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Billy T
18-07-2009, 02:11 PM
Hi Team

My kids have just bought a car that is LPG only and we have a couple of problems!

Firstly my daughter was using it for driving lessons and appears to have run it out of LPG, which is a bummer because there is no petrol reserve. Hopefully the AA can help with that, and I assume it can be topped up with a few Kgs via a gas cylinder and adapter cable otherwise it will have to be towed or trucked to the nearest service station, fortunately just down the road.

Secondly, there is a switch on the dash (labelled LPG) with the positions On, Off and Emerg. The last one is spring loaded so it goes back to off when you release it.

Does anybody know the purpose of the Emerg. position, and should this switch be turned off when the car is not in use?

Cheers

Billy 8-{)

somebody
18-07-2009, 02:39 PM
Hi Team

My kids have just bought a car that is LPG only and we have a couple of problems!

Firstly my daughter was using it for driving lessons and appears to have run it out of LPG, which is a bummer because there is no petrol reserve. Hopefully the AA can help with that, and I assume it can be topped up with a few Kgs via a gas cylinder and adapter cable otherwise it will have to be towed or trucked to the nearest service station, fortunately just down the road.

Secondly, there is a switch on the dash (labelled LPG) with the positions On, Off and Emerg. The last one is spring loaded so it goes back to off when you release it.

Does anybody know the purpose of the Emerg. position, and should this switch be turned off when the car is not in use?

Cheers

Billy 8-{)

Just a guess, but maybe "Emerg" means emergency - it could be that there's a reserve LPG tank somewhere in the vehicle?

kenj
18-07-2009, 02:44 PM
The fleet of forklifts I used to run had (from memory 20yrs ago) Off, On, Petrol

I used to tell the drivers to run the last 15 minutes on petrol each day as the carberoosters used to get a build up of a powdery substance when they had not been used for sometime. That powder used to gunge up the jets and cause all sorts of problems.

I would say that "Emerg" is the switch back to petrol.

Ken

R2x1
18-07-2009, 02:49 PM
Not on an LPG dedicated vehicle. Perhaps it is a cunning device which filters the cabin air in the car through an energy extractor while, simultaneously delivering cabbage and chilli-bean soup to the occupants.
Weren't the government proposing to tax this? Maybe that is why it is marked Emerg.

Billy T
18-07-2009, 04:09 PM
Just a guess, but maybe "Emerg" means emergency - it could be that there's a reserve LPG tank somewhere in the vehicle?

I don't think they have reserve tanks, but I did think that perhaps it might bypass a pressure control somewhere to let you start it even when the tank pressure is low and drive to the nearest gas station, but I'm trying to find out more about LPG before I call the AA as they may need to truck it.

Additional informed comment would be appreciated. Where's Metla today when I need him? He seems to be up on all things automotive.

Cheers

Billy 8-{)

Cicero
18-07-2009, 11:51 PM
Be interesting to see if it needs priming.

SurferJoe46
19-07-2009, 06:32 AM
The fact that LPG is not as volatile as gasoline, we have about the same settings on Dual-fuel or LPG-Only vehicles here.

IF there is a gasoline tank still in the vehicle and it HAS some gas in it, then the "Emergency" position is just to prime the system when the LPG is too cold to vaporize well enough to support combustion in a cold engine.

The labeling of switch positions is all a bunch of semantics however as one will say "PRIME" where the next says "EMERGENCY" or "COLD START" and they may mean pretty much all the same thing.

"OFF" may be universal however and require no further edification.

I repaired and managed a few LPG trucks and Ford LN-Series delivery vehicles (NZ= vans) for a major food producing company in Anaheim and we had little or no trouble when one would run out of LPG.

HOWEVER!!!! ->> IF you don't take the precaution and make sure that there is water (or coolant, really) in the cooling system all the way up to the top, then you might frost or freeze the regulator and need to wait for it to thaw out before you can get a successful start out of the engine if it has run out completely.

It will flood the regulator with semi liquid LPG (a slurry) and that will rapidly render the regulator inoperative and fire can result.

It is always best to finish the day's run and switch to gasoline if it's still in the vehicle, as the next day when you want to restart, it is a lot easier with some fuel in the carb to get it running instead of cranking it for a while to get gas from the tank into the carb, allowing it to have something with which to start much more easily.

Some LPG regulators have a small button on the side of the large diameter portion of it to allow you to "flood" or prime the engine to help it fire up when cold. If the regulator gets too frosty, you can always run water from a garden hose over it for a while to melt the ice.

Otherwise, there may be a "PRIME" position on the dash valve to perform the same function.

prefect
19-07-2009, 10:21 AM
I think when you turn and hold at emergency position it opens up a solenoid valve which sends a puff of lpg to the throttle valve.
Bit like a primer system on a piston aircraft engine.