Running an S Class on LPG

[BeeJay]

I bought a S280 a month ago. My drive to work is a 130 mile round trip from a village in mid-Wales to the centre of Wolverhampton. As a result it is a good mix of country lanes, A roads, dual carriageway, motorway and city driving. I am getting 30mpg, which does not seem to vary much even on the weeks I was driving with 'enthusiasm'.

As I clock up about 30 000 miles a year I have put it in this week for a LPG conversion. I am having two tanks fitted. A 77 litre tank is going in to the spare wheel cavity, and an additional 100 litre tank is going across the back of the boot - against the rear seat. As LPG tanks can only be filled to 80% capacity, this gives me about 140 litres of LPG. LPG is marginally less efficient that petrol, but the LPG tanks will still give me a range of about 900 miles.

The good news is that the guys who are doing the conversion also sell the LPG at 35p a litre (discounted to those who have had their conversion done by them). So I will get about 900 miles for a cost of £49. This makes running my car for these huge mileages bearable.

I previously had a Mondeo converted, and ran it for 100 000 miles on LPG without a problem. There are real advantages to LPG, and as congestion charging is likely to start popping up all over the UK, and LPG vehicles are exempt, then that will be one more advantage.

Once I have run the S280 for a few months on LPG I'll post an update report for those who are considering the conversion.

 

[John Kerr]

Good idea.I'm thinking of going down that route myself in the future,will look forward to your updates.Twin Tanks? could be a lot of weight on the rear of the car.LPG is a liquid and is heavy

 

[BeeJay]

Good idea.I'm thinking of going down that route myself in the future,will look forward to your updates.Twin Tanks? could be a lot of weight on the rear of the car.LPG is a liquid and is heavy

The guys doing the work say they have used this solution before, and have converted the full range of S Class. The extra weight is largely over the rear axle, so should not be a problem - and I will also be running with a near empty petrol tank. I'll lose the weight of 80 litres of petrol, and gain the weight of 140 litres of LPG.

As promised, I'll post when I have run it for a month or two and let you know how it has worked out.

 

[Devonian]

I have done about 20,000 miles so far on my LPG conversion with no problem. almost got the cost of the conversion back now

 

[BeeJay]

I have done about 20,000 miles so far on my LPG conversion with no problem. almost got the cost of the conversion back now

That's good to hear, as some sources have said that MB cars hare problematic when converting to LPG. Certainly the guys I am using have done 1200 conversions and seem to really know what they are doing.

When I did an initial visit I was introduced to the staff saw the workshop and taken in to the stock room to see the equipment they use (Prins mostly). Before I left I was happy enough to book it in for the conversion.

I reckon to get the cost of the conversion back in about 12 months.

 

[jibcl500]

Personally not a fan of LPG especially on an all alloy engine, LPG is to dry and some engines need lub from petrol and a little carbon build up.

How many MB's needed a head skim and new gasket over none LPG MB's, quite a few I should imagine.

LPG also runs hotter than petrol, range rovers 3.9 and 4.2 engines where never good long term on LPG, Ive sold 50 engines to LPG users because the engines failed running on LPG. Problems where bent heads, cracked heads, slipped liners, cracked blocks, poor running on petrol, back fires through the induction system destroying MAF's air boxes, sorry but engine designers built engines to run on petrol don't take into consideration things LIKE LPG. Ok it can run on it but not long term.

Dont like it and would never recommend it, I cant even see the benifits financially either, how many miles does one have to do before the LPG conversion is paid for????

What service or repair costs have been incurred because of LPG????

£2000 repair bill because of LPG on top of a £2000 conversion, thats a lot of miles before a profit.

Sorry I hate LPG, I hate the conversions because they make nice motors look cheap, AND I hate the fitters of these kits because they dont have the brain cells to understand that putting the LPG filler RIGHT IN THE MIDDLE OF THE OS REAR WING ON A CL ISN'T GOING TO MAKE THE CAR LOOK F££KING STUPID. People that do this kind of thing need a tatoo on their forehead, TAWT so they can remind themselves as to what they are!!!!!!

Sorry rant over bad day going to bed. Bollocks.


jib

 

[Cnics]

SO you'd recommend it then jib?

 

[kth286]

BeeJay

I guess your car is the W140 using the 104 straight six engine with the all electronic engine control using the HFM system.

I would be interested to know how they fit the additional injectors on this engine, because I am thinking maybe I might be going down this route too.

 

[wireman]

Beware of cowboy LPG conversion makers, they are prevalent and dont care about the life of their product or the vehicles to which they are fitted, maybe they need the same tatoo.
LPG promises much but to work well as on industrial fork lifts etc the engine is designed for LPG not petrol using much higher compression ratios among other things, they will run on petrol for cold weather starting etc but must run on LPG to last any time.
They are definatly a wee bit cleaner and dont dirty their oil as much but any claim of ecological superiority is I believe nothing other than greenwash of the extreme order.

If you see a petrol car on fire it is reasonably safe to watch from a fairly short distance, when a workshop with gas cylinders inside burns down the FB clear at least a 1/4mile radius, how will we cope with an LPG car fire?

 

[Devonian]

Well Jib's comments are certainly interesting. I'm not qualfied to neither do I have sufficient data to argue. I am running my first LPG converted vehicle and I did it partly for the reason of gaining first hand experience. It may be that your absolutely right and my engine packes up prematurely (I hope not).
However on the cost front (How many miles do you have to do to benefit) well that's just simple mathematics. In my case it will take about one year to recover my conversion cost (almost there).
If as you say i end up having to spend 2K on the engine then that's another years saving gone !. Time will tell.

As you have sold 50 engines to LPG users, was it because they were running on LPG or how many would have failed anyway? Presumably you do sell engines to petrol users as well? so do they fail also?
The above may sound like I'm trying to sell LPG, far from it I'm just debating the issue, Jib you could be quite right but on the other side of the coin I have spoken personally to many people who have covered 150 - 200K on LPG without problems.
I assure you if mine blows up I'll let you know.

 

[mlc]

Never having owned or driven a car with LPG I offer two observations:

If you want better fuel economy than an S280 why not just buy a diesel version,well proven technogy and covered by the MB warranty.

When I was looking for my S320 last year I kept finding two very cheap cars on auto trader. They were there for ever and cost at least £2k less than you would expect. They were both LPG converted S280's. Clearly no one wanted them.

Mark

 

[BeeJay]

BeeJay

I guess your car is the W140 using the 104 straight six engine with the all electronic engine control using the HFM system.

I would be interested to know how they fit the additional injectors on this engine, because I am thinking maybe I might be going down this route too.

Yes it is . I'll let you know

 

[BeeJay]

Never having owned or driven a car with LPG I offer two observations:

If you want better fuel economy than an S280 why not just buy a diesel version,well proven technogy and covered by the MB warranty.

When I was looking for my S320 last year I kept finding two very cheap cars on auto trader. They were there for ever and cost at least £2k less than you would expect. They were both LPG converted S280's. Clearly no one wanted them.

Mark

I am not too worried about the possible problems of selling them on as I intend running my S280 for another couple of hundred thousand miles (LPG conversion allowing ;-]]

 

[BeeJay]

Never having owned or driven a car with LPG I offer two observations:

If you want better fuel economy than an S280 why not just buy a diesel version,well proven technogy and covered by the MB warranty.

When I was looking for my S320 last year I kept finding two very cheap cars on auto trader. They were there for ever and cost at least £2k less than you would expect. They were both LPG converted S280's. Clearly no one wanted them.

Mark

Having driven 100 000 miles oin a LPG car, then the next car was a diesel (another 100 000 miles) I preferred the LPG.

Always the risk that the government will increase the duty and make it less attractive. However, making what is seen as 'green' fuel more expensive is probably politically unlikely - at least for the moment.

 

[BeeJay]

Beware of cowboy LPG conversion makers, they are prevalent and dont care about the life of their product or the vehicles to which they are fitted, maybe they need the same tatoo.
LPG promises much but to work well as on industrial fork lifts etc the engine is designed for LPG not petrol using much higher compression ratios among other things, they will run on petrol for cold weather starting etc but must run on LPG to last any time.
They are definatly a wee bit cleaner and dont dirty their oil as much but any claim of ecological superiority is I believe nothing other than greenwash of the extreme order.

If you see a petrol car on fire it is reasonably safe to watch from a fairly short distance, when a workshop with gas cylinders inside burns down the FB clear at least a 1/4mile radius, how will we cope with an LPG car fire?

True some cowboys about, but they tend not to last. These guys have been around for at least the last seven years, and having trawled the web and any forums I could find on the subject I could not find a bad word about them.

Yes, the green credentials of LPG are a little suspect as the CO2 emissions are no better, although better on Hydrocarbons and Nitrous Oxides, and certainly a lot better than diesel.

 

[BeeJay]

Personally not a fan of LPG especially on an all alloy engine, LPG is to dry and some engines need lub from petrol and a little carbon build up.

How many MB's needed a head skim and new gasket over none LPG MB's, quite a few I should imagine.

LPG also runs hotter than petrol, range rovers 3.9 and 4.2 engines where never good long term on LPG, Ive sold 50 engines to LPG users because the engines failed running on LPG. Problems where bent heads, cracked heads, slipped liners, cracked blocks, poor running on petrol, back fires through the induction system destroying MAF's air boxes, sorry but engine designers built engines to run on petrol don't take into consideration things LIKE LPG. Ok it can run on it but not long term.

Dont like it and would never recommend it, I cant even see the benifits financially either, how many miles does one have to do before the LPG conversion is paid for????

What service or repair costs have been incurred because of LPG????

£2000 repair bill because of LPG on top of a £2000 conversion, thats a lot of miles before a profit.

Sorry I hate LPG, I hate the conversions because they make nice motors look cheap, AND I hate the fitters of these kits because they dont have the brain cells to understand that putting the LPG filler RIGHT IN THE MIDDLE OF THE OS REAR WING ON A CL ISN'T GOING TO MAKE THE CAR LOOK F££KING STUPID. People that do this kind of thing need a tatoo on their forehead, TAWT so they can remind themselves as to what they are!!!!!!

Sorry rant over bad day going to bed. Bollocks.


jib

Trying not to sound defensive (honestly)

Can't comment on alloy engines and lubrication - perhaps an MB specialist might throw some light on this ?

"How many MB's needed a head skim and new gasket over none LPG MB's, quite a few I should imagine." - sounds a little speculative, does anyone have the facts ?

You will certainly see more cars than me. However, at least some of the engine failures you have seen would have happened whether there was LPG fitted or not. I wonder in how many of the cases there was a relationship between cause and effect ? I certainly had no problems in 100 000 miles and a number (admittedly small) of friends have had similar positive experiences.

Financial benefits are obvious at 35p a litre as opposed to 97p

LPG systems, in themselves, need little servicing and any garage I have spoken to are not concerned whether there is an LPG system fitted or not.

I trust the guys working on the car, but as promised I'll keep the post up to date when I have had the car back for a while.

 

[jibcl500]

Range rover engines are actually quite a good engine, ok the design is 50 ish years old there abouts and its been redeveloped over time but reg oil changes and sensisble use means a 3.9 could go on for 300k if not more like any engine given good servicing. Look for 4.6 RR's with LPG and see how many have had engine changes compared to none LPG RR's

The demand for the 4.2 V8 for the LSE was enormous, first question I would ask is are you ruinning it on LPG "yes" was always the answer.

Some engines will be good on LPG for many miles, lack of servicing on the LPG will also be a downfall, Petrol has additives in it that help engines, LPG doesnt.

Engines with cast blocks and alloy heads would fair better on LPG all alloy engines dont.

Personally I dont care if someone wants to fit or use LPG its thier choice, me I'd never touch a car thats got LPG fitted.

Heres one for Malcolm, tell me what you know about petrol engines running on H2O ????????? I been doing some research and its quite interesting.

not such a bad day today but bollocks all the same, oh and LPG is still a crap idea.

jib

 

[MotardMan]

Jib, you still causing trouble on the rangie.com list? Remember the "gay car" list thread? LOL!

One of the reasons I got shot of my 83 RRC was that it was too costly to run. LPG was considered, but rejected when a mate running LPG on his 3.5 EFi RRC had overheating problems caused by a badly installed and tuned LPG system. We ended up rebuilding the heads, and the car is better now, but TBH, I reckon the LPG killed the motor. If you are going to run LPG, make sure you employ the best advice, installer and servicing regime you can afford. LPG will stress your ignition system, if it is not spot on, prepare yourself for a big bill. Back fires, lean running, AFM or MAF damage, valve seats, bore washing, plug overheating can all ruin your lovely MB. Or any other car for that matter. As others have said, LPG can be trouble free, but it has to be a great setup, and looked after. No way is LPG maintenance free!

Correctly installed and serviced (both LPG and the rest of the car) an LPG system can have benfits for big milers. Just be aware of the potential for damage, and make sure it never happens to you.

;o)

Jim

 

[jibcl500]

Jim

Cant remember the gay topic, did I manage to upset anyone? if so good!!!!!

jib

No offense meant as I think my dogs gay and I still love him.

 

[kth286]

BeeJay is NOT fitting it to an all alloy engine.

The latest LPG systems for all electronic engines are very sophisticated and are a world away from the "blowback problem" types fitted to old fashioned engines of yor.

They have a facility to squirt a little lubricant into the mix if required also.

Note that Mercedes themselves produce new factory LPG cars nowadays, for certain markets, so the technology has been proven.