Fuel Economy

[LeStempy]

Don't worry Bob, I think he has shown his true colours.

 

[Reverend RobP]

Fucks sake it's like been in a school play ground!
@Hallam your comment has been removed. Any more directly offensive comments aimed at members will not be tolerated!!
@Stempyuno please stop with the to and fro comments towards Hallam now.

Anyone else please stop jumping on the back of these comments!

 

[Adam&Heidi]

Expect poor economy. Really. I'm not gonna lie to you.

They are a 2 tonne bus with pretty appalling aerodynamics and large engines. They are designed for comfort and luxury, not for cheap motoring.

As a brief run down:

E50 QD32 3.2 Diesel - 26mpg average. 18mpg around the doors. 36mpg on long runs at 55.

E50 ZD30 3.0 Diesel - 28mpg average. 20mpg around the doors. 40mpg on long runs at 55.

E50 VG33 3.3 V6 - 18mpg average. 14mpg around the doors. 28mpg on long runs at 55.

E50 VQ35 3.5 V6 - 16mpg average. 12mpg around the doors. 28mpg on long runs at 55.

E51 VQ25 2.5 V6 - 22mpg average. 18mpg around the doors. 32mpg on long runs at 55.

E51 VQ35 3.5 V6 - 20mpg average. 16mpg around the doors. 30mpg on long runs at 55.

These are worst case scenarios. If you are getting less than this, you have a problem (either with your engine or your right foot). If you go into buying an Elgrand with these figures in mind, then you won't be swearing 6 months down the line when you are on first name terms with every petrol station attendant within 30 miles of your house.

Thank you for these figures very helpful. I'm still to try Power mode, I'm thinking it's gonna be very thirsty.

 

[LeStempy]

It's stop start driving that does the damage. Even cruising at 80mph mine will sit around the 20mpg mark.

 

[Mickyc]

Around 72 litres iirc.

The 93litre (actual capacity) LPG tank I fit on Elgrands holds 85 litres (net, allowing room for expansion) of LPG... More range on LPG than range on petrol, over double the range of a standard Elgrand. But with an LPG conversion the usual idea is to run on LPG as much of the time as possible (avoid running on petrol) because LPG is half price of petrol. Although some owners have also valued the additional range highly.

Hi. Out of interest whats the average turn around time for a conversion. Also where does the spare wheel go? I want to get an Elgrand but it will be used as a mixture of everyday short journeys and long distance tours around uk and europe.

 

[Lpgc]

Hi. Out of interest whats the average turn around time for a conversion. Also where does the spare wheel go? I want to get an Elgrand but it will be used as a mixture of everyday short journeys and long distance tours around uk and europe.

It takes me 2 long days to convert an Elgrand... If (say) one is dropped off for me to convert at 10am on a Monday morning I will have it converted by around 8pm on the Tuesday. But I like to run some additional checks on the Wednesday morning because following calibration on the Tuesday the Wednesday morning is the first chance to see the engine warm up from cold and switch automatically to Lpg. The Wednesday morning checks are not strictly necessary but I sometimes make minor adjustments then. Most customers who drop an Elgrand off on a Monday morning would collect on the Wednesday morning (or drop off on say Wednesday and collect on say the Friday) but Tuesday and Thursday (respectively) pickup would be OK except for being quite a late pickup.

Some people carry the spare in the luggage area, some don't bother carrying a spare at all. Some (who don't carry a spare) carry a can of instant tyre repair aerosol and a mini 12v compressor. Most Elgrands come with a space saver spare wheel, which is probably an advantage over a full size spare if you want to carry a spare in the luggage area. My Elgrand space saver spare wheel lives in my caravan, I don't usually bother carrying a spare, people have different takes on it.

 

[Adam&Heidi]

Thanks for info

 

[Lpgc]

I've just skimmed through some posts from a couple of weeks ago on this thread

@Briselgrand A few years ago here in the UK there were a few companies offering a conversion that gave a diesel lpg mix to help reduce running costs for the white van brigade but I don't think it realy took off

It is possible to fit an LPG system to add a bit of LPG to the mixture during running on diesel, i.e. to supplement diesel fuelling with the addition of a bit of LPG.

You couldn't really call it 'an LPG conversion' on a diesel engine because the diesel engine will always need to run on by far the majority of diesel, it can never run on LPG alone.

Not all such systems could be called 'fumigation' systems. Only systems that use a gas carb / LPG mixer type system on a diesel engine could be called fumigation systems, such systems would be more suitable to older diesel engines than more modern diesel engines. Modern diesel engines should be fitted with an LPG injection system, injection systems are not called fumigation systems.

Depending on the spec of the diesel engine it may be able to run on up to 30% LPG (so 70% diesel).

One of the benefits of adding LPG to the mix on an engine running on diesel is that it increases the overall efficiency of the diesel engine (and lowers emissions at the same time). Older design diesel engines are less likely to be as efficient as newer design diesels, smoke and particulate emissions from a diesel engine are unburned diesel. Adding LPG to the mix can see more of the diesel burn fully inside the engine where it will do useful work rather than go out of the exhaust having done no work. So addition of an LPG system can be more beneficial on an older design diesel engine than on a newer design diesel engine.

The problem for adding LPG to the mix on a diesel engine is that too much LPG can cause 'star fire' which is a bit like pinking on a petrol engine. Starfire can destroy a diesel engine, there is a fine line between maximising savings by running a diesel engine on as much LPG (and little diesel) as possible and going too far and causing starfire.

Modern LPG supplementation systems for diesel engines are fully configurable/programmable to inject the correct amount of LPG over the full range of the engine's operating conditions, and are fitted with extra sensors such as exhaust gas temperature sensors to further reduce or shut-off LPG addition if a problem is noticed.

A diesel engine will produce more power with the addition of LPG. But if the extra power is used the engine will use more fuel than it would without the LPG addition, it will still use the same amount of diesel but will use LPG at the same time. If the extra power isn't used it will be cheaper to run because less diesel than usual will be used due to the partial fuelling by LPG while at the same time the LPG makes the diesel that is used burn more efficiently.

The 'but if the extra power is used' point is perhaps the reason we don't see many diesel vans or fleet vehicles fitted with LPG... Bosses know that drivers likely would use the extra power when bombing up and down the motorway at 90mph in Sprinters etc and bosses would end up with a higher fuel bill rather than lower. But for private owners that pay for fuel themselves and don't bomb around at 90mph good savings are available... But not as good as the savings from converting a petrol vehicle to LPG.

 

[Elgrand the big boy]

My power mode keeps activated its self when I put food down keeps coming on after pressing it off.

 

[LeStempy]

Is that a bad thing?

 

[Elgrand the big boy]

Well it's on when I turn it off but trying to test mpg on new route from work

 

[Lpgc]

My power mode keeps activated its self when I put food down keeps coming on after pressing it off.

They do momentarily go into 'Power' mode when you put your foot down, that's normal.

 

[Breadman23]

When you boot it the power does come on until you release the throttle,then should go off

 

[Elgrand the big boy]

They do momentarily go into 'Power' mode when you put your foot down, that's normal.

Haven't noticed it before a costly surprise and booted it round the roundabout aback end happy

 

[Ianm68]

Had a Range Rover 4.4 V8 that was an LPG conversion, couldn't have kept it on the road if it wasn't! Looking at converting the Elgrand, has anyone else done this?

yes I've done it but I am on my 3rd engine! My garage that has changed the engine twice says its something to do with running on LPG although i know other Elgrands have been converted, ... considering it again as the tanks are still there and my drive down through France recently cost and arm and a leg! I believe some systems are better than others....

 

[JohnK]

yes I've done it but I am on my 3rd engine! My garage that has changed the engine twice says its something to do with running on LPG although i know other Elgrands have been converted, ... considering it again as the tanks are still there and my drive down through France recently cost and arm and a leg! I believe some systems are better than others....

Sorry to hear you've had two engines go! Theres a lot of us on here who run and lpg without blowing our engines! I'm sure our resident expert @Lpgc will be able to provide more info but I would think the explanation from your garage is not to be trusted unless the lpg installation is particularly bad. Have you had your cats done? If not that is far more likely to cause problems.

 

[Lpgc]

yes I've done it but I am on my 3rd engine! My garage that has changed the engine twice says its something to do with running on LPG although i know other Elgrands have been converted, ... considering it again as the tanks are still there and my drive down through France recently cost and arm and a leg! I believe some systems are better than others....

LPG is better for your engine than petrol as long as it's not been totally bodged. Which firm converted your Elgrand? E50 or E51 (your profile says E50)? 3.3 or 3.5? What did the garage say was blown about your engines?

 

[deemartin]

Hi Stevie,

Same £1595.

If we know £1595 and 7000 miles per year, we just need to know average mpg to calculate payback time.

Suppose you get 20mpg, that's 350 gallons, if petrol is £1.20 per litre that's £1911 per year on petrol.

If LPG is half price (60p) that'd be £955.50 per year but you use a bit more (say 10%) LPG than you would petrol, then again it depends on the price you can buy LPG.. You can buy it at far less than 60p some places, but let's assume 60p and you use 10% more. So now you use £955.5+10% = £1052 of LPG in a year. Actually you'll use a small amount of petrol during the brief engine warmup period too, so call it £1100. So 1595/1100 = 1.45 years = 17.4 months.

Converted about 20 Elgrands so far this year, got another coming for conversion on Monday, another the Monday after, 2 coming the week after that! Got Elgrands booked in through October and November too but not fully booked up, could fit other Elgrand conversions in during that time.

Thanks,

Simon

Hi Simon
Thanks for your LPG info. I'm about to buy a 2010 (60) Nissan Elgrand 2.5 sight unseen whilst its still on the high seas. I intend converting it to dual fuel using the spare wheel space for the LPG tank.
However, from a photograph of the open rear door, I can't see if this model has a spare. Do you know if the E52 2010 (60) model has a spare wheel locker and, if not, can it be placed elsewhere. I intend to convert the Elgrand into a camper so space will be a premium!

 

[Kenzie (Mary Poppins)]

Hi Simon
Thanks for your LPG info. I'm about to buy a 2010 (60) Nissan Elgrand 2.5 sight unseen whilst its still on the high seas. I intend converting it to dual fuel using the spare wheel space for the LPG tank.
However, from a photograph of the open rear door, I can't see if this model has a spare. Do you know if the E52 2010 (60) model has a spare wheel locker and, if not, can it be placed elsewhere. I intend to convert the Elgrand into a camper so space will be a premium!

How far off the beaten track do you intend to go buddy

 

[origami]

I only get 14 mpg average in city with E51 2.5 V6