LPG Conversion Advice - 1987 Fiat Ducato

[hideyspidey]

HI

We have a 1.9l Fiat Ducato. We were told it was 23-25 MPG. However we are getting 19mpg and this is causing us some concern.

When we bought it we discussed putting an LPG conversion on, but the seller said that as its old it wont make a difference. I am unsure about this as as i had a 1992 ford mondeo for long trips with LPG and it was fantastic.

As the engine is old we want to know if it will make a difference? We cant afford to run it at 35p a mile for ever but we can afford an LPG conversion eventually. We will get it all done properly.

My question is, can we do it and is it worth it, or is the engine too old and of the wrong build?? It has 45k on the clock.

Please help as we have only had a week, are going local this weekend but thinking we cant afford her any more

Thanks

[Derek Uzzell]

I thought the LPG question had been fully covered in replies to your earlier inquiry.

 

If you bought the motorhome believing it would return 23-25mpg and are now concerned that a 19mpg fuel consumption means you won't be able to afford to run it, you'd be very unwise (or startlingly optimistic) to be considering paying the considerable cost for an LPG conversion. As George Collings said, converting carburettor-equipped vehicles to LPG isn't always satisfactory and the cost of the conversion may never be recouped.

 

I would have thought 23-25mpg should be achievable generally, but 19mpg doesn't seem too outrageous to me and might be anticipated if you were using the vehicle on short runs or around town, or making no attempt to drive an elderly, petrol-fuelled vehicle for maximum fuel economy.

 

The first thing to do is to ensure that the motor is providing optimum performance and that simple things (like a dirty air filter) aren't increasing fue consumption.

 

Tuning the 2litre motor is discussed here

 

http://www.jktowers.fsnet.co.uk/motorhome/performance_tuning.htm

 

The "Before you start" section advises "Check / Address all usual culprits that result in reduced performance". Anything that reduces performance will increase fuel consumption. So, before you waste your money on an LPG conversion, or conclude that you won't be able to afford to run the Murvi because it's only doing 19mpg, make certain that everything that can have an impact on fuel consumption/performance has been properly investigated.

 

(What tyre pressures are you using? If these are badly too low, this alone can increase fuel consumption.)

[hideyspidey]

Thaks, i just wanted to know if converting to LPG will be worth it in the long run. We bought as we like to travel all over and drive around europe

If were still gonna get the equivalent MPG on LPG then theres no point

[pepe63xnotuse]

Although admittedly not great,19mpg isn't too bad for 26 year old, 1.9 ltr petrol, that's pulling around a large and quite heavily loaded, vehicle...

 

(I know it's larger/heavier but our 2008 diesel Renault will drop down to that, if I'm getting a wriggle on ;-))

 

..and don't let yourself be too influenced by some of the nonsensical MPG figures that some say they get from their aging vehicles.I've read on some forums,folk claiming figures that a small, modern hatchback would be lucky to achieve. *-)

 

Just spend some money giving it a thorough service/tune/fettle....and then, MPG-wise, it does,what it does.. ;-)

[Derek Uzzell]

There's a 'savings' calculator here:

 

http://www.autogas.ltd.uk/benefits/savings-calculator/#

 

A 1994 MMM magazine report on a 4-year-old Ford-based Auto-Sleepers Legend motorhome with 2-litre petrol engine quoted an averaged 19.84mpg over 17,000 miles. Although the motors are different, I would have thought it should be possible to achieve 23-25mpg with a smaller, lighter 1987 Murvi as long as everything is working efficiently.

 

Potential cost savings from autogas usage stem from the price-difference between LPG and petrol. Received wisdom seems to be that BY VOLUME the mpg of a vehicle running on autogas will be inferior (by perhaps 20%) to the mpg attained when the vehicle is running on petrol.

[Dave Newell]

I used to run a 1990 Talbot Express based Highwayman with the 2 litre petrol motor and generally averaged around 22-23 mpg. The Highwayman had a GVW of 2900KGs but with a coachbuilt body it had the aerodynamics of a shed! A Murvi being a panel van conversion should be capable of matching or bettering my consumption figures if driven economically. Don't forget you've only got 84BHP to play with, well you would have had in 1987, how many of those ponies have run off in the intervening years only a rollinmg road session could tell.

 

It can be a real problem going from a relatively modern car with good fuel consumption to a much larger vehicle from two and a half decades ago, the modern car will have much more power available and give much better fuel consumption than the quarter of a century old motor with a house on its back. Don't forget that even a panel van camper is effectively a vehicle with a small house attached, snails are slow for a reason.

 

Get it serviced and tuned properly and drive it gently, the camper and your bank balance will thank you.

 

D.

[hideyspidey]

Thanks, excellent advice