LPG problems

[zukmeista]

Got a Nissan Patrol, originally a carby TB42 but converted to dedicated LPG, manual gearbox, drove into town this morning (about 5K), on the way home it slowly died, wouldn't rev, gas gauge says half full, sprayed some starting fluid in the air intake and it fired, so would assume run out of gas, but can't fill it as it is due for inspection, I have read it is possible to hook up a barbeque bottle somehow, how is this done as I want to know before I get someone to fix it and spend lots of money to find it was just out of gas.
Help would be appreciated.

[mudlva]

couple of things to look for

Q. does it start cold easy enough then after a while start running out of gas
A. could be a coolant circulation problem with the heat transfer unit
Q. is it hard to start, runs a little then dies
A. the mixer has a small vacuum hose to the heat transfer unit it may have a little hole or loose hose end

Test. with the tank outlet valve closed, undo the hose that goes into the heat transfer unit, it will discharge a lot of gas as you let it off, caution as its real cold and will give burns. go back to tank and turn valve a little and very slowly gas will start ejecting from hose end.
result> knowledge that there is gas and its getting through to the unit
lpg if used for many small trips will start waxing up and blocking jets etc, normally a good hard run will sort this problem out

re the caravan bottle option

the hose will need to be made up for you
the one that i had was made so it screwed into the inlet fitting into the heat transfer unit ( the same one as when you disconnected the hose to check tank pressure) then it ran through a hole in the fire wall into the passengers foot space. it was then connected to a caravan bottle (make sure its up side down) and away you go. with my 400ci sbc i got about 55ks before it to ran dry but hay i had another bottle so it was all good

[zukmeista]

It won't start at all now, but will fire if starting fluid is sprayed in the air intake, it has done a few short runs lately. The air filter has been burnt away, I presume this is from backfiring?

[dan.c]

if its been backfiring check your carb, my 3y lpg hiace backfired and melted the carb, new carb and a tuneup and all good again

[zukmeista]

When you say check it , do you mean see if it has a hole melted in the side of it? It looks fine to me.

[mudlva]

you will need to check that you are getting gas to the heat unit first and foremost

then check that little hose as the heat unit will need vacuum to it before it will release gas to the mixer

lpg should not backfire as it doesn't build up like petrol as far as i know

all the gear that i have played with have been impco unsure of other brands and how they work

another note i have found is if the battery is not turning the motor fast enough then it will not create the vacuum to open the heat unit. try adding a fresh battery with a set of jump leads

[zukmeista]

Battery is fine, spins over fast as. From the stickers in the engine bay it appears to be a "Lovato Autogas" system. I can't see a vacumnhose going anywhere? Here are some pics of the setup:

[mudlva]

dont know that system but track where that metal pipe goes to it may be the vacuum pipe that impco use
it looks like it head to a solenoid unit maybe its a cut off valve of some form
have you checked for gas from the tank to that unit?

[pressy]

two things come to mind. 1/ check the petrol/lpg switch for power and the switch working. 2/ on the bottom of the the regulator there should be a bung from the pic looks like a bolt take that out and see if any wax comes out,3/ also push the primer button on the side of the solniod valve and see if you can hear a gas noise.4/ you should hear the shut off solniod click when turning the key on and off or the petrol/lpg switch.

other wise you may need a re kit of the reg.....

where are you in our great country?

[dan.c]

mine looked good externally, when i pulled it off it had melted inside, jamming and sealing up the butterfly valve in the carb

[northdude]

as said check for gas first that steel pipe is the high pressure gas pipe from the tank you could probably open the bleeder thats inside the compartment at the tank to see if theres gas

[zukmeista]

Well the solenoid clicks, judging from the way it stopped running (very slowly) I am guessing it has run out of gas, it is going to get re-certified tomorrow so I'll soon find out.

where are you in our great country?

Check my profile, some people actually bother I have pulled that bung out, nothing came out. Not too keen to play with the gas, I'll let someone else fix it instead of blowing it up.

[lokrite]

The black box with 4 wires is a electronic safety switch
when first turning ign on it switchs for a second to open gas valve and prime system
Once engine starts it take a pulse from coil neg /tacho feed or alternater to keep gas valve open ,if engine stalls it stops gas flow reducing fire risk etc
You may have manual prime wired in if you have a rotary switch in cab ,just push in to check for gas valve clicking and yes they do shit themselves my first one lasted 2 tanks of gas so try get a spare if gas only in truck .
You can bypass in the bush if you have to but use a switched power source
Also turn tank valve on slowly as most have anti freeflow feature built in
cheers nick