LPG pros and cons
I am looking into an LPG on a 93 300 GES.
I will remove the original exhaust system (cat and all as i think this is legal) and replace with a stainless steel exhaust on the drivers side.
Two under slung tanks will be installed. One on the right and and one at 90 degrees where the exhaust used to cross. This will give me approx 80 litres of lpg and the original fuel tank.
The filler point will be mounted to the left of the tow bar as not to cut any body pannels and keep it discreet.
I have calculated that i will be 'evens' after one year of motoring on fuel cost savings based on about 90% efficiency compared to petrol.
Has anybody experience of this with any advice or warnings?
Is there a 'better' way to do it?
I am currently getting around 16mpg in combined city 70% country 30% driving.
As long as it's done " professionally" with multipoint system they run great, I had a 230 and 280, both on single point and had little issues. But as long as the guys know what there doing !
only one company to use mate, and i mean only 1 !!!
battersea autogas.
pm shakir as he is the lpg expert here.
good luck.
I don't think you can do multi point on this engine. I had single point on a 280ge with 2 underslung tanks but it was not a sucess problems with backfiring into the inlet manifold. You lose 20% or rather can't use 20% of the 80 litres as well. Save your money.
That doesnt sound so great. I have read in previous post that installing an electronic system that prevents back fire is possible? Has anyone done this?
Has anyone done large miles on a convertion with no problems or is prwales experience more common?
KE Jetronic in the ge300 is a mechanical fuel injection system.
fitting an electronic system such as Webers was an occasional if expensive modification to 16v Golf GTI's but that cost £thousands in the early 1990's it would make the conversion to gas very expensive. I don't think that 18/19 mpg is bad for a 2 and a 1/4 ton vehicle
Hi Ian,
my '91 LWB 300GE has single point LPG system with Lambda controlled ECU installed. Cat is still there. Tank is 120 litres, but as mentioned earlied, it can be filled up to 100 litres. 100 litres of LPG gives me 550km range.
Basically, it cheaper to run on LPG.
Backfire was an issue in the beginning, but after changing HV parts like distributor cap, rotor arm and wires, issue dissapeared. My experience confirmes well known fact that LPG system will reaveal lots of issues you will not notice with gasoline - like HV, valve or vacuum leaks.
There is still one classic single point system problem - engine stalling while idle after high revs. Engine will stall if you stop for example in traffic lights. I have'nt heard that this problem has some kind of reliable solution. I guess the stalling problem conceirns more models with automatic transmission as AT gives load to engine while the car is stopped and gear is on.
So, I would suggest to go LPG only if your installer will give 100% guarantee that there will be no stalling with your setup.
hi ian, as mentioned pm shakir. he succesfully runs a 300gel on lpg installed by battersea autogas. this company knows what they are doing. and they have already done this conversion on shakir's G with 99.9% success! [ btw, shakir had extra valves fitted around the inlet which helped prevent backfire issues] lpg is very sensitive to electrical faults . good quality sparks and leads are a must :wink: i used iridium ngk's with big improvements]
i ran my 280 gel on a very old lpg system with very little issues despite the system being fitted in 1990 :shock: !! the G now belongs to another member here,he still runs it on lpg i belive.
my present G300 had an lpg conversion done a year ago....
i ripped the whole lot out :x and still suffer the symptoms because of the bodged up work that was done on it. the injection system was tampered with too !!!!
but this is my bad luck, and other issues too. so dont be put off by this. :(
as mentioned above and good luck.
btw,i agree with what mre1 mentioned too
I forgot that one, idling at 1500 rpm was the only way to stop it stalling at the lights, other drivers look at you in horror.
Ok guys. thank you for the advice.
I am in Northern Ireland so Battersea Autogas is not an option.
I am taking it to a garage recomended by fixwin38 today. I will let them look at it and raise all the concerns mentioned here. I am now a bit concerned by these side effects.
I do not particularly want backfiring, stalling or high idoling as my G attracts enough attention already.
Thanks,
Ian
Ian,dont bother if you ask me !!!!
stay petrol is my final say.
good luck.
Ok guys,
I have spoken to an lpg installer recomended by a friend and he would like to fit a multipoint system with a separate ECU for the lpg injection/timing.
He is 100% confident that the conversion can be done without any of afore mentioned side effects. He took me through each problem and explained why they occur and what is/should be done during installation to prevent them occuring. He has converted over 1000 cars including half a dozen G's. He will replace leads, plugs and distributer cap as part of the installation. His predicted 14mpg on gas so this is also better than i expected.
I think, against all the advice, i am going to go for it....
4 week waiting list though so plenty time for you all to change my mind!
Will keep you posted as to the progress....
Hi Ian,
installing additional ECU sounds bullet proof solution to solve all problems occuring with single point systems, except HV, vacuum or valve leak problems. Meaning, LPG will stay more sensitive to engine trouble and can backfire more easily if some of the mentioned problems is present. Experienced LPG installer will install overpressure release valves to protect intake from damage LPG backfire can cause.
I have a dream to install Megasquirt ECU that can control both, petrol and LPG usin so called dual mapping, This ECU gives also possibility to tune your engine as you like, as someone was interested in "chipping" M103 engine in neighbouring "Petrol" section.
Ian, please share with us the soluttions you heard from the specialist.
I'm particulary interested in the stalling problem solution.
A sequential system on the M103 Mechanical injection engine will be a amazing thing, that is if you can do it.
As Huss mentioned I have the single point system as well with an electronic idle controller, by the way I never needed this controller on my 280. I have back fire valves installed on the intake body. My observations after running 2x Gs on lpg are as follows.
1.BAck fire only happens with faulty cylinder heads and faulty electrics, as mentioned before LPG does not tolerate these.
2.Never had a backfire on my 300 GEL, I dont have an ECU,lambda etc either. but simply engine is ver good cond. New K&N,NGK iridiums,new HT leads .Back fires on 280 was resolved after cylinder head was serviced with new valve guides etc.
3. I recommend lpg to anyone with good engines., don't blame LPG afterwards. And of course get yourself a reputable installer
Installing multi point is perfectly doable. Any LPG installer who can’t get their head round it doesn’t understand the systems he’s installing
Which is of course the norm for the majority of them :)
Doable in theory, like Man can go to Jupiter!
I like to see it done cost effectively and efficiently
russ, any installer can get round fitting an lpg system.....
and thats why ruby almost never made it back from ireland due to a condemned installation, faulty distributor cap, and the G300 being fitted with 280GEL sparks,,,,,,,,,,,,,
lpg is a very sensitive to more faults than petrol. must be trusted be only a reputable installer.
anyone can have a certificate made up and put on the wall :?
There is a german guy,forget his name , Oskar may be, he is in P3 form and he has done a EFI conversion on his 280 G, I really liked that, even better with a sequential system
Guys,
sorry to disapoint but the system is a multipoint single phase injection system not a sequential system.
Just waiting on conformation of cost...
Ian
Guys,
sorry to disapoint but the system is a multipoint single phase injection system not a sequential system.
Just waiting on conformation of cost...
Ian
There’s no need to be disappointed that’s how the petrol injection system works on it :)
In reality you’ve probably got a more advanced system compared to the KE Jetronic. Sequential is no big deal and would be such a minor improvement (if any) If you really insist on sequential as I said previously it’s perfectly doable as long as you can find someone who actually understands engine management systems. Rather than a so called “qualified†LPG installer
I am not disapointed as i only ever mentioned multipoint not sequential...
I think others were rather excited about a sequential system, as would i. Its only engineering so it must be possible, but, like a trip to jupiter, it would be possible, some day, just not economically viable at the moment.
Hi
just bought a petrol g 1991 from the gwoa site and talking to Battersea Autogas
and they seem to know about and have answers for the problems cited here
they say to install a manual rather than electronic mixture unit so that high speed mix and idling can then be adjusted
biggest problem seems to be sourcing a tank to go under the car rather than inside
any thoughts ?
tiny
you can replace your petrol tank and have 25 lt petrol with 70 litre lpg .
very difficult for underneath unlike 460.
Tiny,
I am weighing up whether to loose the exhaust and replace with a 1050x200 and 300x600 tanks underneath and re-route the exhaust to exit under the driverside arch. This gives 70l lpg and original fuel tank.
Or, replace the original tank with the one shakir suggests but have limited fuel reserves for the rare long trip away from lpg. (would need a couple of gerry cans in the boot.)
I have been informed that de-cat with a new exhaust and K&N would also increase performance and efficiency. It will be keeping the noise under control that will be the problem.
The LPG installer i am using has successfully fitted the multi point system to a G300 before without any issues. An engine is an engine is his opinion and its just installing the correct system for the engine. In this instance he replaced the fuel tank.
Thanks for the advice
I think for me the reduced petrol tank option that shakir suggests will be the sensible one
I cant think of when i will be very far from lpg
do you know where to get this type of tank ?
tiny
I have a Multi-point LPG system on my 463. Stalling only occurs (with mine)if you are start/stopping before the engine is warm. I over ride the switch over untill I'm confident!! The savings make this slight iritation livable with.
Doable in theory, like Man can go to Jupiter!
I like to see it done cost effectively and efficiently
Wow I didn’t realise that the only things stopping us from getting to Jupiter were a £20 CPS and a £40 TPS
I’ll inform NASA immediately, I’m sure they’ll be so grateful :roll: :roll:
Hi Ian, great post as i'm new to owning a G mine is a lwb 300GEL Auto and i've been in touch with Battersea Autogas.
My concerns are the obvious, back firing, stalling etc but i'm going to take to them to look at before i take the next step. Will probably be in late January so by then you will already have weighed up all the pros & cons so would appreciate hearing your final decision along with how your fitter plans to eliminate all the problems. Rgds Leo
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Thanks guys.
anyone had any long term issues?