V6 LPG Conversions - any recommendations

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Simon Jones
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V6 LPG Conversions - any recommendations

Post by Simon Jones » Mon Jan 26, 2009 11:43 pm

I have a crazy idea about buying a V6 & getting an LPG conversion fitted & then using it to commute 500 miles a week. Hopefully, I can talk myself out of this :? but I have two questions:

1) Insurance premiums. I've heard that there can be an increase in insurance due to the more 'explosive' nature of the gas tanks. Has this affected anyone?

2) There's a comment on Honest John's website http://www.honestjohn.co.uk/carbycar/index.htm?md=1024: "There are LPG conversions on the 2.5 V6 petrol which should be avoided. The Japanese valve assembly does not like LPG and the valves burn out over time". I've heard about fitting a lube system - will this help with this problem?

Thx in advance.
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Re: V6 LPG Conversions - any recommendations

Post by mikeonb4c » Tue Jan 27, 2009 12:09 am

Apole (V6 with LPG conversion) mounted a stern defence over it being OK to fit LPG. He has a flashlube system (I think its called) installed. No doubt he'll read this and comment but PM him if not. Honest John could be Ignorant John in this case :lol:
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Re: V6 LPG Conversions - any recommendations

Post by madmile » Tue Jan 27, 2009 12:17 am

Both valid comments (possibly) but what would be more likely to put me off, is the extreme likelyhood that 2 months after your conversion the government would change the tax on lpg and make the price equivalent to petrol.
I know a few people with lpg conversions (not bongo) and they never seem to be trouble free.
Much as I like bongos, if I had to commute 500 miles a week, I would choose something else - unless of course you are planning to sleep in it during the week - then it could make sense.
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Re: V6 LPG Conversions - any recommendations

Post by Regor » Tue Jan 27, 2009 12:32 am

Hi Simon,

I run an N plate V6 and had an LPG conversion done in September 2008 by Barry at BPV Autogas in Slough. (Prins VSI system, regarded as the best in the world)

I'm very happy with the conversion and have no hesitation in recommending this company =D> . Took it back last Friday for the 1st sevice (1500 miles) and it now goes even better than before :D :D At 50.9p per litre with equal performance and economy as on petrol it just makes my Bongo grin even bigger!! (When was the last time you smiled when filling up)

It is recommended that you have a 'flash lube system' fitted as this sorts out the Mazda soft seats and valves, and the spin off is that it coats the inside of the exhaust sytem with an oil film thereby slowing down corrosion.

A good LPG system is not cheap, but it is an investment in a quality product backed and supported by excellent knowledge from the team at BPV. Payback distance is reckoned to be between 14 - 16,000 miles so if you are looking at 500 miles per week then you will recoup your investestment very quickly.

I'm insured with LV and they made no change to my premiums following the LPG conversion.

Hope this answers some questions for you, but ask away as I'm sure you will have more.

Best regards
Roger
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Re: V6 LPG Conversions - any recommendations

Post by mikeonb4c » Tue Jan 27, 2009 12:41 am

madmile wrote:Both valid comments (possibly) but what would be more likely to put me off, is the extreme likelyhood that 2 months after your conversion the government would change the tax on lpg and make the price equivalent to petrol.
I know a few people with lpg conversions (not bongo) and they never seem to be trouble free.
Much as I like bongos, if I had to commute 500 miles a week, I would choose something else - unless of course you are planning to sleep in it during the week - then it could make sense.
Ed's post has a worrying ring of plausibility and sense about it. I have always wondered how LPG remained so much cheaper, and just hope it continues that way. But you can't rely on much these days (look at us dieselheads with our brief holiday on veg. oil :(

I wonder how good a conversion you could manage on a Kangoo :roll:
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Re: V6 LPG Conversions - any recommendations

Post by Ron Miel » Tue Jan 27, 2009 1:12 am

mikeonb4c wrote:
madmile wrote:Both valid comments (possibly) but what would be more likely to put me off, is the extreme likelyhood that 2 months after your conversion the government would change the tax on lpg and make the price equivalent to petrol.
I know a few people with lpg conversions (not bongo) and they never seem to be trouble free.
Much as I like bongos, if I had to commute 500 miles a week, I would choose something else - unless of course you are planning to sleep in it during the week - then it could make sense.
Ed's post has a worrying ring of plausibility and sense about it. I have always wondered how LPG remained so much cheaper, and just hope it continues that way. But you can't rely on much these days (look at us dieselheads with our brief holiday on veg. oil :(

I wonder how good a conversion you could manage on a Kangoo :roll:
Whereas I agree with Roger. As I understand it (can't recall the exact date off-hand) the duty rebate is guaranteed for the next two or three years at least. Unless by then everybody had switched to LPG, obviously not at all likely, the incentive for the government to continue to encourage LPG adoption will still be there then, and even if duty increase begins, it's likely to be in stages at worst. Meanwhile, with 500 miles per week commuting, an LPG conversion would be more than paid for in the first year*. Also, if long-range without refuelling would be useful in those long commutes, the combination of both petrol and LPG tanks gives just that.

*(and don't overlook the better emissions, even if duty does sooner or later increase - that's the reason for the rebate, meanwhile, of course)

Honest-John-as-Ill-informed-John has recently been debated in this context (Bongo V6/LPG) in another thread, with that general conclusion. Flashlube should be fitted (and is, by any reputable LPG installer - although do ask), and eliminates the valve issues. Other earlier LPG system problems have been ironed out in current more refined multi-point systems. Ours (BiGas in a V6) certainly produces that big grin without a downside.

Vehicle LPG tanks are very strong high impact resistant steel pressure vessels, reckoned to be safer than most vehicle petrol tanks, many of which are made of plastic in modern cars - although not in the Bongo, of course. Also, whereas petrol tanks are usually "dumb", vehicle LPG tanks have integrated "smart" control systems which, among other things, automatically shut off both their input (filler) and output valves, on switching off, switching to petrol, auto-switching to petrol on LPG run out, or on violent decelaration/impact.

No increase in insurance at Safeguard, as long as properly installer-certified.
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Re: V6 LPG Conversions - any recommendations

Post by scanner » Tue Jan 27, 2009 12:44 pm

mikeonb4c wrote:Honest John could be Ignorant John in this case :lol:
He all too frequently is........................ :roll:

Ohh and I don't know if it matters, but you won't be able to use the Chunnel.
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Re: V6 LPG Conversions - any recommendations

Post by Simon Jones » Tue Jan 27, 2009 2:15 pm

Thanks for your replies - all good valid points (as normal). The situation is that I will be getting a car allowance soon & could either put the money towards something sensible to get me from A to B, or sell the current Bongo & put the money towards a newer model that I could get more use out of. The only downside would be putting such a high mileage on my pride & joy, so I would probably end up buying a cheap runaround car to share the load a bit. So many choices...
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Re: V6 LPG Conversions - any recommendations

Post by The Great Pretender » Wed Jan 28, 2009 1:01 am

Simon Jones wrote:Thanks for your replies - all good valid points (as normal). The situation is that I will be getting a car allowance soon & could either put the money towards something sensible to get me from A to B, or sell the current Bongo & put the money towards a newer model that I could get more use out of. The only downside would be putting such a high mileage on my pride & joy, so I would probably end up buying a cheap runaround car to share the load a bit. So many choices...
Well here is my pennyworth. Stuff sensible, if im driving 100mls a day I wanna do it in a Bongo not a C1. :wink:
Before I got my Bongo I looked at getting a V6 and using LPG. If I hade gone down that route I would have fitted it myself and got it certified as it isn't rocket science. The V6 has 'soft valves' that need lubrication that LPG dosn't provide, one system that I looked at found a clever way around it by firing the petrol injectors for around 5 or 10% of the fueling. :wink:
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Re: V6 LPG Conversions - any recommendations

Post by Ron Miel » Wed Jan 28, 2009 11:03 am

The Great Pretender wrote:
Simon Jones wrote: The V6 has 'soft valves' that need lubrication that LPG dosn't provide, one system that I looked at found a clever way around it by firing the petrol injectors for around 5 or 10% of the fueling.[/color] :wink:
That's a nice one - do you still have the details for others who might consider LPG, as one downside (for me, anyway) with Flashlube, is the unreasonable but nagging fear that I'll forget to look at it in my weekly checks sometime, so will run out, and the engine will then immediately melt. OK, I admit it, I'm a hypochondriac, as far as baby Bongo is concerned.

Might interest other peeps to know that modern multi-point LPG systems electronically switch just one cylinder at a time (per full engine cycle, I guess) from petrol to LPG and vice versa, so there's always a smooth transition. What you describe is just a logical extension of those "smarts", and I should think it works fine, although some empirical data would be good, if you can identify it.
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Re: V6 LPG Conversions - any recommendations

Post by The Great Pretender » Wed Jan 28, 2009 11:26 pm

Sorry Ron, I did have the site on my list of favorites untill Friday when my puter went t*ts up and I lost my C drive, also lost my e-mail address book ](*,)
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Re: V6 LPG Conversions - any recommendations

Post by Ron Miel » Wed Jan 28, 2009 11:38 pm

The Great Pretender wrote:Sorry Ron, I did have the site on my list of favorites untill Friday when my puter went t*ts up and I lost my C drive, also lost my e-mail address book ](*,)
No worries GP - least of your problems. Commiserations!!
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Re: V6 LPG Conversions - any recommendations

Post by Ron Miel » Thu Jan 29, 2009 1:04 am

Ron Miel wrote:>
>
.....As I understand it (can't recall the exact date off-hand) the duty rebate is guaranteed for the next two or three years at least. Unless by then everybody had switched to LPG, obviously not at all likely, the incentive for the government to continue to encourage LPG adoption will still be there then, and even if duty increase begins, it's likely to be in stages at worst.....
>
>
Anyone notice that Lord (my life!) Mandelson, when introducing his scheme to bail out the motor industry with my money, yesterday, stressed the primary justification as a need to ensure there would still BE a UK motor industry, to lead the government's drive for lower carbon emission/greener motoring solutions. Difficult to then penalise the few of us who've already firmly gone in that direction, when everybody else still needs encouragement, don't you think?
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Re: V6 LPG Conversions - any recommendations

Post by apole » Mon Feb 02, 2009 12:29 pm

Hi Simon,

Sorry for the slow reply, been working in sunnier climes, it's tough but someone had to do it....

Anyway, most of your questions have been answered. There are dedicated LPG forums, take a look round those.

There are many questions to consider. If you get a good LPG system and get it fitted and serviced by people that know what they are doing, then you will find it reliable. As with all things, there are many systems and fitters out there that are not up to the mark, and as a result many stories of problems. There LPGA (industy regulator) basically does sweet fanny adams over poor installers so they get away with it.

If you want more details on what system, tank, regulator etc to choose then PM me and I'll be happy to help/explain.

Onto the main question though. For me the LPG makes the bongo cheaper to run which is good as I like using it. However, for my day to day running, I have now got a smaller 2nd car. Yes it's LPG again, this time I chose one that was fitted by the main man himself at the Prins distributer, so no worries there, and someone else paid for the conversion. It costs me 4p a mile on fuel, £15 a year road tax, and just over £100 for insurance. I could even tow it behind the bongo on a custom A frame if I was daft enough !! Congestion charge is also free too once you register so if you head into the C zone that could save you.

It's a tough decision with many things to consider, the bongo is a nice car to drive but even on LPG you are looking at 12p a mile on fuel, and outlaying nearly £2k for an LPG install. I'd be leaning towards a smaller 2nd car with low tax etc and it can be more easily maintained/repaired.
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