Conference terri::cars_uk

    I have also heard about this, apparantly, less than 10% of the car fire
    extinguishers on the market ( in Halfords et. ) will put out unleaded
    petrol fires. 
    My source was second hand also though.
    
    Carl.

    
    I'm sure that Derek will correct me on this - but I thought that the
    23 was running unleaded when we had our little fire - the extinguisher
    wasn't one of those 'little things' though. (I would have my doubts
    about the ability of some of those extinguishers to put out anything
    very much, leaded or unleaded.)

I have put out an engine bay fire with a small hand held halon job.

Dave.

    Is this flammability due to the lead-replacement in the fuel?
    
    Chris

    No Chris, its because its lighter now they take the lead out, so th
    flames can reach higher.....:-)
    
    Carl.

    I have heard that unleaded petrol expands in volume (or something
    like that ) during hot weather, and that you actually get less
    petrol for the same price ???
    
    Can anyone comment on this ???

re .7

petrol is stored in tanks deep underground, so the temerature fluctuations 
throughout the year would not be that great 

...art

...and even if petrol did get warm and expand, I don't see why the
lead content should make any difference ;-)

Jc

>>           <<< Note 989.9 by SIEVAX::CORNE "Position Independent" >>>

>>...and even if petrol did get warm and expand, I don't see why the
>>lead content should make any difference ;-)
    
    Dunno, but it's interesting that last summer for the first time ever my
    wife's Citroen Visa's fuel tank overflowed (and we've been in several
    VERY hot summers in Holland). We've generally been putting unleaded in
    for about a year, which includes that period!
    
    Richard

    Does this bring back memories! 15 years ago when unleaded fuel came
    into widespread use in the States, all these old saws were trotted
    out dire predictions for upcoming petro-disasters. Needless to say
    there isn't a shred of truth in them. Speaking for myself, the only
    effect I've noticed is spark(ing) plugs lasting 2 or 3 times longer
    than in the "old days". 
    
    Heat and cold effects? Try -15C to +40C, typical year round variation
    in these parts with nary a problem traced to unleaded fuel.
    
    Wait till you start using methanol/alcohol/MTBE additives in the
    petrol, THEN you'll hear some fanciful stories.
    
    Terry
    

Re: .0

Unleaded petrol has a slightly higher vapour pressure than leaded petrol.
This is a fancy way of saying that it is a tiny bit more volatile than 
leaded and therefore vapourises slightly more readily.

As far as fires are concerned, there is no significant difference.

The only difference anyone might notice is that there is a slightly
increased likelyhood of problems hot starting if you use unleaded fuel,
because vapour locks can develop a little more easily.

Unleaded fuel can about primarily because several lobby groups - notably 
CLEAR (Campaign for LEad-free AiR) - wanted to reduce the levels of lead in
the environment.  Lead is a dangerous cumulative poison that is most
damaging to young children. 

Getting catalytic converters is a separate issue.  From information I have, 
the changes in emission regulations, which will mandate the use of 
catalytic converters, would have happened regardless of whether unleaded 
fuel was currently available.

The fact that unleaded fuel happens to be readily available means that
catalytic converters can be introduced with an impact that is, for all 
parctical purposes, nil. 

jb

    re .12
    With stress on the "slightly,..little and marginal".
    Besides lead-poisoning and non-cathalic convertor usability rules
    out leaded in my book anyway.
    
    Peter