lpg starting issues

[bad_religion_au]

got a 76 Fj40 on dual fuel, and like it states above ^ it has difficulty starting in certain conditions, on gas or petrol, but usually on gas.

and if anyone has suggestions of what causes it, any ideas how to fix it?

it won't start sometimes after being driven to normal operating temperature, usually on hot days. and parking in a big open car park (ie outside a shopping complex) on hot days usually makes it almost impossible to start.

usually a squirt of petrol will turn her over, then i gotta quickly do back up the air intake, with gas lines, then flick it across to lpg as it starts to sputter and die from running out of petrol

[pcman]

i find if it dont start to prime the lpg then flick the switch to the middle so no fuel is coming and turn it over it will fire after a few turns then flick the gas back on and give it some accelerator
works every time for me but maby mines just special lol

[V8Patrol]

it won't start sometimes after being driven to normal operating temperature, usually on hot days. and parking in a big open car park (ie outside a shopping complex) on hot days usually makes it almost impossible to start.

Easy fix .............................. stop wheelin K Mart car parks !





Its either to lean or to rich in the mix at hot startup......
is there an LPG primer fitted ( for cold starting usually ) ?, if there is try using it next time, this will add a larger volume of LPG and it should start if its running too lean.
If its to rich in the mix then try switching the LPG OFF 1/2 a second after you initilise cranking, this will limit the amount of LPG entering the engine.

Usually its a poor tune problem that causes poor starting, I assume you have done the usuall checks like plugs/leads/points/condensor/coil/timeing etc ....
I'd also do a "voltage drop" check while cranking the motor over, a voltage drop at the coil will leave you with weak spark and therefore poor starting, are the LPG lockout valves staying open during cranking?, again a voltage drop may cause them to close leaving the engine with no fuel at all. Is the starter motor drawing more power than it should ?, an old/worn starter will draw a heap more voltage in order to spin over thus leaving little voltage for coil/lockoutvalves/etc.... to work @ 100%

have a nice w/end

Kingy

[vraamm]

ive experienced a similar problem with my dual fuel cruiser
wouldnt start on both fuels when realy hot, increasing difficulty starting on LPG at all times. As V8Patrol said [Is the starter motor drawing more power than it should ?, an old/worn starter will draw a heap more voltage in order to spin over thus leaving little voltage for oil/lockoutvalves/etc.... to work @ 100%]. This was my problem, recon of the starter sorted it out as well as changing some wiring to the dizzy. If your starter cranks over a lot slower than someone elses does this may be your problem.[/quote]

[Begbie]

Look inb the carb and make sure the accelerator pump is working, sounds like it might wanna be replaced. (cheap and easy)

[bad_religion_au]

starter is new, spins fine. it's really bugging me that it only seems to happen on hot days.

primer is fitted, and even using that, nothing happens. i'll try cranking it with it in the center position next time (for 1/2 sec or whatever) it happens.

thought it might be weak spark, because it did have a weak spark when starting with the old battery, but the new battery seems to provide plenty of spark.

ummm as for the rest, still checking