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lpg removal help
Posted: Mon Dec 01, 2008 4:14 pm
by 320ise
sorry to ask this but can anyone list all the parts i need of the donor car (e36 318i m40) single point system.
i see a few parts that are not std in the engine bay, that are easy removal, as for wire/ecu where is this likley to be located? or is it worth getting all the major parts tank pipes etc and buying new wiring?
novice to lpg so pics would be a great help, sorry to be a pain lol!
Re: lpg removal help
Posted: Mon Dec 01, 2008 6:49 pm
by cecotto479
TBH a single point system isn't worth the bother removing. The car will be significantly down on power and will get about 75% of the mpg on gas that it does on petrol.
A sequential multipoint system will be virtually undetectable in driving and give you 95% of the power and economy. It might be worth gettib#ng the tank and piping and vapouriser, and buying the rest of a multi point kit new. You need to have it certified by an member of the LPGA before you can MoT it, I believe.
Re: lpg removal help
Posted: Mon Dec 01, 2008 8:56 pm
by StuBeeDoo
cecotto479 wrote:TBH a single point system isn't worth the bother removing.
Rubbish!cecotto479 wrote: The car will be significantly down on power
It will be slightly down on power. I defy any normal driver to truthfully say they can tell any difference in performance on the road.cecotto479 wrote:and will get about 75% of the mpg on gas that it does on petrol.
It's more like 80% and with the difference in cost between petrol and LPG it still works out as a significant saving.cecotto479 wrote:A sequential multipoint system will be virtually undetectable in driving and give you 95% of the power and economy.
A sequential system on an E30 is unnecessary extra expense and extra time/effort to fit.cecotto479 wrote:You need to have it certified by an member of the LPGA before you can MoT it, I believe.
Not true. Certification is not necessary, many insurers don't ask for certification even though you do have to declare the LPG system as a modification. The LPG system is not tested at MOT. You wouldn't believe how many LPGA accredited installers don't have a clue about the fitting guidelines. Many LPGA members appear to be full of s**t.
Re: lpg removal help
Posted: Mon Dec 01, 2008 9:02 pm
by Jon_Bmw
Hmm 95% of the power might be difficult considering LPG has a 10% less calagorific value than petrol.
Cecotto have you been speaking to an LPGA installer who is running low on business?
Re: lpg removal help
Posted: Mon Dec 01, 2008 9:18 pm
by 320ise
can anyone answer my above questions (stubeedoo i was hoping you would view this as you appear to be quite clued up!) and jon_bmw sorry if this is another randomer! i am trying to stop posting random things lol!
Re: lpg removal help
Posted: Mon Dec 01, 2008 9:58 pm
by johnna
Be cool, it was a good question. I'm considering a similar path.
Re: lpg removal help
Posted: Mon Dec 01, 2008 11:02 pm
by cecotto479
Jon_Bmw wrote:......
Cecotto have you been speaking to an LPGA installer who is running low on business?
No. Just personal experience. And the garage who fitted mine are booked solid till March. Allegedly.
I had a single point system on an old Range Rover and it was shite. It wouldn't idle properly. It wouldn't run on gas until it was properly warm and it was noticeably down on power. On petrol it was as good any of the other 4 or 5 I had in stock at the time. On gas it was a hound, but it was a very, very cheap to run hound.
I've just had a new multipoint system fitted to the Jeep and it's amazing. It is indistinguishable from petrol in terms of performance and refinement.
I'm sure it's down to the computerisation of the engine management systems.
And while, by default, it starts on petrol and switches to gas, so much do I abhor waiting for it to change to gas,
("Come on you bastard, this is costing me 94p per litre. Change ya bastard. Change.") and even though it's usually changed before the first roundabout (and if you know where I live, that's not very far at all), I've taken to forcing it to start on gas.
I'm getting 16 on gas as an average and used to get 17 on unleaded. The 80 litre tank takes 72 litres thanks to a custom valving [s]bodge[/s] modification.
It's excellent.
My info on LPGA certification comes from "Wheeler Dealers" and "Practical Classics" magazine who have both featured DIY installs recently and both said they required to be tested.
I bow to your superior knowledge, but my experience says single point = shite and multipoint = brilliant. To be fair, the old RR was on carbs too - I suspect injection and electronic management systems have somehing to do with the improvement.
Re: lpg removal help
Posted: Mon Dec 01, 2008 11:52 pm
by Cloud
StuBeeDoo wrote:cecotto479 wrote: The car will be significantly down on power
It will be slightly down on power. I defy any normal driver to truthfully say they can tell any difference in performance on the road.
I can.
There's a steep hill around here, and on petrol I can make it all the way up to the top in 3rd gear. Running singlepoint LPG on the same hill, in the same vehicle, with the pedal rammed into the carpet with the same degree of force, I have to change down into 2nd and then 1st. The difference is significant when there's serious load, there's less grunt. But normally, you're right, if the car (or van in my case) is on a flat road, the difference is indistinguisable.
Re: lpg removal help
Posted: Mon Dec 01, 2008 11:56 pm
by Brianmoooore
Jon_Bmw wrote:Hmm 95% of the power might be difficult considering LPG has a 10% less calagorific value than petrol.
What on earth has the calorific value of the fuel got to do with power??????? You simply feed in more of the stuff, which accounts for the greater fuel consumption (by volume). If you measure the fuel consumption by weight, like they do with aircraft and ships, the fuel consumption is actually reduced.
Cecotto479 - If your Range Rover performed as you said, the LPG system quite simply wasn't installed or set up correctly, and membership of the LPGA by the installer is most certainly no guarantee that it will be!
I've been running an E30 325 for eight years on LPG, with a single point system, and the performance loss, if any, is undetectable.
With an E30 where the petrol system and management is past its best, there might actually be an increase in power! LPG certainly burns more efficiently than petrol.
I've never had the slightest trouble insuring a LPG converted vehicle without a certificate.
I've actually insured a fresh BMW this week, using the cheapest quote given by 'Go compare', and there has been no mention of certificates.
Re: lpg removal help
Posted: Mon Dec 01, 2008 11:58 pm
by Brianmoooore
Cloud wrote:I can
Then the LPG system is not installed or set up correctly!!
Re: lpg removal help
Posted: Tue Dec 02, 2008 12:06 am
by Cloud
Brianmoooore wrote:Cloud wrote:I can
Then the LPG system is not installed or set up correctly!!
That's possible. It's a bit rubbish.
Re: lpg removal help
Posted: Tue Dec 02, 2008 12:22 am
by cecotto479
Brianmoooore wrote:
Cecotto479 - If your Range Rover performed as you said, the LPG system quite simply wasn't installed or set up correctly, and membership of the LPGA by the installer is most certainly no guarantee that it will be!
It definitely did. It was a good while ago. It was a bit of an old dog anyway and I have no idea who fitted it.
It was cheap to run - that's it.
I am absolutely converted to the benefits with the Jeep though. I particularly love filling it up and getting change out of £30.
Re: lpg removal help
Posted: Tue Dec 02, 2008 12:27 pm
by Jon_Bmw
cecotto479 wrote: maximise mpg of the lpg. So I don't see why squirting extra lpg just so that you can attain slightly better performance is really that relevant.......Also, you don't pay for lpg by weight, you pay for it by litres.
Maximum power and economy are both achieved by running the engine on a stoichiometric mixture (approximately and simplified) of either fuel. To achieve this, you need to add more LPG (by volume) to a certain volume of air than you do petrol. The energy contained in the volumes of both fuels will be about the same, although the LPG will combust more efficiently.
In most applications you do buy LPG by weight. Unfortunately, one of them is road fuels. The density of LPG changes considerably with temperature, and there's a considerable advantage in buying autogas early in the morning from a forecourt with an above ground storage tank, following a cold night, than from one in the afternoon on a hot day.
Re: lpg removal help
Posted: Tue Dec 02, 2008 1:56 pm
by Brianmoooore
The above post is one of mine - not Jon_Bmw's!! John's post has disappeared, to be replaced by mine!!!!
I have no idea why or how!
Re: lpg removal help
Posted: Tue Dec 02, 2008 2:02 pm
by Jon_Bmw
And the small quote that shows as Cecetto, is actually me!
Brian, i think you pressed the edit button on my post rather than quote, sack this mod!

Re: lpg removal help
Posted: Thu Dec 04, 2008 1:56 pm
by johnlouis
I have to say that while a good single point LPG system can be unnoticable in drivability it is, in my experiance, more prone to "running like a dog". Mine sometimes runs really nicely, and other times stalls at every set of traffic lights. I am almost 100% certain that is down to the vaporiser, but anyway.
To answer the origional question, you want everything that is connected in any way, thus start with the tank, dont bother with the pipe or the wire from back to front unless it is easy to remove...
Make sure you get the vaporiser, solonoid valve with filter, mixer, ecu + switch (behind glovebox or in engine bay, follow the wires from the switch), fill point and any pipe fittings you can.
Interesting about ambient temp and LPG delivery, I will have to read up on this, though surly the meter, being of the flow variety and that LPG is transferred as a liquid, from the bottom of the tank, then one would assume this cant make that much diference?
Re: lpg removal help
Posted: Sun Dec 07, 2008 7:33 pm
by johnna
Re: lpg removal help
Posted: Sun Dec 07, 2008 7:39 pm
by Jon_Bmw
I see you have a couple of different(but probably the same gear) control units with stepper motors. I have always found it amusing the Leonardo ECU is used by so many companies who put their own name on it! AEB175 is one of the ones you have, and the other one is probably the same. You have two stepper motors as well. I can't really see enough information on the vapouriser to see if its suitable(got enough power kind of thing

)
Depending on the tank age, and from your naff photos

i'd say about £150-350.
Re: lpg removal help
Posted: Sun Dec 07, 2008 7:45 pm
by Jon_Bmw
Now I have helped you, my dad has come in with a 'good idea,' and you are the man to help.
He is middle aged, bored, has some money but likes being tight. He wants to see if me, my brother and him can go around Scotland and back in a weekend costing nothing. You guessed it, chip fatting.
I have done a bit of research in the past when I contemplated it. Bosch pump is essential I know, would I be right in saying most German manufacturers used them? Merc, audi etc? Do you think you could run 100% WasteVO that was filtered with tights? Obviously carrying a spare fuel filter and a jerry can of diesel.
Fish and chip shop challenge

Drive, stop at F&C shop, eat, fill up, drive, see some nice scenary, drive, eat, fill up, go home. If you don't make it, RAC it home.
Re: lpg removal help
Posted: Sun Dec 07, 2008 8:00 pm
by johnna
A Proper Alt fuel thread!!! Whiskey and Parafin next...
Strictly speaking, used chip fat needs de-moisturising as well as straining. Removing the water is essential for any sort of prolonged use.
Which cars are you considering?
Old Mercs are best. Get one with a pump like this:
Pre HDI XUD Pugs and Citroens are second best. Perhaps a 405 or 406 td estate?
I'd say if you were going to go the pug route, change the fuel filter ever other tank. Three quid trade!
Older VAG diesels come third.
You'd be on your own!
A final point. Not all bosch pumps have seals fitted that cope with svo/wvo in any sort of mix. The 325tds is a case in point.
HTH.
Gimme a shout when your thoughts narrow in a bit.
Re: lpg removal help
Posted: Sun Dec 07, 2008 8:02 pm
by johnna
Jon_Bmw wrote:
Depending on the tank age, and from your naff photos

i'd say about £150-350.
I'm no David Bailey...
I'll send you a PM, how do I tell the age of the tank?
The kit came from a jeep cherokee, so should be okay for a 325?
Re: lpg removal help
Posted: Mon Dec 08, 2008 12:47 pm
by johnlouis
that kit is fine for a 325, you wont actually need the AEB160 which is an injector emulator. You will need a switch for the AEB175 / leonardo. The switch contains a PIC Microprocessor communicating to the leonardo over a serial link (spi at a guess) hence cant easily be bodged unfortuantly...
You will need a mixer plate for the AFM and some piping / fittings...
how much did that lot set you back?
Re: lpg removal help
Posted: Mon Dec 08, 2008 1:00 pm
by Jon_Bmw
Pitance!!
You don't want to know

Re: lpg removal help
Posted: Mon Dec 08, 2008 2:32 pm
by Brianmoooore
johnna wrote:how do I tell the age of the tank?
It should be stamped on it. If it's a Stako tank (most are), then there should be a two digit month stamp and a two digit year stamp at the bottom of the ID plate.
The colour will also be a clue if it's a Stako. They were originally green, but changed to black somewhere around 2001.
Re: lpg removal help
Posted: Mon Dec 08, 2008 7:17 pm
by johnna
Cheers guys, will post more details as I get them.
Posted: Mon Dec 08, 2008 8:08 pm
by StuBeeDoo
John, buddy, between the two of us, we can sort this for you.
Just need a decision on what car it's going in. Did the E30 go??
Re:
Posted: Mon Dec 08, 2008 8:20 pm
by johnna
Still got the e30, but no space for it. So still effectively for sale. Oh and zetecs hate lpg...
...but I'd welcome working with you on it!
I've a mixer plate too, but it is a bit flaky.
Re:
Posted: Mon Dec 08, 2008 8:38 pm
by StuBeeDoo
johnna wrote:Oh and zetecs hate lpg...
In what respect?? Don't like running on it? Or valve seat issues?
.....And like I said the other evening.... Another bairn on the way is just the excuse you need to get a 325i Touring to put the gas on.
Re:
Posted: Mon Dec 08, 2008 8:54 pm
by johnna
StuBeeDoo wrote:johnna wrote:Oh and zetecs hate lpg...
In what respect?? Don't like running on it? Or valve seat issues?
.....And like I said the other evening.... Another bairn on the way is just the excuse you need to get a 325i Touring to put the gas on.
I've a 406 chipfat turbo lined up to replace the 306.
I can only have one project car...
The zetec issue is more to do with valve heads going plip off valve stems!
Ford had to produce a special lpg head for the zetecs that run gas.

Re:
Posted: Mon Dec 08, 2008 8:59 pm
by johnna
So: MGB GT Zetec Project, e30 cabby, 306chipfatturbo, 406 chipfatturbo, e30 touring.
Lisa will be pleased! LOL!
Denzils can run lpg... *thinks*
Re:
Posted: Tue Dec 09, 2008 7:11 pm
by johnlouis
johnna wrote:StuBeeDoo wrote:johnna wrote:Oh and zetecs hate lpg...
In what respect?? Don't like running on it? Or valve seat issues?
.....And like I said the other evening.... Another bairn on the way is just the excuse you need to get a 325i Touring to put the gas on.
I've a 406 chipfat turbo lined up to replace the 306.
I can only have one project car...
The zetec issue is more to do with valve heads going plip off valve stems!
Ford had to produce a special lpg head for the zetecs that run gas.

My father had a ford converted LPG focus with the 2l 16v zetec engine in with that head. avoid it at all costs, not becasue of the engine but they used a crappy high pressure system (no vaporiser) that injected liquid lpg into the engine. this required a pump which they had icom mount in the donut tank (yes, in the 45l donut tank, reducing its usable capacity to ~30 l). these pumps burn out after 3000 miles and are not replaceable without 3 arms and a sacrifice to the chinese.
Re:
Posted: Tue Dec 09, 2008 7:43 pm
by StuBeeDoo
johnna wrote:Denzils can run lpg... *thinks*
AFAIK, there isn't a reliable system available. IIRC, there are issues getting accurate dosage as they still require an amount of derv for the combustion process to work on compression ignition.
I'm sure Brian will correct me if this info is wrong.
Re:
Posted: Tue Dec 09, 2008 7:47 pm
by johnna
StuBeeDoo wrote:johnna wrote:Denzils can run lpg... *thinks*
AFAIK, there isn't a reliable system available. IIRC, there are issues getting accurate dosage as they still require an amount of derv for the combustion process to work on compression ignition.
I'm sure Brian will correct me if this info is wrong.
*Stops thinking*
Come over and take a look at it mate.
Re:
Posted: Tue Dec 09, 2008 8:03 pm
by StuBeeDoo
johnna wrote:Come over and take a look at it mate.
I will. Not in any hurry, are you?? I don't have a lot of free daylight hours at the moment. 
I'll lend you Gordon's book/installation manual. 
Re:
Posted: Tue Dec 09, 2008 9:21 pm
by johnna
No hurry in this part of the world!