LPG Conversion of Series 3

Hi there,

now that I've done it, I thought to share my experience with the LPG conversion.

My 1978 S3 LWB got a Lovato Venturi system and a 65l Tank. The tank is monted on the offside, right behind the drivers seat (I wanted to keep the full length of the load area in case we have to sleep there). The conversion costs 1200-1400EUR (1100-1300 Pounds), less if you do stuff yourself. Tank and stuff included, I think the "Tuev" included too (MOT is called Tuev in germany).

Now having done 200 miles the system got driveable, as the diaphragm loosened. At the beginning I had to keep the revs up at around 1600-1800rpm, but now she's "ticking over" at 1100-1200rpm. I still want it back to 600-800, but it needs time.

Pictures and consumption data will follow, as the conversion is still not quite finished. But driving on LPG, I've found the performance went up, and with the shot dizzy and slightly sticky tappet the 100 miles at 10mpg didn't cost a fortune. Before the conversion she did 15-24mpg (wide range I know, but as daily driver she does motorway, 20-24mpg, and weekends kinda greenlaning). Today I had the feeling she didn't need that much. I'll see on Monday if she's down to 20-24mpg again (no offroading this weekend).

Post any questions here. I'll be at the garage on Saturday, so anything I don't know I'll ask them then. First pictures will be up Saturday I hope.

Cheers

What made you decide to spend 1200 - 1400 euros on a LPG when a 200tdi Diesel would have cost less than 500 euros?

I don't mean this in the insulting manor, i am just interested in what made you go down the LPG route not an engine swap route.

I really can't make my mind up, do an LPG conversion for £500, put the 200tdi in for about £300 ish or just keep it as is and when it dies it dies. It's only there for fun, mainly greenlaning and showing off in so if its worth spending loads on something which may not survive many more MOT's who knows.

Hi Mike,
the decision was based on one major factor: You don't get 200TDis over here in germany.
Furthermore I didn't want to put strain on the GB, OD and diffs as I don't know in what condition they are in. I have Betty only since march, I haven't put the GB apart yet. So it would have been 300 quid for the engine, 200 for parts, about 500 for petrol to blighty and back, plus the time I can't use her because I haven't finished the conversion.
And, I do lots of miles, more than 200 miles per week. LPG is cheaper, and I like how the petrol engine pulls (I do 55 on the motorway...).
If you do the LPG conversion, you still have your car in one piece and a failback system (petrol). You have your tank(petrol) plus one more(gas), minus the space(enough of it anyway). So going to Bulgaria in late Summer I'll be bringing petrol for my wifes car back with me.
If I'd be in blighty I'd propably do the 200Di conversion, but over here the cost of getting an engine is too high. And I use her as daily driver; well over 5000 miles a year vote for LPG.
Just to have a more recent picture, how much is LPG in blighty? Over here it's like 0.60EUR/0.50P, Diesel 1.20EUR/1P per litre

Just calculated that with an LPG conversion I save 1.5EUR per 100km over the 200Di conversion (break even at 9000km with LPG, 5000km with 200Di). And she's hopefully getting a galvanized chassis next year...

I've been running the conversion for 3000 miles now, here are my notes:

Data:
Measured distance: 3706mi
Fuel consumed: 867.5l LPG / 123l petrol
Money spent on fuel: 570EUR for LPG / 156EUR for petrol

Consumption:
Median over sum: 23.4 [l/100km] / 12 MPG (UK)
Median over filling up: 22.7 [l/100km] / 12 MPG (UK)
Max consumption: 27.2 [l/100km] / 10 MPG (UK)
Min consumption: 18.6 [l/100km] / 15 MPG (UK)

Measuring technique:
LPG: Filling up full, then pushing button again for 10secs
Petrol: "Brim to brim"
Distance: Odometer (calibrated as ex-scotland yard, verified with gps and derivation less than 0.5mph for speed and non-measurable for distance)
Timing: TDC verified, measured statically with multimeter and bulb
Further monitoring: vacuum pressure, EGT, RPM, own ears

Object:
Series 3 1978 Land Rover 109 ex-Scotland Yard
2.25l petrol engine, Turner 8:1 head from 1998 (12 years old)
Last rebuild unknown
Last major repair assumed 1998
Ignition coil Lucas (unknown), Sparking plugs NGK (BP5E), Distributor Ducellier (Standard), Carburettor Zenith (Standard).
Fairey Overdrive unit

Notes:
Air filter:
Do not adjust anything without air filter. I had the LPG system adjusted without the oil bath filter and as soon as I put it back: balls. The intake vacuum is so far off that you need to readjust the vapourizer ass soon as you connect the filter again...

Timing:
Dont change the timing! Timing was about 8-6 BTDC, I've put it somewhere near 20 BTDC (accidentaly, as I did it by ear). The problem is you dont notice any pinking, and the plugs looked fine.
Now I've set it on petrol, and running on gas is even better than on petrol on the motorway.

Idle:
LPG needed a high idle for me (about 1200rpm cold, 1700rpm warm on gas, resulting in about 800rpm cold, 2100rpm warm on petrol)

Gas Tank:
Tip: There are tanks that take the space of one "two man bench" on the side like my one. (You can sleep in the back of a 109 just so with load area of 1.80m.)

Verdict:
Advantages:
You spend less money on fuel
Clean oil (really, really clean. With 8l each oil change this really is a major point for me, as you can change less often.)
Engine runs cooler
Engine runs smoother
Engine can be adjusted for torque or speed (and has to be)
Second fuel system, making the car more reliable and robust

Disadvantages:
Initial cost (including overhaul of the ignition system and the intake if it draws ANY air)
Engine must be adjusted for torque or speed (and has to be. Max rpm with good torque low down is not higher than 2800rpm for me, better dynamic setting needs higher idle like described, but making it much more useful)
New system is less robust (vacuum drops in intake manifold, sparking plugs, coil and timing are critical)
Mistakes are painful (I blew my piston rings because of VERY wrong ignition timing, about 20deg BTDC for less than 100mi, 12deg BTDC for long)
Gas tank needs space
Gas capacity depends on temperature (major one in a series with its excellent insulation)


All in all I'm happy with it, but angry at myself for blowing the piston rings. Would I do it again? Yes, but again, only if there's no cheap way of getting a 200tdi. For a petrol engine though I have found LPG is a very good way to prolong the life of an engine and cutting costs, plus having a backup fuel system.


Thanks going to:
Autogas Schmidt, Schmitten, Germany, who sold me the system and helped with the fitting and adjustment. Also helping over the phone when she didn't run well and pulling me up the hill from the petrol station when my replacement coil broke down...

Teflon, and his homepage, for lots of good information.

Contact:
Phil
PM on landyzone or varleyltd AT gmail DOT com

Cheers for the statistics / information, makes very valuable reading / resource.

Don't think i am going to go down this route personally, but still useful

From looking at your stats you're getting an average of 12mpg, correct?

This is equivalent to 24mpg on lpg versus petrol/diesel as the lpg is half the price of petrol/diesel.

But this would assume constant running on lpg...i am actually taken aback at the low mpg of the 2.25 petrol engine, i knew it was bad but thats frankly awful.

As you do a lot of mileage I still can't fully understand why you didn't do the 200tdi conversion. It would have cost the same...11-1200 euros including freight of the engine from the uk.

Not only would the mpg be similar, if not better, but you also would have had a far better top speed and more torque..i see you're in frankfurt, i'd go for a diesel every time knowing the winters down there. I drive 150km a day and sit fine on the motorway at 65for half the journey...for best fuel consumption (30mpg+)..It drops to 25mpg the remaing 75km...A/B roads ...and the engine noise is very acceptable..its the first land rover i've ever had where i'm tempted to have a radio/cd player..

storm99 said:

From looking at your stats you're getting an average of 12mpg, correct?
Yes

This is equivalent to 24mpg on lpg versus petrol/diesel as the lpg is half the price of petrol/diesel.
Plus the petrol to start the engine, as it wont start on LPG now because of the rings...

But this would assume constant running on lpg...i am actually taken aback at the low mpg of the 2.25 petrol engine, i knew it was bad but thats frankly awful.
Yes, it is. But this is with really bad piston rings (oil evaporates out of the crank case breather at a rate of about 1l per 100mi)

As you do a lot of mileage I still can't fully understand why you didn't do the 200tdi conversion. It would have cost the same...11-1200 euros including freight of the engine from the uk.
I did the conversion myself, and bought the system for 800EUR

Not only would the mpg be similar, if not better, but you also would have had a far better top speed and more torque..i see you're in frankfurt, i'd go for a diesel every time knowing the winters down there. I drive 150km a day and sit fine on the motorway at 65for half the journey...for best fuel consumption (30mpg+)..It drops to 25mpg the remaing 75km...A/B roads ...and the engine noise is very acceptable..its the first land rover i've ever had where i'm tempted to have a radio/cd player..
I have a cd radio, and tried doing 50, 55, 60mph on the motorway. No difference to fuel consumption, but it gets a bit loud above 65mph.
But I am sometimes in areas where -10deg C is normal, though I then have my portable gas welder with me

Click to expand...

That's why I got me a 200tdi now, especially with the engine needing a rebuild now anyway...

MikeDowson said:

What made you decide to spend 1200 - 1400 euros on a LPG when a 200tdi Diesel would have cost less than 500 euros?

I don't mean this in the insulting manor, i am just interested in what made you go down the LPG route not an engine swap route.

I really can't make my mind up, do an LPG conversion for £500, put the 200tdi in for about £300 ish or just keep it as is and when it dies it dies. It's only there for fun, mainly greenlaning and showing off in so if its worth spending loads on something which may not survive many more MOT's who knows.

Click to expand...

If you only use yours for fun then say you use £50 of fuel a month. If you would use £30 of lpg, if the system costs £500, it will be over 2 years before you get any benefit from it. I say leave it as it is and then when it dies whack a 200 in it.

khaos said:

If you only use yours for fun then say you use £50 of fuel a month. If you would use £30 of lpg, if the system costs £500, it will be over 2 years before you get any benefit from it. I say leave it as it is and then when it dies whack a 200 in it.

Click to expand...

50 quid a month? That's about 40litres, which is somewhere between 240mi (at 10l/60mi) and 120mi (at 20l/60mi).
Is it worth paying tax for this mileage?
And not to mention this has to go through mot each time, too. One more thing for them to dislike...

But khaos is right, for low mileage LPGing is not worth it. But so is a conversion, too.

30 litres of petrol for £50!! Surely some mistake??

thanks storm, now corrected. over here in Krautland this is now correct... though it was some time ago that about 50EUR would buy you 30litres, now it's better again