LPG tank for 98 XJ

[sparks1121]

Hi all
Thinking about buying a 98 XJ and just wondering where the LPG tank would go if I convert to dual fuel, just in case the petrol bill gets a bit scary :eek:
Thanks

Sparks

[Jeepdownunder]

Mine is under the rear in place of the fuel tank. I have a long range petrol tank under belly. My advise LPG is for cooking. People claim you go 10% less on Gas than petrol, its more like 20% and go's up towing or into wind. Add on $18-00 a litre for cylinder lube at around 20 to 30 tanks off gas per litre and also that gas can go as high as 54 cents a litre gas is not much cheaper than a well tuned petrol. My advise don't bother paying the money. I may even get rid of my gas system. I have one of the best but I have had two explosions the second when gas built up in the manifold and ignited blowing the vacuum hose off the break master cylinder leaving me with hardly any breaks. Gas was good when it was 17 cents a litre but now? Think carfully.
Cheers.

[dxj]

Hi,

I second Jeepdownunder regards financial viability of LPG.

I have factory fitted LPG on my VS holden.

Fuel economy when running petrol is around 10 to 12L/100km, can be as good as 8. typical 10.5

Fuel economy when running LPG, Best 11l/100km worst 16l/100km. Typical 14.5

So I use nearly say 25% more LPG than petrol.

LPG requires plugs change very often. Very sensitive to bad plugs, causes misfire.

LPG requires operator knowledge. ie Must start on petrol otherwise difficult to start. ( holden factory gas automatically start injecting petrol even when on LPG )

LPG requires upper cylinder lubricant for most engines. ie must regularly switch back to petrol or buy upper cyl lubrication kit.

LPG converter restricts air flow to engine slightly. You will use slightly more petrol when switched to petrol than you do now!

LPG motors run hotter. LPG is a hotter dry fuel.

LPG needs more spark advance and higher compression to function properly. ie normal engines don't extract full power from LPG.

Petrol injectors tend to gum up easier on LPG motors as they don't have any self cleaning while LPG in use.

Some figures:-

Buy/fit LPG $2000.00

Loss when selling as LPG vehicle unpopular $1000.00 ( or more )

Extra service costs, converter overhaul, extra plugs, special rego check etc etc. Over life of vehicle say... $1000.00

Total capital required for LPG over vehicle life.
$4000.00

Fuel costs:-

typical petrol say $0.90/litre
typical LPG in Sydney $0.49/litre

LPG parity for extra fuel consumption: $0.49 * 1.25 == $0.61 ( balances the km/litre error)
So corrected for poorer performance LPG per litre cost difference == $0.29/l

Now $4000.00 capital at 0.29/litre means I must travel a long way to recoup costs :-

Effectively difference in fuel costs is 13,793 litres (4000/0.29) to get capital payback.

Running on petrol I must do 13,793 * (100/10.5) km to get even on cost == 131,363km

So after you travel 131K on LPG you are breaking even. Then you effectively save 0.29cents per 10km

LPG motors usually need valves and head job much earlier. ( mine had it done at 170K ) say $1K maybe more for Jeep. I had the heads "fixed" for LPG with chrome-moly valves and seats etc etc cost me $2K

So at current LPG prices I am still losing money after 210K.

Altogether different if prices were even close to what they were in 1996 when I bought my car.
Then LPG was typical 24.9 cpl best 19.9 worst 34.9 Petrol was between 0.69 and 0.79. ie LPG was 1/3 price of petrol. Now LPG is 1/2 to 2/3 price of petrol!

Price advantage was nearly double then. Now oil companies are greedy and GST means LPG is now taxed.

Oh, next time you are out of Capital cities, check the LPG price... even higher still. Some places only 10% less than petrol.

My advice is stick with Petrol, get a long range tank and fill it when petrol is on discount. You will be in front.

I am also thinking of removing the LPG system. It now has surging problem and requires major overhaul of converter system. I think cheaper to remove it.

Maybe XJ fuel consumption is higher and changes the above figures to be more favourable but LPG has been a big disappointment for me.

[sparks1121]

Wow,thanks for that DXJ and Downunder I think ill give the LPG idea a big miss, maybe I should be looking at a turbo diesel [img]smile.gif[/img]

Sparks

[Jeepdownunder]

Wow at last some one that has done the sums and agrees with me. People think LPG better, you'll hear them say, "Filled the tank on gas only cost 20 bux :D bloody petrol :mad: would have cost $50. *BUT* they have not done the sums: Its Cheaper When You Walk In To Pay The Attendant Thats All, or it seems cheaper.
Try this on petrol, lighter foot, little time for engine to warm on cold mornings, buy petrol early in week when cheaper, walk to the shop rather than drive, round town carry an almost emty tank say quarter full: you'll be suprised how economy go's up with an emty tank only fill for long trips. It sounds tight arse but I do it, its my way of competing with the mungral oil companies.
Keep the car well tuned especially good air flow.
Try walking to the shop for milk three times a week you'll notice the difference in the tank. Because we are lazy we jump in the car & slip up the street and grab some milk.

[ 15 November 2002, 05:18 PM: Message edited by: Jeepdownunder ]

[Gojeep]

Not to mention the pathetic range you get from the 50 - 55 litre replacement tank! I have a licence to fit gas conversions and have not done it to mine own car for the reasons of reliabilty and poor clearance under both the gas and under floor petrol tank.Forget getting gas outside Alice Springs as once you leave the tar ( where the fun begins ) you cannot get gas and you lose ramp over angle as well which I have seen getting hung up all the way across the Simpson on top of the dunes.

[dxj]

Hi sparks1121,

Hate to pour cold water on the diesel idea also but consider my opinions on this:-

Diesel engine is more expensive to buy, usually same price but vehicle includes fewer features to compensate.

Diesel is rarely discounted these days. Truckies get the $0.25 /litre tax rebate so oil companies have ceased discounts. Often diesel in Sydney stays at $0.949/L while petrol on discount at $0.84

If diesel needs work, always more expensive, especially parts.

In short there is good economic reason for dominance of petrol engine.

Buy a turbo diesel for its low revs torque, engine braking etc etc.
Buy a petrol for good acceleration, power, smoothness etc etc.

In general 4wd and fuel economy don't mix. Consider fuel price over life of vehicle vs purchase price rego etc, fuel is not the big cost it is made out to be.