lpg problems - any ideas?

[Ext User(Shakir)]

Hey all...

I have a 351 in a zc fairlane running on duel fuel (IMPCO 300a) snorkel
system.

A while ago it started playing up.

It would drive to work fine then in the arvo it would start fine but then
when I take off and give any throttle it would die in the ass...

A bit like when you get freeze over from lack of water (but it wasnt that).

I decided to try to fix by elimination process and started by replacing the
thermostat (just in case it was a water problem - which it wasnt).
No change... So I went to a friends ford wrecker and he had a converter
axactly the same off a running car so I changed it over and it seemed to fix
the problem for a couple of months!
Even took a trip from melb to sydney and back.
But it as started to intermittently do it again! argh!

Hard to pinpoint or take somewhere because its only sometimes - but same
problem... dstarts and idles fine.. go to take off under any throttle load
and it will die!

Im thinking maybe trying to replace the mixer this time and see if that
helps?

Any ideas or help?

I wish it was a newer style system without the snorkel etc but just cant
afford an upgrade at this stage.

Thanks
Shakir

[Ext User(Shakir)]

and its connected to a 4bbl double pumper mech holley ;)

[Ext User(mark jb)]

> Hard to pinpoint or take somewhere because its only sometimes - but same
> problem... dstarts and idles fine.. go to take off under any throttle load
> and it will die!

check your ign leads.

-mark

[Ext User(Shakir)]

ign seems fine - it only happens when throttle is revving... ?



"mark jb" <a@b.c> wrote in message
news:12rgi58na2t51fe@corp.supernews.com...
>> Hard to pinpoint or take somewhere because its only sometimes - but same
>> problem... dstarts and idles fine.. go to take off under any throttle
>> load and it will die!
>
> check your ign leads.
>
> -mark
>

[Ext User(atec)]

Shakir wrote:
> and its connected to a 4bbl double pumper mech holley ;)
>
>
>
So have you cleaned the wax out the converter ?

[Ext User(Noddy)]

"Shakir" <shakir(at)sexbeatrecords.com> wrote in message
news:45b845a4$1@dnews.tpgi.com.au...


> Hard to pinpoint or take somewhere because its only sometimes - but same
> problem... dstarts and idles fine.. go to take off under any throttle load
> and it will die!
>
> Im thinking maybe trying to replace the mixer this time and see if that
> helps?
>
> Any ideas or help?

The very first thing to check on a problematic gas burner is the ignition
system, as it needs to be in 110% condition for a good running engine.

If the ignition system is okay, then you need to find out why the gas
suddenly stops finding it's way into the engine, and there can be a number
of reasons for that such as faulty lock off valves, converter freezing,
fucked converter diaphragm or the mixer itself could be causing the problem.

If it were mine, the first two places I'd be looking based on your symptoms
would be the lock off, or checking to see that the converter is hot next
time it falls over.

--
Regards,
Noddy.

[Ext User(Shakir)]

errrr .no.
Its a learning curve with lpg for me... i have no clue LOL

?



"atec" <"atec77 "@hotmail.com> wrote in message
news:45b84de5$0$11207$61c65585@uv-55king-reader-01.melbourne.pipenetworks.com.au...
> Shakir wrote:
>> and its connected to a 4bbl double pumper mech holley ;)
>>
>>
>>
> So have you cleaned the wax out the converter ?

[Ext User(Shakir)]

thanks noddy - but yeah I have checked converter for freez-over and its
always hot as the radiator so its definitely getting water to it no problem.

Id say the ignition leads etc are pretty crappy and probably original 1970
zc fairlane ones at that but I would have thought if it was electrical then
it wouldnt idle or start as well as the problem under throttle but its only
when throttle is applied that the problem comes (and goes) ...


argh!


"Noddy" <dg4163@(nospam)dodo.com.au> wrote in message
news:45b8687d@news.comindico.com.au...
>
> "Shakir" <shakir(at)sexbeatrecords.com> wrote in message
> news:45b845a4$1@dnews.tpgi.com.au...
>
>
>> Hard to pinpoint or take somewhere because its only sometimes - but same
>> problem... dstarts and idles fine.. go to take off under any throttle
>> load and it will die!
>>
>> Im thinking maybe trying to replace the mixer this time and see if that
>> helps?
>>
>> Any ideas or help?
>
> The very first thing to check on a problematic gas burner is the ignition
> system, as it needs to be in 110% condition for a good running engine.
>
> If the ignition system is okay, then you need to find out why the gas
> suddenly stops finding it's way into the engine, and there can be a number
> of reasons for that such as faulty lock off valves, converter freezing,
> fucked converter diaphragm or the mixer itself could be causing the
> problem.
>
> If it were mine, the first two places I'd be looking based on your
> symptoms would be the lock off, or checking to see that the converter is
> hot next time it falls over.
>
> --
> Regards,
> Noddy.
>

[Ext User(Andy)]

Shakir wrote:
> thanks noddy - but yeah I have checked converter for freez-over and its
> always hot as the radiator so its definitely getting water to it no problem.
>
> Id say the ignition leads etc are pretty crappy and probably original 1970
> zc fairlane ones at that but I would have thought if it was electrical then
> it wouldnt idle or start as well as the problem under throttle but its only
> when throttle is applied that the problem comes (and goes) ...


Replace your ignition leads. Seriously.

http://www.magnecor.com.au/


> argh!

Indeed.


Cheers,

Andy. (t'other Andy.)

[Ext User(atec)]

Shakir wrote:
> errrr .no.
> Its a learning curve with lpg for me... i have no clue LOL
>
> ?
>
>
>
> "atec" <"atec77 "@hotmail.com> wrote in message
> news:45b84de5$0$11207$61c65585@uv-55king-reader-01.melbourne.pipenetworks.com.au...
>> Shakir wrote:
>>> and its connected to a 4bbl double pumper mech holley ;)
>>>
>>>
>>>
>> So have you cleaned the wax out the converter ?
>
>
AH ok , well IF the ignition system is sound then you need to be sure
the converter is warm and that it's not full of rubbish and if the gas
is getting where it should .

[Ext User(Noddy)]

"Shakir" <shakir(at)sexbeatrecords.com> wrote in message
news:45b86b1b$2@dnews.tpgi.com.au...

> thanks noddy - but yeah I have checked converter for freez-over and its
> always hot as the radiator so its definitely getting water to it no
> problem.

Sounds like it's not that then.

> Id say the ignition leads etc are pretty crappy and probably original 1970
> zc fairlane ones at that but I would have thought if it was electrical
> then it wouldnt idle or start as well as the problem under throttle but
> its only when throttle is applied that the problem comes (and goes) ...

Electrical problems show up worst under load (like almost anything else), so
I'd be addressing those items as "things that needed to be done anyway".

From what you've described it sounds like it's running out of fuel in a
hurry (although it's next to impossible to be sure without seeing it happen
personally), and I'd still be looking at the fuel lock off (and/or it's
electrical connections or filter), or the converter diaphragm.

If the diaphragm isn't up to scratch it won't perform on the vacuum signal
it's supposed to (which even though is generally very low it doesn't take
much swelling of the diaphragm for it to be a major pain in the arse).
Depending on what converter you have kits are available at reasonable prices
and are easy to fit.

--
Regards,
Noddy.

[Ext User(Noddy)]

"Shakir" <shakir(at)sexbeatrecords.com> wrote in message
news:45b86894$1@dnews.tpgi.com.au...
> errrr .no.
> Its a learning curve with lpg for me... i have no clue LOL

That's where everyone starts, so it's no big deal.

Gas converters have a large rubber diaphragm inside them that controls the
gas flow to the engine, and it's operated by engine vacuum. The vacuum
signal required to make them open & close properly is very low, but the
problem with them is that they become erratic as they age due to them being
attacked by the various chemicals and other contaminants (namely Butane)
that's found in auto lpg.

Ideally, a good gas converter should have it's supply hose located at the
very bottom of the converter so any crap that may otherwise build up and
stuff the diaphragm is sucked straight into the engine and burnt. However,
with that not always being possible with some converters and their
particular installations, it becomes necessary for the converter to be
serviced periodically to keep it in good working order.

Such a "service" on a converter would normally consist of cleaning the built
up crap out of the inside of the thing, and fitting a new diaphragm to
return it to normal working condition. This isn't a difficult task, and can
normally be done by anyone with a reasonable amount of mechanical ability. I
dare say that if you're capable of changing a converter without turning
yourself into the fist person in orbit who *didn't* use a rocket to get
there you're more than capable of doing such a repair.

Because you're running a 300A mixer you should have a "simple" converter
(which basically means all the tuning aspects are controlled by the mixer
rather than the converter which is just there to vaporize the fuel), so
repairing even the worst of these things should be a snap.

As I mentioned before, I'd still look at the fuel lock off valve, and it's
filter if it has one. The lock off valve is a 12v solenoid controlled brass
valve that lives in the line between the tank and the converter, and they're
normally somewhere in the engine bay near or right on the converter itself.
They're usually wired into the positive side of the ignition coil (normally
through a safety switch that detects rpm) so when you turn the key on the
solenoid is charged, and the gas supply to the converter is opened.

If it has a filter, it'll have a small brass bowl about the size of a golf
ball or so at the bottom of the valve, and inside here will be a tiny paper
element filter that traps the rust, dirt and other crap that finds it's way
into the gas tank and prevents it getting into the converter and ultimately
the engine.

These filters are available from most lpg installation people or car parts
outlets for a few bucks, and it's handy to keep a spare. They're a piece of
piss to change, but you *must* turn the gas supply off at the tank *before*
attempting to do so as the filter is on the "open" side of the valve between
the valve and the tank. Failure to do so will most certainly see you being
the first human on Mars :)

If it were my car I'd look at the electrical first, then the filter if it
has one, *then* the converter.

--
Regards,
Noddy.

[Ext User(Shakir)]

LOL thanks noddy hehe..
Yeah I did actually turn off the gas and check the knock off valve filter
etc and that was clean as a whistle.
I did that 1st before changing the converter a couple of months ago hoping
it was simply a dirty filter but nope :(

any ideas where I can get kits for 300a's ? its the 1&20 model


fanx!
Shakir :)


"Noddy" <dg4163@(nospam)dodo.com.au> wrote in message
news:45b88d54@news.comindico.com.au...
>
> "Shakir" <shakir(at)sexbeatrecords.com> wrote in message
> news:45b86894$1@dnews.tpgi.com.au...
>> errrr .no.
>> Its a learning curve with lpg for me... i have no clue LOL
>
> That's where everyone starts, so it's no big deal.
>
> Gas converters have a large rubber diaphragm inside them that controls the
> gas flow to the engine, and it's operated by engine vacuum. The vacuum
> signal required to make them open & close properly is very low, but the
> problem with them is that they become erratic as they age due to them
> being attacked by the various chemicals and other contaminants (namely
> Butane) that's found in auto lpg.
>
> Ideally, a good gas converter should have it's supply hose located at the
> very bottom of the converter so any crap that may otherwise build up and
> stuff the diaphragm is sucked straight into the engine and burnt. However,
> with that not always being possible with some converters and their
> particular installations, it becomes necessary for the converter to be
> serviced periodically to keep it in good working order.
>
> Such a "service" on a converter would normally consist of cleaning the
> built up crap out of the inside of the thing, and fitting a new diaphragm
> to return it to normal working condition. This isn't a difficult task, and
> can normally be done by anyone with a reasonable amount of mechanical
> ability. I dare say that if you're capable of changing a converter without
> turning yourself into the fist person in orbit who *didn't* use a rocket
> to get there you're more than capable of doing such a repair.
>
> Because you're running a 300A mixer you should have a "simple" converter
> (which basically means all the tuning aspects are controlled by the mixer
> rather than the converter which is just there to vaporize the fuel), so
> repairing even the worst of these things should be a snap.
>
> As I mentioned before, I'd still look at the fuel lock off valve, and it's
> filter if it has one. The lock off valve is a 12v solenoid controlled
> brass valve that lives in the line between the tank and the converter, and
> they're normally somewhere in the engine bay near or right on the
> converter itself. They're usually wired into the positive side of the
> ignition coil (normally through a safety switch that detects rpm) so when
> you turn the key on the solenoid is charged, and the gas supply to the
> converter is opened.
>
> If it has a filter, it'll have a small brass bowl about the size of a golf
> ball or so at the bottom of the valve, and inside here will be a tiny
> paper element filter that traps the rust, dirt and other crap that finds
> it's way into the gas tank and prevents it getting into the converter and
> ultimately the engine.
>
> These filters are available from most lpg installation people or car parts
> outlets for a few bucks, and it's handy to keep a spare. They're a piece
> of piss to change, but you *must* turn the gas supply off at the tank
> *before* attempting to do so as the filter is on the "open" side of the
> valve between the valve and the tank. Failure to do so will most certainly
> see you being the first human on Mars :)
>
> If it were my car I'd look at the electrical first, then the filter if it
> has one, *then* the converter.
>
> --
> Regards,
> Noddy.
>
>
>
>

[Ext User(Noddy)]

"Shakir" <shakir(at)sexbeatrecords.com> wrote in message
news:45b88eed$1@dnews.tpgi.com.au...

> I did that 1st before changing the converter a couple of months ago hoping
> it was simply a dirty filter but nope :(

Bugger.

> any ideas where I can get kits for 300a's ? its the 1&20 model

I'd just try the local lpg fitter in your area. If they don't have them,
they could tell you where to get them.

--
Regards,
Noddy.

[Ext User(Jason James)]

"Shakir" <shakir(at)sexbeatrecords.com> wrote in message
news:45b845a4$1@dnews.tpgi.com.au...
> Hey all...
>
> I have a 351 in a zc fairlane running on duel fuel (IMPCO 300a) snorkel
> system.
>
> A while ago it started playing up.
>
> It would drive to work fine then in the arvo it would start fine but then
> when I take off and give any throttle it would die in the ass...
>
> A bit like when you get freeze over from lack of water (but it wasnt
that).
>
> I decided to try to fix by elimination process and started by replacing
the
> thermostat (just in case it was a water problem - which it wasnt).
> No change... So I went to a friends ford wrecker and he had a converter
> axactly the same off a running car so I changed it over and it seemed to
fix
> the problem for a couple of months!
> Even took a trip from melb to sydney and back.
> But it as started to intermittently do it again! argh!
>
> Hard to pinpoint or take somewhere because its only sometimes - but same
> problem... dstarts and idles fine.. go to take off under any throttle load
> and it will die!
>
> Im thinking maybe trying to replace the mixer this time and see if that
> helps?
>
> Any ideas or help?
>
> I wish it was a newer style system without the snorkel etc but just cant
> afford an upgrade at this stage.

I have a similar car but with a different convertor. Some observations: the
gas gear is reliable, but I had very bad stability problems on gas for the
first few months similar to yours. That after a lot of mucking around by the
installer, turned out to be a damaged EGR carby base gasket. Your Fairlane
may not have this,..but the moral of this story was: anything that may cause
even slight upset of air-fuel mixture atlow engine speeds (idle, off idle)
is a lot more noticeable on gas than petrol. Make sure if you are still
having problems, that there are no airleaks around the base of the carby and
any lines going to the base. If in doubt, a renewal of the carby base
gaskets may well help,...given everything else has failed to find it. Make
sure your brake-booster is holding vacuum for at least 10 minutes after
switch off. If not, let us know. Make sure your vacuum advamce is working.
Make sure there are no perished hoses around the carby base connections.

best o luck- Jason

[Ext User(John McKenzie)]

Shakir wrote:
>
> Hey all...
>
> I have a 351 in a zc fairlane running on duel fuel (IMPCO 300a) snorkel
> system.
>
> A while ago it started playing up.
>
> It would drive to work fine then in the arvo it would start fine but then
> when I take off and give any throttle it would die in the ass...
>
> A bit like when you get freeze over from lack of water (but it wasnt that).
>
> I decided to try to fix by elimination process and started by replacing the
> thermostat (just in case it was a water problem - which it wasnt).
> No change... So I went to a friends ford wrecker and he had a converter
> axactly the same off a running car so I changed it over and it seemed to fix
> the problem for a couple of months!
> Even took a trip from melb to sydney and back.
> But it as started to intermittently do it again! argh!
>
> Hard to pinpoint or take somewhere because its only sometimes - but same
> problem... dstarts and idles fine.. go to take off under any throttle load
> and it will die!
>
> Im thinking maybe trying to replace the mixer this time and see if that
> helps?
>
> Any ideas or help?

The 300a is a piece of shit. before I sound too much like a prick, it's
a piece of shit because it's got a fairly large diameter diaphragm and
the bigger it is the more subject it is to ballooning. What happens then
is that at idle or low rpm, it won't give anywhere near as consistent
amount of gas metering. It can even get to the point that the moving
piston (or air valve or whatever it's referred to as) will stick on it's
seat, so if you go to rev it, it won't lift and then it runs so rich it
dies in the arse.

Taking it apart and cleaning the areas where it slides (it'll make sense
when you look at it) including the rotating plate that is the cable
selection half of the lpg/petrol switching process might help.

In addition to that, by the very nature of how lpg setups meter lpg for
idle and low rpm (basically they aren't as good as a well designed, or
some might argue poorly designed carburettor idle circuit) a case of
borderline ignition output will show up with harder starting/idle and
cold running on lpg, whilst it will still perform flawlessly on petrol
quite often.

As a very general thing, replace leads and coil and dist cap and rotor
every five years or sooner if they are problematic, or if the car does a
lot of kms. I'm not sure when ford went to hei ignition, but I'd
_definitely_ suggest going to the later model dizzy and commensurate
coil if you can. It'll be much happier starting etc on lpg. The only
thing you do different is you don't run the plug gap to the original hei
model plug gap spec. You keep it at the gap recommended by the factory
for the points spec. this is an idiosynchrasy of lpg, and even many
engine management/coil pack ignition cars benefit from a 5thou or so
closer gap when on lpg.

Reeplacing the thermostat on a yearly basis is good insurance. Ignore
any dickheads (including some gasfitters) who suggest running a colder
thermostat. Lpg convertors were by and large designed to run at 190 or
195F coolant temp, and any cooler than that and they just use extra lpg
and kill off potential mileage. Most people don't expect lpg mileage to
be any good and just put up with it. It'd be a likely 10% or better
improvement just going from a 160 to a 190 thermostat. They don't last
forever anyway, so you might as well replace them. Typically engine
longevity is tied to coolant temp to. It might sound arse backwards, but
generally the hotter the engine runs, (short of seizing of course) the
longer it lasts.

> I wish it was a newer style system without the snorkel etc but just cant
> afford an upgrade at this stage.

Try the stuff above and let us know how you go. It should sort it out,
but it might mean you need to do the cleaning of the mixer itself yearly
or so. Use hot soapy water, not solvent based cleaners as they will only
affect the diaphragm even more.

--
John McKenzie

tosspam@aol.com abuse@yahoo.com abuse@hotmail.com abuse@earthlink.com
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[Ext User(John McKenzie)]

Shakir wrote:
>
> any ideas where I can get kits for 300a's ? its the 1&20 model

Whereabouts are you? Most lpg fitters would have them. some are less
keen to sell to the general public. Some are fairly decent. If you
happened to be anywhere near the Tulla Airport, 'lpg conversions' which
is in 5-7 freight drive tullamarine, 9330 3555 are nice enough blokes to
deal with, I haven't there for a while, but Stuart should be able to
help with anything you need if he's still around (I dare say he would
be, his dad started the firm years back, and they've been flat out there
ever since.)


--
John McKenzie

tosspam@aol.com abuse@yahoo.com abuse@hotmail.com abuse@earthlink.com
abuse@aol.com vice.president@whitehouse.gov president@whitehouse.gov
sweep.day@accc.gov.au uce@ftc.gov admin@loopback $LOGIN@localhost
abuse@cia.gov If you've got a blacklist,I want to be on it $USER@$HOST
$LOGNAME@localhost -h1024@localhost root@mailloop.com abuse@msn.com
abuse@asio.gov.au abuse@federalpolice.gov.au fraudinfo@psinet.com
$USER@localhost abuse@sprint.com abuse@fbi.gov abuse@iprimus.com.au

[Ext User(Shakir)]

Thanks to all for your excellent info and replies!
Will endevour to do all suggested and see what happens :)


Shakir

[Ext User(Jason James)]

"Jason James" <home@work.1.0> wrote in message
news:45b910a4$0$3203$c30e37c6@ken-reader.news.telstra.net...
>
>
> I have a similar car but with a different convertor. Some observations:
the
> gas gear is reliable, but I had very bad stability problems on gas for the
> first few months similar to yours. That after a lot of mucking around by
the
> installer, turned out to be a damaged EGR carby base gasket. Your Fairlane
> may not have this,..but the moral of this story was: anything that may
cause
> even slight upset of air-fuel mixture atlow engine speeds (idle, off idle)
> is a lot more noticeable on gas than petrol. Make sure if you are still
> having problems, that there are no airleaks around the base of the carby
and
> any lines going to the base. If in doubt, a renewal of the carby base
> gaskets may well help,...given everything else has failed to find it. Make
> sure your brake-booster is holding vacuum for at least 10 minutes after
> switch off. If not, let us know. Make sure your vacuum advamce is working.
> Make sure there are no perished hoses around the carby base connections.

Just another thing on mine which caused a lot of problems on gas and
effected brake performance at idle in slow moving traffic: the PCV valve was
original and had become intermittant. It lives on the end of a large vacuum
hose, and is plugged into one of your rocker covers (not sure if you have
the Windsor or Cleveland engine). Its main job is to suck gases that
build-up inside the engine and to do this, it is connected to the inlet
manifold. If it is playing up, it can cause poor starting and idle and
stalling problems on gas especially. They can be cleaned, but if its
original a new one costs aroud $15.

Jason