dec 30, 2009 at 09:57
sorry should read sut out prevents pumping from subtank when MAIN tank over about 2/3 full.
BTW-are you trying to pump up to a main tank that is already over 1/2 full .
my current 80 (97 model) wont let me pump until main is just under 1/2 tank then cuts out with main between 2/3 and 3/4 full.
FollowupID:
665639
Reply By: 03busa - Wednesday, Dec 30, 2009 at 19:46
Wednesday, Dec 30, 2009 at 19:46
Hi,didnt get a chance to have a look today.I replaced fan belts radiator hoses,grease,oil and filter change ready to go away for new year.
Every one have a great new year and i will catch up when i get back.
Cheers Russell
AnswerID:
396988