Fuel supply failure

[JoshJ]

Hi Guys,

I bought my 3.0GL Patrol late last year Brand new. Since the first tank of diesel I have been having a problem. As soon as the main tank reaches +-1/4 the car just dies due to lack of diesel to the engine. I then dump the Sub tank into the main tank, pump the prime valve until hard and start the car, drive of like nothing was wrong. The first time this happened Nissan came to recover the car and brought 7 liters of diesel. We added it and I drove straight to the nearest pump and filled up. I could only get 62 liters into the tank. Thus it was not empty when it died.

The car has been at the dealers a few times. They replaced the level unit. They have checked the system for air leaks. Check the breathers on the tanks with no success thus far. It has been concluded that the car still has +-30 liters of diesel left in the tank at around 1/4. They are now going to log a call with Nissan SA to see what they say.

does anybody have any Idea's on what the problem could be?

[bogeyman]

Josh,
The pick up pipe inside the tank is most probably the culprit.

Don't know if they are the same , but on one of my 4.2 pickups I had to clean some dirt from that pickup pipe. It has a big assembly of plastic and filtering nonsense.
If any of these plastic clips came undone it would shorten the pipe and will fail to utilize all the fuel in the tank.

That pipe could also be bent or cracked halfway up.

One last thought , The breather can be blocked causing vacuum in the tank with the same result.

Chris

[bogeyman]

Sorry , I see you have the breathers covered.

[dieselfan]

Definitely the pick up. I hope Nissan replaced the level unit at their cost. Replacing the level unit based on your symptoms makes no sense.

[JoshJ]

Hi Guys,

Thanx for the replies.

They did replace the unit on their costs. Actually they have been very kind and helpful. I have not had to pay anything yet.

Dieselfan - I agree that there reasoning makes no sense and did tell them so. If the system leaked at any point from the tank to the pump, the car would die at anytime not only on 1/4.

Bogeyman - I suggested that they should check the pickup because it made most sense to me that it has a crack or fault on the 1/4 depth of the tank. That it sucks false air at the pickup on this point. They said that it was replaced with the unit and they rechecked it the second time and all seems well. I still have my suspicions though.

Also, even if the level is faulty the car should still run because it has fuel available in the tank. Another thought is that the pump may be faulty. with the gravity feed from the tank the car runs but as soon as the tank gets low in level and there is less gravity pressure and the pumps needs to know suck it then can't keep up. This is a stretch I know, but if all is sure and true, what else can it be?

They logged the call to Nissan SA. So hopefully this weak I will get some feedback.

will keep you posted.

At least OS starts every time and remains an awesome
Fitted 33inch Muds 2 weeks ago and is definitely looking better to.

[bogeyman]

Josh,
This might be a long shot , but stranger things have happened:
The pick up pipe might be from another model or a factory fault caused it to be shorter than the full immersion depth in the tank.
They must measure the depth available in the tank and the pipe length.

Just a thought.

[JoshJ]

Hi Guys,

Os is at the Dealers again. still trying to solve the tank gauge problem. apparently Nissan SA got back to them after a few weeks. and they now have new ideas and things to check. So I am now demoted back to a "plat kar" for a couple of days. A new Nissan Sentra, courtesy of Nissan. not a bad ride. But no where near the Beast.

I'll keep you posted.

[JoshJ]

Hi Guys,

some feedback on the fuel supply failure. The car was with Nissan from Monday to Wednesday. They got a whole lot of things from Nissan SA that they had to do. like calibrations. checking the clusters and so on. They also drained the tank to confirm the amount of diesel in the car at quarter. I gave it with a tank level just above quarter. they drained 25 liters diesel out of the main tank. so it was safe to say that even though it died at quarter it was never actually empty. well they said they believe it should be fixed and I can come and collect it. Took it for a drive and dump some fuel from the sub tank to the main tank just until it was above quarter where it usually died on me. went to the garage and refilled the sub for standby. (this has become the routine for me. drive the main tank low during fault finding. keep the sub full for emergency.) I drove home and parked the car for the night. no problems. left for work the next morning and whamm it dies again. dumped sum diesel from the sub and primed the fuel line. started the car and drove to work. when got to work the tank was almost half. I phoned the workshop manager and told him it is still doing the same. he said he will phone me back he needs to speak to Nissan SA again. after work I drove home and whamm the car dies again, this time to my amazement because it has never died at the half mark. went through the usual routine. started the car and drove off. however this time the car did not have any power at all. so I crawled home. phoned the works shop manager again. he said I must have the car there Friday morning bright and early.

I got there and they hooked it up to the computer. this time however the mechanic who has helped me the very first time was there again. ( i did not see him around there for some time. apparently he was on training). Good oak, I like him from the first time I saw him. he hooked it to the computer and it threw out errors like diesel pump failure, fuel leak and fuel pressure. so he pulls out his phone and is soon after having a huge discussion with someone on the other side of south Africa. Apparently the guys in cape town see a lot more Patrols then around here. and he spoke to someone he met on the training session they had. this guy suggested that they remove the diesel water filter (i don't know how the system use to work. but mine has a filter in the diesel system for removing water and another filter for removing dirt). Apparently this causes fuel issues. but on patrols with more kilometers on the clock. mine only has 5000km. but he said that they should try it. Bypass the water filter and reset the computer again.The workshop manager then put himself, the workshop foreman and the mechanic on standby for me for the weekend. the mechanic had to go home with the computer and tools. if the car dies again, i was not allowed to start it. they must be phoned and then they will come and plug in the computer so that they could see what happened. so they did that and I took off. with a half full tank. so i decided that i am not going to wait for quarter to come so i drove over a 160 kilometers up and down until the low fuel light eventually came one. ( I told my wife while i was driving up and done purposefully trying to empty the tank. i thought to myself that i'm probably the only idiot in SA trying to drive out fuel. at the current prices everybody is trying to save fuel. ) since then i have managed to drive the car empty twice without incident.

so it seems as if this solved the problem. how the filter knew when the car was quarter I don't know .
the mechanic also reset everything with an older version computer on top of using the latest one. he said that since the car is using old tech it might help. maybe this was the solution.

I DON'T CARE THE CAR IS FIXED AND I AM SO RE-LEAVED.
I don't want the water filter back. it seems if these filters are highly sensitive for dirty fuel. this might explain why I had problems from the beginning. I drove from the depot in Durban where they keep the new cars coming of the ships. they filled it there in the depot. maybe the diesel was dirty. cause since i have the car I have never been able to drive it past quarter without it dying on me.

apparently their is a mod that the cape town ouens do. they put in a filter that does both in one. removes water and dirt in one filter. so we will see if this is the route we are going to go. I will keep you posted.

[Herrie]

Ek is bly alles is nou reg!!

[bogeyman]

There are filter systems available that you can fit in the fuel line in front of the Nissan filters to pre filter out water and dirt.
I use Fleetguard filters on all my diesel generators. You will see them on all new big trucks.

Water in the diesel injection system is to be avoided at all cost.