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sfrrob
2nd February 2019, 07:59 PM
Hey guys, just a quick question.
I have pulled out the LPG system from the RB30 Patrol. And I removed all of the engine bay wiring associated with it, it was a shamozzle......

I just went to fire it up after doing a head gasket replacement and she won't fire up. I can't see any fuel in the carby window and the thicker fuel hose is dry even after cranking for a while after I reconnected the LPG and Petrol switch under the dash.

I am not sure what to do.There are 2 solenoid things bolted to the inlet manifold. One has a fuel hose in and out that goes up to the fuel inlet on the carby. The other just has breather hoses one to a t piece on the inlet manifold behind the carby and the other to the top of the airbox.
I removed them and plumbed the fuel line directly to the carby and still no joy. To me they are pointless as it's just another thing for the fuel to go through instead of directly from the thing with a big barb and smaller (return) barb. ( Which has me buggered as well.... Don't see the point in that or understand how it works exactly)
I climbed under the car and had the Mrs put the ignition on but can't hear any fuel pump noise from the tank. The LPG and fuel switch are still wired to the wiring loom under the dash, 4 black wires from an immobilizer or alarm thing into a red wire which is powering the LPG and petrol switch.
Confusing... I know.


Is there a way I can just return everything back to how it was and should be from the factory so I can get this car running for a road worthy?
My Haynes manual is at my folks joint an hour and a half away, I asked for pics but thought I'd try here while I wait.


Any help would be appreciated. It's doing my head in!


Rob

sfrrob
2nd February 2019, 08:02 PM
Sorry.. when I said breather, I meant vacuum.....

mudnut
2nd February 2019, 08:26 PM
The fuel goes to the fuel filter then a dividing bulb with one path to the fuel return solenoid which allows the fuel pressure to bleed off at revs lower than 1450 rpm (should show volts at low revs). The other line goes to the carby. I would suggest checking that the needle and seat isn't stuck shut or the return solenoid isn't stuck on.

sfrrob
2nd February 2019, 08:33 PM
Thanks mudnut. Was hoping you'd reply.
Can I ditch the 2 solenoid things that are bolted to the manifold which the fuel has to travel through. They DO click when the ignition is on. But to me it seems to be something added when the log conversion was done.
I am pretty new to turning spanners on engines Soni am still learning. What I want to do is just revert everything back to standard
Pre-LPG.
How do I add pics via my phone?

sfrrob
2nd February 2019, 08:40 PM
77830
Attempt one

sfrrob
2nd February 2019, 08:40 PM
Think I worked it out.
So those 2 things are what I am talking about.

mudnut
2nd February 2019, 09:12 PM
It is a bit hard to see what is going on with those solenoids, but the petrol one could be deleted. Just run a line from the small fitting that splits the fuel to the inlet pipe on the carby. You will have to buy a ready made elbow. Because there were no elbows available at the time, I used a heap of hose clamps all along the length to stop the hose from kinking when I formed the bend.

There are also ready-made supports that stop the hose from kinking on a tight bend.

I would also suggest putting a kit through the carby as running on gas can dry out components and cause problems.

In Victoria a registered gas fitter has to disable the system and put in paper work to Vicroads.

0-TJ-0
3rd February 2019, 11:24 AM
Do you have fuel at the filter when you hit the key?

sfrrob
3rd February 2019, 01:21 PM
Hey mate, I will give that a whirl later. Too hot to be out working on the car right now. I checked the fuel line that is after the 2 into 1 return thing on the manifold and it was bone dry. So I am tipping there is no fuel at the filter either.
Will check it out and get back to you later

0-TJ-0
3rd February 2019, 01:46 PM
I haven't worked on a petrol, let alone a carby petrol in years but I assume there's a electric lift pump to get the fuel up to the carby.

If thats correct it sounds like it has something to do with your lpg/pet selection switch. It would cut power to the pump when lpg is selected.. potentially you need to provide a +12v signal to the wire that would be live when petrol is selected.

sfrrob
3rd February 2019, 02:06 PM
Yes that was my assumption as well. I am by no means a mechanic/auto elec but I am sure it is what you say. The thing I want to know is, how do I bypass the old LPG wiring. The way it's wired in doesn't just mean I can delete all the LPG stuff and turn the key. There is what looks to be an immobilizer which is where the power source for the LPG wiring comes from. This is where it gets complicated, there are wires branching off left right and centre from it under the dash....It might be a case of making sure the immobilizer is unarmed via the hand buzzer controller..... next time I can get out to the car that is. It just proceeded to pour down with gale force winds for 15 minutes just then. I am drenched from trying to hold down the gazebo I have covering my car.... 🤣

0-TJ-0
3rd February 2019, 02:18 PM
Ha! Sounds like a nice day for it..

I'd expect the pump to have it's own relay or fuse? If it does and you can find it I would bypass everything and run a new wire to that for +12v when the ignition is on. Either that or just run new relay/fuse/wires straight to the pump and be done with it.

Old wiring is the devils work.

Then once you have fuel back up under the bonnet you can start looking at deleting the other lpg bits and you'll be able to check if they effect the petrol side of things as you go.

mudnut
3rd February 2019, 03:44 PM
The fuel control relay is situated in the D/S kick panel. It is my understanding that it should run the pump for a few seconds until the oil pressure switch closes and allows the pump to run continuously.

sfrrob
3rd February 2019, 03:52 PM
The whole setup is strange to me. Not that I really know much about that stuff.
But, I would have thought you'd have 1 main bigger fuel line straight from the pump/filter into the carby and have one return to dump over supply back to the tank. Why is there a need for those 2 solenoid things and the 2 into 1 cylinder then back out to ANOTHER solenoid before it goes back to the tank?
Will have a good think about how I am going to tackle this tomorrow. I don't want to delete the immobilizer because it runs my central locking and the wiring under the dash associated with it is mind boggling.

sfrrob
4th February 2019, 02:05 PM
Ok lads, just removed ALL of the LPG associated wiring. Ducked down to my local mechanic and he said just Hotwire the fuel pump with the ignition.
He also said piss those 2 solenoid things off and just run straight from the 2 into 1 (fuel in and return) into the carby, which I have done.
I checked the fuse panel in the drivers side kick panel, with ignition on I have power to the fuel pump circuit.

What is the best way to Hotwire the fuel pump to see if it actually works and pumps fuel up to the carby?

mudnut
4th February 2019, 03:12 PM
If it was me, I would temporarily wire an ignition wire to the Green/red wire at the fuel pump control in the d/s side kick panel. Be aware doing that cuts out the low oil pressure safety feature. If there is a crash, and the motor stalls the fuel pump will still keep pumping fuel until the ignition switch is turned off.

Have you downloaded the Haynes manual yet?

sfrrob
4th February 2019, 03:31 PM
Did some poking and prodding with my multimeter. I have power to the pump. I think my pump is dead. Will post a few pics shortly.

sfrrob
4th February 2019, 03:41 PM
I have a physical copy of the manual but it is at my folks joint a couple hours away. They attempted to photograph some pages for me but as expected they couldn't quite focus the camera well enough for me to make any sense of it.
I thought we could download manuals here, I have tried to click the link for the manual I bought but nothing happens.

sfrrob
4th February 2019, 03:48 PM
77845
0 when ignition off 12.4 when ignition on.
I'm tipping that's the main power supply to the pump.

sfrrob
4th February 2019, 03:50 PM
778467784777848

sfrrob
4th February 2019, 03:55 PM
What would the yellow to yellow wire be?
Would love to know what colour wires do what from the factory loom as well.

So I am certain the pump has failed which would make sense. I drove the car 1 hour when bringing it home. Stopped for half an hour to load up the spare engine. Drove about 50 Meters and the car stalled and wouldn't start on petrol again. Had to switch to LPG and get home on that instead.
Didn't try petrol again.

My car is running an aftermarket fuel tank because my LPG tank was in the factory position. Do you reckon they would have just used the factory fuel pump in the aftermarket tank? I stuffed my back today so I can't drop the tank to check!

mudnut
4th February 2019, 07:18 PM
Yellow/black should be the sender to gauge wire. Black is earth. Green/red should be the pump and black should be earth for it.

mudnut
4th February 2019, 07:27 PM
This should give you some idea of what is happening. This drawing is very similar to the RB30, but there are often differences just to confuse us.

sfrrob
4th February 2019, 07:30 PM
Cheers mudnut.
I poured a little bit of fuel down the carby on my old man's advice and cranked the engine. Nothing happened.... I'm at a loss. I have spark, not sure why it didn't at least cough and splutter. Just wanted to see if it would at least do something. Maybe I installed the distributor wrong. I set the engine to TDC and the distributor was pointing at cylinder 1, at least I think it was the right way round. It was the metallic part pointing to cylinder 1. Is it the right way round?

sfrrob
4th February 2019, 07:31 PM
Thanks for that. I will have a squiz at it. The old man is bringing my manual tomorrow, maybe that might have something useful in it.

mudnut
4th February 2019, 07:36 PM
You need piston Number One to be on the compression stroke. To do this get someone to place their thumb over the spark plug hole and feel for pressure as you rotate the motor by hand.

sfrrob
26th May 2019, 08:22 PM
Bit of an update.....
Had a horror past 3 months with my old man falling very ill and me having to be in Melbourne for most of the time. The GQ sat in the driveway at a stand still. Anyway. I had a local auto elec come a d have a squiz the other day, as I was sick of looking at it. I replaced rotor button and distributor cap. Still had no spark. Sparky unplugged and reconnected a few plugs here and there. Poked this and poked that. Still no spark. Then all of a sudden it fired up...... Still unsure of what it was, but it's running.
The fuel pump also had a dicky connection down IN the tank, that was repaired and it's all good. The carby needs a rebuild BUT I am going to get the GQ a RWC and rego then convert it to EFI. I have all the parts sitting here ready to go.
Glad to report my novice mechanical skills were spot on and head gasket, engine timing etc are all good.
So I should have the GQ on the road in a week or so. Will post a more thorough update then.
Cheers