very weird gas problem

[disco97]

Hi Guys
i have a 3.9 auto which was put on gas july last year in the last month or so its been doing some weird things.

few tech things
leads under a year old 8mm champions (i think)
plugs changes also at same time ngk 5bpes?? (the ones everyone recommends)
89ltr lpg tank

now the problem
first i had done 250kms then it had no puff so i went to a servo and it opnly took 47ltrs of lpg thought thats strange but milage was about right for the litres put in.

next time 220km and same thing 42ltrs of lpg
so i cleaned the dizzy cap and button (which are all lucas)

then came a 90km one 19ltrs to fill
and no puff to even drive

next one 200ish km and same thing and 50litres to fill it

now when this problem happens i cant touch the accelorator or it just feels like its bogging down but soon as i fill the tank its fine.

i cant see why i have this happening as theres plenty of gas left in the tank but no go.

i took it in for a tune and oil change and go to pick it up and NOT TUNED but charged for oil and filter change of $220 . when we spoker to him he just says no time blah blah and when pressed on the issue he doesnt know whats causing it.

alos how much do you guys get out of your tanks for there size eg:60ltr tank you can empty it and it takes how much to fill??


thanks
jeff

[350RRC]

Hi Jeff,

You don't mention what sort of system it is. That would help. How much gas could you put in it when you got the installation?

Don't know how you'd fit a 89l tank in the rear of a Disco. I've had 2 different 80l tanks in the back of my RRC, one laterally behind the back seat and the current one which only just fits longitudinally. Have seen a 100l tank in the rear of a RRC but there wasn't much room for anything else.

Your first couple of mileage figures are OK.

It sounds like you have a convertor and there is a problem with gas delivery, rather than an ignition prob. If you have a convertor is it iced up when you run 'out of puff' with plenty of gas left?

If so you are short of coolant and / or have an airlock in your cooling system.

cheers, DL

[fraser130]

If so you are short of coolant and / or have an airlock in your cooling system.

cheers, DL

I've seen installers plumb in the converter so that there is no water flow through it unless the heater is on!

next time it happens, try turning the heating on full, and if the heating doesn't heat as it should, or it fixes the problem, then the heating water for the converter needs plumbed a different way.

Let me know how you get on and I'll go into more detail if need be....

Fraser

[tracker]

Hi Jeff,

You don't mention what sort of system it is. That would help. How much gas could you put in it when you got the installation?

Don't know how you'd fit a 89l tank in the rear of a Disco. I've had 2 different 80l tanks in the back of my RRC, one laterally behind the back seat and the current one which only just fits longitudinally. Have seen a 100l tank in the rear of a RRC but there wasn't much room for anything else.

Your first couple of mileage figures are OK.

It sounds like you have a convertor and there is a problem with gas delivery, rather than an ignition prob. If you have a convertor is it iced up when you run 'out of puff' with plenty of gas left?

If so you are short of coolant and / or have an airlock in your cooling system.

cheers, DL

HI, I had a look at this system today.It seems to lose pressure at a half full tank.Converter is plumbed correctly and quite hot when running.To me there seems to be a blockage somewhere between the gas tank and the converter.But not sure where.Is a inline filter fitted to lpg systems?? Brian
ps it is a big tank that justs fits with the puppy seats removed

[Hotdog]

If its a vapor injected system I have heard of blocked filters being an issue with newer installations. After all the gunk from the new tank etc is filtered the blockages become less of an issue and the filters last longer. I have an earlier system with an 80l (water capacity) tank and get approx 300 klms before putting 60 odd liters of gas into it. Yeah i get around 20l/100k's from my D1 3.5 V8,

Cheers

Hotdog

[fraser130]

It's most likely a converter problem, or a loose connection at the tank for the electric safety valve. Converters are a really simple device, so not a lot can go wrong.
I would suggest taking the car back to the installer and asking them to rectify the fault.

[400HPONGAS]

So 250 on 47 = 5K/l
220 on 42 = 5K/l
90 on 19 = 5k/l
200 on40 =5k/l
Well close enough anyway
60 litre tank , probably only squeezes in 50 litres on a cold morning at best .
You been running out of GAS !!! Try filling it up when it gets to half tank .The vapor pressure problem . you may have a Pickup filter problem or a dicky "excess flow valve" in your tank , check the manual shut off valve is fully open . Is it a vapour injection system or a fumigated system ?

[disco97]

ok a few things yes its a vapour system.

where exactly is the filter and is it easy to check?

at most i have put in the tank when it read empty but still had some gas in it i could get 72ltrs in it just after install now lucky to be able to put 50ltrs in the system so it aint running out of gas.

i checked the manual valve first and again yesterday wide open

i suppect its a filter problem too but when we mentioned this to the installer i have never seen a blanker look and he said "nah if its a filter it wouldnt run at all "

it will be going to him again but i go away on sunday night and just wanted to see if i could quickly fix it before i went no big problem petrol still runs fine.

400hpongas i have never run out of gas in the times this has happened it is still half full tank at least

tank is 1100mm long and bloody round i wanted more kms before i had to fill up seeing on most trips gas stations are around 400km apart up north


also i thought it maybe the gas from the servo i use so have filled up at 3 different ones


thanks very much for the help guys

[400HPONGAS]

The symptoms you describe point to the fact , that you are "running out of gas"
I would run it down as low as you can on gas , until it starts to cut out then check the pressures all the way back to the tank .Check the voltages at the solenoid when the fault is occuring .What brand tank , the make model number , and its pickup orientation angle . The service valve has many functions , the Excess flow valve , the pickup tube with a bag filter on the end,the solenoid valve,the manual control valve , any of which could be causing your issue . Obviously check pressure flow either side of the Lockoff solenoid and the filter inside the lock-off solenoid .
If you cant do these things , then take it back to whomever installed it and tell them to FIX it .

[p38arover]

Are you certain it's an 89 litre tank?

If so, is that water capacity (WC)? To find the LPG capacity, multiply the WC by 0.8 -- an 89 litre WC tank would have an LPG capacity of 71 litres -- which is what you got in when installed.

Has anyone removed/refiited the tank and not done so correctly. If the tank has been rotated in the cradle, the float valve might be shutting off early.