Ford Falcon. Manual - part 182

303-04c-16 

Single Fuel LPG 

303-04c-16

DESCRIPTION AND OPERATION (Continued)

Closed Loop Operation

Vehicle Backfire Information

During closed loop operation the stepper motor is

In the event of backfire, stop and inspect the vehicle

driven open and closed. The HEGO (Heated Exhaust for damage in the form of cracked or split intake

Gas Oxygen) sensor detects rich or lean air fuel

components, dislodged components such as air

ratios. While the HEGO is reading a rich signal, the

cleaner upper or manifold nipple caps, etc. Note that

motor ramps closed and the step position increases.

in extreme cases, backfire can damage the PCV valve

When lean, the motor ramps open and the step

or MAP sensor rendering the vehicle undriveable.

position decreases.

Backfires are caused by poor ignition system

condition or an over-lean air/fuel ratio.

Starting

Engine Coolant Hoses

During engine start, the prime solenoid pulses open

and delivers fuel for a few hundred milliseconds only.

Coolant hoses are connected to the heat exchanger in

The LPG lock-off solenoids are opened as the engine the converter to provide heat, which is required for the

starts to turn and the stepper motor is reset. The

LPG evaporation process.

prime solenoid operation (on time) is dependant on

the engine temperature and the time since the ignition

was previously turned off.

Adaptive Learn Strategy

The PCM control strategy includes an adaptive learn

capability. The system automatically adjusts for

vehicle, environmental, and fuel differences as the car

ages. The adaptive learn system can be reset by

disconnecting the power to the PCM for a few

minutes. This is recommended after servicing the

LPG converter, engine or changing the air filter.

Positive Crankcase Ventilation System

The Crankcase ventilation system is re-routed to the

inlet manifold near the throttle body to ensure even

Item

Description

air/fuel ratio and therefore maintain a smooth idle.

1

Hose from LPG converter to heater

Vapour Hose

2

Quick connector on hose

This unique vapour hose carries the LPG vapour from

3

Hose from engine to LPG converter

the converter to the gas/air mixer.

Engine Servicing Requirements

Gas / Air Mixer

There are no special running-in requirements for this

The function of the gas/air mixer is two-fold:

vehicle. Please refer to the standard running-in

Convert intake airflow into a vacuum signal that is requirements in the Owners Manual.

detected at the converter.

Engine Oil

Thoroughly mix air and fuel together.

The 15W-40 oil specification is recommended.
The combustion products of LPG does not blacken

but tends to acidify the engine oil more than petrol

does. This problem may be exaggerated when oil

change intervals are extended because the oil

appears clean to the owner.

Spark Plugs

Vehicles operating continuously on LPG require a

colder range spark plug than vehicles operating on

petrol.
The recommended spark plugs for LPG are:

Specification: DENSO K20SR11
Gap: 1.1mm

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303-04c-17 

Single Fuel LPG 

303-04c-17

DESCRIPTION AND OPERATION (Continued)

“Repair” means any repair to the vehicle which

Coolant

involves opening the high pressure gas lines to the

The normal service schedule for the cooling system

atmosphere.

should be adhered to. For optimum cooling system

NOTE: LPG fuel tanks must be removed from the

performance of vehicles running on LPG, the

vehicle and be inspected and pressure tested by an

recommended coolant specification is:

authorised tank test centre every 10 years. A plate

Motorcraft Rl-32/33 Anti-corrosion/Anti-freeze

with the original test date and other information is

(33% MIN) and water. This specification provides

attached to the tank. Removal of the tank should only

frost protection to a minimum temperature of

be performed by a registered operator.

-16

°C and should be replaced every 3

NOTE: Running the vehicle on LPG places a greater

years/100,000 km (whichever comes first).

demand on the ignition system (as compared to

It is paramount to cooling system efficiency that this is

petrol) -Accordingly the ignition system must be

the only coolant used. With the addition of extra

maintained in excellent condition. e.g. Replace spark

components into the cooling system (the LPG

plugs at intervals indicated below, without failure.

Converter), it is imperative that the replacement

schedule be strictly adhered to.

In addition to the normal vehicle maintenance

schedule as set out in the Vehicle Owners Manual the

Should the cooling system be dirty, it is necessary to

following minimum maintenance schedule should be

flush out the converter coolant passages in addition to

followed for an LPG equipped vehicle.

the engine cooling system.

Some states require the inspection of the LPG system

Scheduled Maintenance

annually coincident with the registration inspection.

All LPG installations must comply with standard

Where this is not a requirement it is recommended

AS/NZS 1425-1999 and most states require that any

that an annual inspection be performed by an

person engaged in the installation and/or repair of

Authorised Ford Dealer or a registered LPG repairer

LPG vehicles must be registered.

in accordance with the requirements of standard

AS/NZS 1425-1999.

Minimum LPG Maintenance Schedule

Maintenance Interval (kmx1000)

Items

15

30

45

60

75

90

105

120

High Pressure Leak Check:

Converter and lock offs

I

I

I

I

I

I

I

All service line connections

I

I

I

I

I

I

I

I

Filler  valves

I

I

I

I

I

I

I

I

LPG Tank connections

I

I

I

I

I

I

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I

All mounting points for tightness

I

I

Filter/Lock Off - Inspect Filter

F

F

Auto fill limiter operation

I

I

Air Filter Element

I

R

I*

R

I

R

I

R

Spark Plugs

R

Diagnostic Checks

N

N

N

N

N

N

N

N

Drain Second Stage Bodies

D

D

D

D

D

D

D

D

Inspect Idle Jet

I

I

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I

I. Inspection of condition and testing of systems

Replace every 3 years/100,000km.

operation.

When coolant is due for replacement per standard

I*. Clean, replace as required.

service schedule, flush out original coolant and

refill system with R1-32/33

R. Replace.

Anti-corrosion/Anti-freeze (33% MIN) and water.

F. Filter/Lock - off - inspect filter replace as

NOTE: In severe/unusual (dusty/sandy) conditions the

necessary (high pressure leak check when

air cleaner element should be checked, cleaned and

replaced)

replaced more frequently to allow correct operation of

D. Remove plugs and drain converter body

the vehicle.

N. Diagnostics check to be carried out

NOTE: By Australian law tanks must be inspected

NOTE: Engine Coolant must be maintained as

every 10 years by an authorised LPG tank tester.

follows:

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303-04c-18 

Single Fuel LPG 

303-04c-18

DESCRIPTION AND OPERATION (Continued)

NOTE: The total LPG system must be periodically

filter and O-Rings. Refit/replace ensuring the filter is

inspected in accordance with standard AS/NZS

not crimped by the bowl.

1425-1999.

Converter Body

LPG Service Procedures

Drain Second Stage Converter Bodies

LPG number plate decals

This must only be carried out by registered

technicians.

Every time the vehicle is in for service or repair of any

kind, ensure that the red LPG decals are fixed to the

Close the service valve.

front and rear registration plates on metal plates (in

Run the engine until it stalls.

the centre), in the diamond orientation.

Try to re-start engine several times.

NOTE: 1 decal front and rear for sedan and wagon.

Prior to opening the high pressure system to

2 decals front and rear for ute.

atmosphere, the battery negative lead must be

removed and carefully isolated.

Auto Fill Limiter (AFL)
Every 45,000 km it is necessary to test the operation

of the AFL. The tank must be empty to accurately

check the operation of the AFL and owners should be

encouraged to present the vehicle for service with the

tank nearly empty. Instructions to that effect appear in

the owners manual. The remaining LPG in the tank

will need to be decanted.

LPG Filter Service

The filter which is integral with converter requires

inspection and replacement (if necessary) after the

initial 15,000 km of travel and at 75,000 km intervals

thereafter. Always replace ‘O’ rings when replacing

filter.

Item

Description

1

Inlet Filter Bowl

2

Plugs - to drain converter body

Despite the filter prior to the converter, sludge will

gradually accumulate in the converter body and must

be drained at least every 15,000 km to ensure correct

converter operation.
Ideally this should be performed at the same time as

the filter in the filter lock off is replaced and the

converter is devoid of gas.
There are two hex headed drain plugs located at the

base of the converter. Copper washers are installed

between the drain plug heads and the converter body

to ensure sealing of the chambers.

Item

Description

To drain the converter, remove the plugs and allow

1

Inlet Filter Bowl

the sludge to escape – when replacing the plugs

install new copper washers. Conduct a leak test after

2

Plugs - to drain converter body

replacing the plugs. This draining process must be

conducted while the converter/engine is at running

LPG Filter Service Procedure

temperature.

This must only be carried out by registered

technicians.

Idle Jet

Close the service valve.

Clean idle jet every 15,000 km as indicated in the

service schedule. The head of idle jet is a 4 mm

Run the engine until it stalls.

thread (Refer to Converter of Disassembly and

Try to restart engine several times.

Assembly in this section for Tool no. 303-689).

Prior to opening the high pressure system to

atmosphere, the battery negatlve lead must be

removed and carefully isolated. Remove the bowl,

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303-04c-19 

Single Fuel LPG 

303-04c-19

DESCRIPTION AND OPERATION (Continued)

When a leak free condition has been confirmed,

Leak Testing

heating, welding or flame cutting can be carried

High Pressure Leak Testing

out as long as it is no closer than one metre to a

fuel container. The service valve must be closed

A high pressure leak check of the LPG system must

when a vehicle is to be left overnight in the

be carried out at 15,000 kilometre intervals. The

workshop or when stored for any period of time.

standard AS/NZS 1425-1999 requires that this be

carried out at least annually. In most cases this would

Tank Testing

fall in line with one of the 15,000 km service intervals.

An important requirement of the AS/NZS 1425-1999 is

Leak Testing Equipment

the testing and inspection of the LPG fuel tank. Every

ten years, the tank must be removed from the vehicle

The most common method of leak detection is to use

and tested by an Authorised Container Test Station.

a foam test solution. It should be a proprietary leak

Once testing is completed and passed, the tank is

test solution, specifically formulated for this purpose,

stamped with the test date and is ready for another

eg. must not cause corrosion of steel lines etc.

ten years service.

Electronic combustible gas detectors are also

regularly used by many Technicians.

Exhaust Relocation

Refer to the operating instructions supplied with either To provide the extra space required for the gas tanks,

method to ensure accuracy and safety when leak

the exhaust route has been changed and the muffler

testing.

pattern modified. This arrangement however, uses

similar exhaust mounting locations as on the standard

Leak Testing Procedure

BA Falcon.

The fuel system must contain sufficient LPG liquid to

ensure a minimum vapour pressure to 450 kPa,

otherwise a leak check will not be valid.

Begin by testing:

all the tank and filler fittings.
service line joints.

Where possible run or crank the engine to ensure

all components are supplied with liquid LPG.
Test all Filter/Lock Off and Converter connections

and joints.

A large leak can actually blow away the foam solution

and not produce any bubbles, this must be carefully

monitored. Remember since LPG is heavier than air,

test thoroughly below all fittings and components.
Where a leak is indicated, remake the joint, using a

suitable sealing compound. The sealing compound

used must be specifically suitable for LPG

applications.

 CAUTION: Leaking joints with parallel

threads and seats are uncommon. If this type of

joint leaks, check for correct torque. If the leak

persists after re-torquing, the joint must be

replaced. Thread sealing compounds should not

be used to seal these types of joints.

Welding and Heating

The Australian Standard has two requirements

regarding welding and heating on or near an LPG

vehicle.

Until an LPG vehicle has been tested and

confirmed leak free, a Zone 1 hazardous area

exists up to 3 metres from the perimeter of the

vehicle. No welding, heating or flame cutting may

be carried out in this area.

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