LPG

[Martinaston]

Assuming that one day all garage forecourts will have an LPG pump, what reasons are there to stop you useing the original petrol tank as the LPG tank rather than a second one in the boot ?
The only one i can think of is if it is pressurised.
But then i know very little about LPG.
Any ideas ?

[Simon13]

Any ideas ?

No

[Martinaston]

Well we all new that about you anyway

[TOURINGDADDY]

is also made of stronger material and is crush resistant u also need a petrol tank as u still have to start the car on petrol

[Martinaston]

I've seen them made of kevlar and resin so they don't rupture but i thought that was because they were normally mounted in the passenger compartment.

So is it not possible to start the engine on LPG ?

[Simon13]

So is it not possible to start the engine on LPG ?

No

[TOURINGDADDY]

not in server cold temp has a safty temp switch also is not as combustable as pety

[Martinaston]

Does the temp switch stop you using the LPG when it's too hot or too cold ?

[TOURINGDADDY]

only when the water that cools the vaparisor is frozen will the gas not work!

[Martinaston]

A bit of antifreeze should cure that ? Or does it work at too hot a temp ?

As for the tank, the gas is not kept at a higher pressure though is it ?

[TOURINGDADDY]

the gas is kept at very high pressure not sure what will tyr and find out
but dont matter how hot it gets it will still work and u plumb the vaperisor in the cars coolent system

[Martinaston]

So if i wanted to use the petrol tank for LPG i guess i would have to get a custom one built to take the pressure.
Looks like another nail in the E30 coffin

[TOURINGDADDY]

Looks like another nail in the E30 coffin
WHY

[Widge]

Cars can start and run on LPG in any conditions. Just look at the 2002 LPG powered racer on Jaymec's website. How ever the nomal petrol engine is not high enough compression to start on LPG - LPG only engines are rebuilt with higher comps and specific inlet stuff etc which then makes the engine unsuitable for petrol. This is why when switching to LPG on a normal petrol engine there is a loss of power, typically 10% on a single point injection system. So converted cars usually start on petrol and automatically switch to LPG after a min or so. So you'll need a pressurised tank to run the E30 on LPG.

[m1key]

although i have heard that LPG is about the equivelent of 110 octane fuel.

you just need an engine that is designed correctly to run it.

i have had my LPG installed for about 4 weeks now, i start on LPG and have no problems.

[Martinaston]

m1key how much did it all cost and what tank do you have ?

[Brianmoooore]

You can't use the petrol tank for LPG because LPG is stored at 100 PSI+ (very dependant on temperarure), and if you remove the petrol tank, the available space is not very suitable for LPG tanks, because pressure vessels need to be spherical or variations of that, and 9" clearance is required between any part of the LPG system and the exhaust.
I looked into removing half the petrol tank once, and found I could only get about 9l of LPG in the space released.
There is no problem whatsoever in starting a car on LPG from cold. The problem arises shortly afterwards. LPG needs a lot of energy to change it from liquid to gas, and this energy is obtained from the engine coolant.
In very cold weather, the amount of heat removed from the coolant may exceed that supplied by the engine just after start up, and result in the coolant in the vapouriser freezing, antifreeze or not. This wll let liquid LPG through to the injectors and can cause injector failure.

There is a big deep well in the boot of your car, which is normally used to cart around a full size extra wheel, that you need on (statistically) average every 90,000 miles. This is an ideal site for an LPG tank.

[m1key]

70 litre tank, and kit cost Ԛ£450.

[Martinaston]

Cheers Brian

I guess you had the same idea, Looks like the exhaust rules it out though

Cheers m1key

Does it all work ok ?
I've heard some real horror storys about badly installed ones (pile of ashes that used to be a car)

[dazleeds]

Damn that was my future plan too
bin the petrol tank for smaller oh well rethink time Daz

[Chaos]

although i have heard that LPG is about the equivelent of 110 octane fuel.

yes but it has a lower calorific value apparently

[Widge]

and result in the coolant in the vapouriser freezing, antifreeze or not. This wll let liquid LPG through to the injectors and can cause injector failure.

That's why they use electronic vaporisers on engines designed to start on LPG.

[Brianmoooore]

although i have heard that LPG is about the equivelent of 110 octane fuel.

yes but it has a lower calorific value apparently

Yes, UK autogas (unlike French GPL), has a calorific value about 20% less than petrol. And the relevance oif this is?

[Brianmoooore]

and result in the coolant in the vapouriser freezing, antifreeze or not. This wll let liquid LPG through to the injectors and can cause injector failure.

That's why they use electronic vaporisers on engines designed to start on LPG.

I thought I was pretty well up to speed on LPG systems, but I've never heard of these. Tell me more, please.

[philglasgow]

although i have heard that LPG is about the equivelent of 110 octane fuel.

you just need an engine that is designed correctly to run it.

i have had my LPG installed for about 4 weeks now, i start on LPG and have no problems.

Hi Mikey

Can you tell me if you fitted it yourself or got an installer, I have a system in a car at present and am looking to get it fitted to my tourer, and looking for viable options .

[Widge]

Soory for the slow reply Brian, I don't think electronic vaporisers are used much purely as they have flammable gas and an electric heating element in them so people don't like it. I only heard of a guy in the states using them as he was converting his pickup to totally LPG with a huge tank.

[m1key]

phill, i did it my self and took it to an auto gas installer who checked it.

was time consuming more than anything.

m