Fuel Pump fail check after LPG conversion GU 4.5 Petrol 2000

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Hi all

I am having a fuel pump issue so the I am on the hunt for a replacement/fix. I have been ringing around most of the morning and early afternoon trying to get some fuel pump information.

GU 4.5 litre 2000 Y61

We had the LPG conversion done in 2009, however that business is no longer operating - so not helpful

I only have the sub-tank for petrol, the main tank has been removed.

Ok so the issue is that I am not getting fuel, I have checked fuses and relays and I am getting power to the pump assembly for the sub-tank. I can start and run the car on Gas but with some resistance having to turn it over for a while longer, I have been told the LPG system requires a petrol boost to start up?

What I am trying to figure out is if the reserve tank fuel pump is the correct/original pump for that tank or has the main tank pump been installed in the sub-tank. I'm going around in circles trying to work this out as I have read that the pressure of the pumps may differ. My 'Gregorys' manual has pictures of both and they look very similar. The one I have however looks more like the sub-tank one. My question is if the sub-tank pump has enough PSI to run the car on fuel, or as I said if the main tank pump has been put into the sub-tank. As I said the manual photos I have seen give me a 90% positive it is the sub-tank pump.

I've got a price from Nissan for the sub tank being $450+ tax, and the main and one being $706 plus tax ... ouch!

I have numbers on the existing pump, being A42-S04 007 9X15D, however when I gave those numbers to Nissan they said nothing listed for that? Maybe no genuine but it does have the Nissan seal on it (for whatever that is worth)

So I then contacted Repco and they were in the same situation, they advised they would simply call Nissan with the same number and so on.

I then called Covs Parts and gave them the number, after which they said they have a non genuine pump for $133.00 - big difference! I need this fixed ASAP so I have confirmed the order of that pump.

Meanwhile I am hoping someone here can maybe shed come light on this for me.

Thanks

Greg

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UPDATE: I have spoken with several LPG conversion places that have all said the same ting the sub-tank pump is not changed. So I have replaced the fuel pump, the in-tank sub-tank and then noticed that was not working ... I retested the new fuel pump from the battery test I used yesterday and no power. I then tried it via a different battery and both work, must have been a faulty battery. I am however still having not getting fuel.

[dom14]

UPDATE: I have spoken with several LPG conversion places that have all said the same ting the sub-tank pump is not changed. So I have replaced the fuel pump, the in-tank sub-tank and then noticed that was not working ... I retested the new fuel pump from the battery test I used yesterday and no power. I then tried it via a different battery and both work, must have been a faulty battery. I am however still having not getting fuel.

I've noticed during my dramas withe intank fuel pump that if I try to run it without submerging the pump pickup in petrol it sucks in air and subsequent submerging in petrol won't work(it won't pump petrol) even though I can hear the pump running. The way to overcome that was to stop the pump running and start again(disconnect the power to the pump and reconnect it). This was while having the pump on a bench with a small petrol container to produce the conditions inside the tank.
I'm not certain whether this is a pump fault or not, but I suspect it is, 'cos when the tank run out of petrol the pump does get filled with air through the breather(s) so the same condition can produce the same result. Turning the ignition off and turning on again can mimic the scenario of power disconnect/connect. My overall guess was that the pump was faulty so I wired up a cheaper external pump while still having the internal pump & it's plumbing(sealed but left alone in case I wanna swap over the external pump plumbing lines to the internal pump). I opted to not to purchase a new internal pump 'cos I wasn't sure(still not sure) whether the pump is faulty or not(internal pump is around $150 and I didn't wanna spend that much money without confirming it). External pump setup was super cheap and effective, but I will have to get back to the internal pump issue sometime in the future.

I think the internal pump is indeed faulty in my case 'cos when the vehicle in on LPG(I run it on LPG all the time) the intank petrol pump still runs all the time, and there is no petrol in the petrol tank most of the time. I reckon it's been pumping air(pumping dry) for too long and that might have partially stuffed it up. The wiring by the LPG guy was bad to make it run all the time I reckon.
I have corrected that issue by rewiring so the petrol pump doesn't run anymore while the engine's running on LPG.

I'm not sure how all these directly apply to your scenario, but I think there is a lesson in it for you.

[dom14]

Hi all

I am having a fuel pump issue so the I am on the hunt for a replacement/fix. I have been ringing around most of the morning and early afternoon trying to get some fuel pump information.

GU 4.5 litre 2000 Y61

We had the LPG conversion done in 2009, however that business is no longer operating - so not helpful

I only have the sub-tank for petrol, the main tank has been removed.

Ok so the issue is that I am not getting fuel, I have checked fuses and relays and I am getting power to the pump assembly for the sub-tank. I can start and run the car on Gas but with some resistance having to turn it over for a while longer, I have been told the LPG system requires a petrol boost to start up?

What I am trying to figure out is if the reserve tank fuel pump is the correct/original pump for that tank or has the main tank pump been installed in the sub-tank. I'm going around in circles trying to work this out as I have read that the pressure of the pumps may differ. My 'Gregorys' manual has pictures of both and they look very similar. The one I have however looks more like the sub-tank one. My question is if the sub-tank pump has enough PSI to run the car on fuel, or as I said if the main tank pump has been put into the sub-tank. As I said the manual photos I have seen give me a 90% positive it is the sub-tank pump.

I've got a price from Nissan for the sub tank being $450+ tax, and the main and one being $706 plus tax ... ouch!

I have numbers on the existing pump, being A42-S04 007 9X15D, however when I gave those numbers to Nissan they said nothing listed for that? Maybe no genuine but it does have the Nissan seal on it (for whatever that is worth)

So I then contacted Repco and they were in the same situation, they advised they would simply call Nissan with the same number and so on.

I then called Covs Parts and gave them the number, after which they said they have a non genuine pump for $133.00 - big difference! I need this fixed ASAP so I have confirmed the order of that pump.

Meanwhile I am hoping someone here can maybe shed come light on this for me.

Thanks

Greg

AFAIK, during the job of removing the main tank(to make room for the LPG tank) they transfer the petrol pump from main tank to the sub tank(or a separate custom built long range petrol tank, as in my case).

As for the LPG needing petrol boost to start up is not correct IMO, but I'm sure there are folks and LPG techie's that disagree.
IMO, starting on LPG is better as the rich petrol mixture during a cold start can cause additional friction wear and tear inside the combustion chamber, namely the piston rings.

LPG guys and some LPG literature points out different reasons for cold starting on petrol and switching over to LPG after few minutes. Below short article explains scenarios or reasons to cold start on petrol all the time(neither scenarios apply to me 'cos mine is not EFI and the Melbourne winter hardly cold enough to cause LPG evaporator freesing afaik). It may apply to you, so have a read.

http://www.go-lpg.co.uk/Do_I.html


Mind you, I should mention that afaik some LPG systems are designed to start on petrol and then automatically switch over to LPG after the engine's warmed up(five/ten minutes or so). I am not sure whether your system is like that. Your issue can be an issue with the switch over switching electronic unit not doing it's job properly as well. If you can start on LPG without any issues while you can confirm no petrol is getting into the engine during that time, then you know your system is not designed to start on petrol automatically regardless of which fuel the fuel selector is set to. If you CANNOT start on LPG at all, then it's reasonable to suspect the auto switching of petrol to LPG isn't working properly perhaps due to faulty switching unit.

Dual fuel systems can cause many issues 'cos many installers don't do a proper complete tweaking for the engine to work in both fuel types hassle free. If you're having starting issues with LPG cold starting then it can be either

1)It's not properly tuned(Ignition time curve wise) to cold start on LPG or

2)Designed to start on petrol and switch LPG after initial warmup(and it's not getting petrol into the injectors to do that due pump issue or auto switching unit issue) or

3)The installer hasn't installed a cold starting primer solenoid to prime the LPG mixture during and LPG cold start.(it is basically a electric solenoid that activates the vaccum from intake manifold to the priming port on the LPG evaporator. Vacuum hose goes from intake manifold to the evaporator. Solenoid valve/switch is attached to the priming port on the evaporator while the other end of the solenoid attached to the vacuum hose.)

[dom14]

Ok so the issue is that I am not getting fuel, I have checked fuses and relays and I am getting power to the pump assembly for the sub-tank.

What you can do is to give power directly to the subtank pump from the battery and then have the petrol line disconnected near the injectors and see if the petrol's coming out. Do it before the petrol cut off solenoid and after. That way you can confirm whether there is a pump issue or not.
I'm assuming you've already tried disconnecting the fuel line near injectors/petrol cut off solenoid and checked whether petrol is coming out or not when ignition on & cranking(on both LPG & petrol if you have a fuel selector switch on the dash).

[dom14]

These are the relevant threads I created during my tank/fuel pump dramas. They might be useful to you.

http://www.nissanpatrol.com.au/forum...417#post742417

http://www.nissanpatrol.com.au/forum...k-access-issue