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[Martin_1962]

 Fuel Feed System.

 The essential difference between the fuel feed system for a liquid fuel injection system
and a non-fuel injection engine (carburettor) or a vapour injection engine is the absence
 of a vaporiser.


 Fuel Feed Pump.
 A pump is required to raise the fuel pressure, which will otherwise be at the vapour
 pressure of the liquid in the fuel tank, to a sufficiently high pressure to ensure it
 remains liquid throughout the fuel system allowing for heat gain in the vicinity of the
engine when running and to avoid hot restart problems due to heat soak after shut down,
or at switch over, if it is a bi-fuel system.
 Pump external to the fuel tank.      Feed from the bottom of the tank or from the top via
 a dip tube. In either case the suction line should be gererous in diameter and as shot as
 possible to avoid pump damage from cavitation.

 Submerged pump in the fuel tank.    This avoids the likelihood of cavitation.

 Pressure Control.
To provide a constant feed pressure to the injectors, a pressure controller is normally
provided. This may form part of the management system of the engine or the
conversion equipment.

 
 REQUIREMENTS FOR BUSES AND MINIBUSES

  Regulations.
 The Road Vehicle (Construction and Use) Regulations 1986 call for special requirements over and above those elsewhere in this Code relating to fuel systems for buses and minibuses. Some buses and minibuses may be classified as Passenger Service Vehicle (Conditions of  Fitness, Equipment, Use and Certification) Regulations 1981, generally referred to as C.O.I.F., being the conditions of Initial Fitness. These also apply to some vehicles which are not buses or minibuses as defined but carry passengers who pay individually.

 PSVs are required to be inspected by the Department of Transport, Vehicle Inspectorate,
Swansea, before entry into service.

 This section applies to buses and minibuses, but if they are to operate as PSVs the legal requirements for the fuel system should be discussed with the Vehicle Inspectorate
 Department of Transport at an early stage.

 Where the following requirements are taken from the Passenger Service Vehicle (Conditions of Fitness, Equipment, Use and Certification) Regulation, they are indentified by (C O I F ).
 
Fuel Tanks.
 The LPG fuel tanks, pipework arrangements, associated fittings and valves shall be located to comply with previous location guidelines and the following special requirements:-

 Fuel tanks shall not be situated within 600mm of the entrance/exit on a vehicle with more than 12 passenger seats nor within 300mm of any entrance/exit on a vehicle with 12 passenger seats or less (C O I F 13).
Fuel tanks may be externally mountes or may be within the passenger compartment only if suitably enclosed and protected . (C O I F 13).
 Fuel tanks mounted beneath a vehicle shall:-
 Preferably be at least 500mm inboard of the sides of the vehicle or on the inside of the
chassis longitudinal frame members where applicable. If this location is not technically
 possible, it is permissable to locate LPG fuel tanks outboard of this, but within the width
 of the vehicle, in which case, suitable caging or structural fixtures shall be provided
to protect them  and their associated fittings from severe side impacts.
 Have adequate ground clearance in line with the vehicle manufacturers recommendations forladen and unladen use.

 
Fuel tanks for vehicles over 5 tonnes Gross Vehicle Weight shall be situated between the
 front and rear axles.

 Fuel tanks shall be situated as far as practicable from the exhaust system. If the clearance
 is less than 250mm adequate shielding against heat radiation shall be provided.

 Roof-mounted fuel tanks shall comply with guidelines already set out. PSVs need to be
 assessed for the legal requirements for stability. (C O I F 6).

 Tilt/inertia Cut-off switches (applies to all buses).

 A vehicle tilt switch and an inertia switch are required both of which shall cause the electric solenoid valves at the outlet of each tank to close.
The tilt switch shall cause the fuel tank valves to close when the vehicle body angle of
tilt to the vertical is greater than 35 degrees for single deck vehicles, or 28 degrees
for double deck vehicles.

 The inertia switch shall cause the fuel tank valves to close in the event of deceleration
 of the vehicle exceeding 5g. The valves shall remain closed after actuation until the
inertia switch is manually reset.

  Fuel Tank Fill Connection.

 The filling point shall be accessible only from the outside of the vehicle (C O I F 13).
For vehicles with less  than 12 passenger seats, the filling point shall not be at the rear
 of the vehicle. (C O I F 13).
 The fuel tank fill connection shall not be within 300mm of any door or other aperature
 into the vehicle interior (C O I F 13).

 The fuel tank fill connection shall not be located within 500mm of the exhaust outlet.

[sassanach]

how many times did you try it?

[Martin_1962]

  Pressure Relief Valve (PRV) Discharge.

 
The discharge shall be directed downwards so as not to impinge on any part of the vehicle and shall be arranged as far as practicable so as to be clear at all times of the vehicle flooring, tyres, wheel arches, fuel tanks, manifolds and exhaust systems.

 LPG Fuel System Relative to Vehicle Interior Apertures.
 The design, location and installation of the LPG fuel system shall be arranged so that
no leakage from the LPG fuel system shall enter the vehicle interior.

 The PRV discharge shall be directed as far away as is necessary from all openings and
 apertures into the vehicle to avoid leakage into the vehicle interior and so as not to
interfere with people exiting from the vehicle in an emergency when the PRV may be venting and so that no fuel overflowing or leaking can accumulate on any woodwork or other part of the body such that it might be  readily ignited.(C O I F 13 (2) ).


 Fuel feed Pipe.

 The LPG feed pipework shall comply with guidelines already set out and shall not pass through the passenger or driver compartments.

  Manual External Fuel Cut-off.

 A device shall be provided  by means of which the supply of fuel to the engine can be
readily cut off. The means to cut off shall at all times be readily accessible from outside
 the vehicle and shall be operated by hand. The location of the means of cut off shall be
clearly marked on the outside of the vehicle, and indication of the function and means of
 operation to the cut off shall be provided nearby. The “off” position shall be clearly
indicated.(C O I F 13 (1) d).
 The fuel cut off may be provided by any combination of the following:-
A manual device, accessible from outside the vehicle, which directly or indirectly closes
 a valve in the LPG supply and simultaneously for a bi-fuelled vehicle, cuts off the
 petrol feed.

 
Closing of the externally operated battery isolation switch (where provided), which in turn,
results 8in the closure of the valves.

 Closing of an LPG fuel pipe manual valve located near to and upstream of the vaporiser.

 

 
 Fuel Gauges.
A dashboard fuel gauge shall be provided. For multiple tanks one gauge for each tank is
 recommended. They should read “FULL” at 80% of the tanks contents.

  COMMISSIONING, MAINTENANCE AND INSPECTION

 
 Installation and Commissioning
 Installation and commissioning of the fuel supply system should only be carried out by and
 supervised by LPGA “Approved” competent persons adequately trained in LPG automotive installation work and conversant with the properties of LPG.

 Leak Test.
 Except as described below , the complete system, including the tank(s) and all joints,
should be tested with air or inert gas at a pressure not less than 6 bar gauge, but not
 more than 90% of the fuel tank design pressure. Soap solution or a proprietary leak
detection fluid, or other method of at least equal sensitivity, should be used.

 If the fuel tank(s) and fittings are tested independently of the remainder of the system,
 and charged with LPG, the remainder of the system should be tested separately as above
 before connection to the tank(s) and the final connection(s) then leak tested at the
available tank pressure.

 Charging the Fuel Tank and System with LPG.

 Subject to the elimination of all leaks, the fuel tank(s) may be charged with LPG. It is
 good practice to reduce the oxygen content of the tank(s) to 10% or less by volume before introducing LPG. This can be achieved by introducing an inert gas eg, nitrogen or carbon dioxide dilution of the air in the tank(s) until the required end point is reached. When charging the tank(s) with LPG, the inert gas/air/LPG  vapour, should be vented or discharged in a safe place into the open air, and away from any sources of ignition. This shall continue until the inert gas/air has beeen eliminated.

 Testing the Fuel System.

 A final leak test should be carried out on any joints not previously tested under LPG
pressure, once LPG has been introduced.
Testing of controls under static conditions may be undertaken at this stage.

  Road test.
 Following the engine tuning, the vehicle should be given a thorough road test for
 satisfactory performance. Bi-fuelled vehicles should be subjected to fuel change over
 tests to ensure smooth transition.


 Final Certificate and Documentation.

 A competent person responsible for ensuring compliance with the Code of Practice and
 relevant Statutory Regulations should, upon satisfactory completion of all tuning and
tests, issue a signed certificate of conformity for the purchaser.
The vehicle owner should be provided with a Drivers Operation Manual which should include the Certificate of Conformity with a recommendation that this is carried in the vehicle at all times, for examination by authorised enforcement agencies.
 The vehicle owner should be informed that the Department of Transport, DVLA, need to be notified of the material change to the vehicle which must be noted on the vehicle
registration document.

Vehicle owners/operators need to ensure that a Special Vehicle Order has been obtained for any feature of the vehicle fuel system which does not comply with the Road Vehicle
(Construction and Use) Regulations 1986 or as amended. See “Foreword”.

 Passenger Service Vehicle (PSV) operators need to apply to the Department of Transport
 Vehicle Inspectorate, Swansea, to ensure the Certificate of Initial Fitness is valid for
 putting the LPG fuelled vehicle into service.

[Martin_1962]

Vehicle Marking.

 LPG powered vehicles should be fitted with a conspicuous durable marking informing that the vehicle operates on LPG and indicating the tank location and the position of the shut-off valves. The marking shall be of a durable type material. The marking should be displayed at the front and rear of the vehicle. The preferred locations are adjacent to the excise tax disc on the front of the vehicle and on the off-side windscreen at the rear of the vehicle.

 Maintenance and Inspection.

 The service manual for LPG fuelled vehicles should specify regular service requirements for the LPG fuel system or the additional requirements in the case od bi-fuelled vehicles.

 Every service shall include a check of the condition of all valves and connections for corrosion, damage or leakage, and corrected or replaced as necessary.
 
At 5 year intervals – Flexible pipework should be replaced unless proved suitable for further service.

   Fuel Tank(s).
 Examinations and tests shall be carried out by a competent person.
Every 5 years an external visual examination shall be made of the tank(s) and its fittings including the pressure relief valve, for signs of deterioration, corrision or leakage.

 Every 15 years  -   The tank(s) shall be subjected to an hydraulic pressure test and marked with the date and the testing authority symbol.

 The accuracy of the 80% stop fill valve should be verified whenever the fuel tank is emptied by using a re-fuelling meter.

  Garaging, Repair and Maintenance.

 Vehicles fuelled with LPG may be parked, serviced and repaired inside garages provided that the following conditions are observed:-

 Only trained and competent personnel on the use of LPG as a road vehicle fuel should be allowed to work on the vehicle engine or fuel system.

 There shall be no leaks in the fuel system and the fuel tanks shall not be filled beyond
 the 80% maximum level.
 Such vehicles shall not be parked within 3m of sources of heat, open flames or other
 sources of ignition.

 LPG fuelled vehicles being repaired in garages, unless the fuel is required for engine operation, shall have the fuel tank(s) shut-off valve closed and the LPG fuel in the service line exhausted by running the engine or, if this is not possible, by disconnecting, in the  open air, where the LPG cannot accumulate.

 Vehicles undergoing repairs involving welding or the application of heat, to any part within 1m of the fuel tank, shall have the fuel lines emptied and the tank removed or shielded from the source of heat.
 If the vehicle is to be repaired over an open pit, the pit shall be adequately ventilated.
It is recommended that lighting needs to be safe to use in a zone 2 area and that gas
detectors are permanently fitted at the bottom of the pit.

These should be checked daily.
Vehicles shall not be put through a low bake repainting oven or similar heating process unless the entire LPG system is safely removed or rendered gas-free.

 

[Martin_1962]

Transfer and Refit of the LPG Fuel System.

 
Whenever this takes place, the completed system should be tested and inspected prior to re-installation and rectification work, as necessary, carried out.
 Demounted fuel tanks containing LPG should be handled with care and stored in accordance with Code of Practice No. 7.
 All non-flexible pipelines should be replaced.
All flexible liquid phase hoses over 5 years old should be changed or re-tested in accordance with production proof tests in BS4089 or equivalent.

 Consideration should be given to exchanging the relief valve of the fuel tank whenever it
might be refitted to a different vehicle or if vehicle ownership changes, whether or not this coincides with a 5 or 15 year inspection.

 Vehicle Scrapping.

 
LPG fuel tanks must be removed from a vehicle before the vehicle is sent to be scrapped. Tanks should be handled with care and stored in accordance with Code of Practice No. 7 – “Storage of full and empty LPG cylinders and cartridges”. Tanks to be scrapped shall be destroyed in accordance with BS5430 by or under the supervision of a competent person and in a manner rendering them unserviceable for holding gas.

  Hotwork.
No hotwork eg, welding, cutting or bending should be carried out on vehicles unless the risk of affecting the LPG tank or system has been eliminated. This may require the removal of the tank or system.

 
 APPENDIX  1
 
 PROPERTIES AND HANDLING LPG
   All persons concerned with the storage and handling of LPG should be familiar with the
following characteristics and hazards:-

 LPG is stored normally as a liquid under pressure, is colourless and its weight as a liquid
 is approximately half that of an equivalent volume of water.
 LPG vapour is denser than air, commercial butane being about twice as heavy as air and
commercial propane about one and a half times as heavy as air. Therefore, the vapour may flow along the ground and into drains, sinking to the lowest level of thesurroundings and be ignited at a considerable distance from the source of leakage. In still air any vapour will disperse slowly.

 
When mixed with air, LPG can form a flammable mixture: the flammable range at ambient temperature and pressure extends between approx. 2% of the vapour in air at its lower limit and approx. 10% of the vapour in air at its upper limit: within this range there is a risk of explosion. Outside this range any mixture is either too weak or too rich to
propagate flame, butat atmospheric, the upper limit of flammability is increased but the increase with pressure is notlinear.
 Small quantities of the liquefied gas can give rise to large volumes of vapour/air mixture
and thus cause considerable hazard. A suitable, properly calibrated explosimeter  may be used for testing the concentration of LPG in air. ON NO ACCOUNT SHOULD A
NAKED FLAME BE USED TO DETECT A LEAK.

 LPG vapour is slightly anaesthetic and may also cause suffocation if present in sufficiently high concentrations.

LPG is normally odorised before distribution by the addition of an odorant such as ethyl
 mercaptan or dimethyl sulphide, enabling detection of smell of the gas as concentrations
down to one-fifth of the lower limit of flammability (ie,approximately 0.4%of the gas in air). Escape of LPG may be noticeable otherwise than by smell. When the liquid evaporates, the cooling effect on the surrounding air causes condensation and even freezing of water vapour in the air. This effect may show itself as frost at the point of escape and thus make it easier to detect an escape of LPG. Because of the refractive index of LPG, leaks can sometimes be seen as a “shimmering”.

 
APPENDIX    -  REFERENCES
 
STATUTORY INSTRUMENTS ETC.

 The Public Vehicle Act 1981
The Road Vehicle (Construction and Use) Regulations 1986 (and Amendments)
The Public Service Vehicle (Conditions of Fitness, Equipment, Use and Certification)
 Regulations 1981 ECE Regulation 67
The Department of Transport Vehicle Inspectorate, Swansea.

 STANDARDS.

 BS 4089                Specification for hoses and Hose Assemblies for Liquefied
                               Petroleum Gas.

 BS 5045                Specification for Steel Containers of 0.5 L up to 450 L

  Part 2                   Water Capacity with Welded Seams.

 BS 5430                Periodic Inspection, Testing and Maintenance of Transportable gas Containers (Excluding Dissolved Acetylene   Containers).
BS 6362                Specification for Stainless Steel Tubes suitable for Screwing
 In accordance with BS 21. Pipe Threads for Tubes and  Fittings Where Pressure-Tight Joints are made on the Threads

 BS 6956                Jointing Materials and Compounds
 Part 6                  Jointing Compounds for 3rd Family Gases
Part 7                 Anaerobic Jointing Compounds for 3rd Family Gases
 EN 549                 Specifications for Rubber Materials for Seals and Diaphragms
 For Gas Appliances and Gas Equipment

 Pr EN 751              Jointing Compounds (will supersede BS6956)
DIN 1787               Copper – Half Finished Products.
DIN 17671              Wrought Copper and Copper Alloy Tube Properties
ISO 8789                Rubber Hoses and Hose Assemblies for Liquefied

                                Petroleum Gas in Motor Vehicles. Specification.

 
 CODES OF PRACTICE.
LPGA COP 15            Valves and Fittings for LPG Service
 Part 1                   Safety valves.
 LPGA COP 7               Storage of Full and Empty LPG Cylinders and Cartridges.

 FOREWORD

[Martin_1962]

 FOREWORD
 
This Code of practice has been drawn up in consultation with the department of Transport. Motor Vehicles in the UK are required to comply with Road Vehicle (Construction and Use)
Regulations 1986 which includes specific requirements for LPG fuelled vehicles. These are supplemented by further requirements if they are to operate as Passenger Service Vehicles which are set out in The Public Service Vehicle (Conditions of Fitness, Equipment, Use and Certification) Regulations 1981.

 All the above apply both to original manufacture and to subsequent modifications, such as LPG conversions.
An amendment to the 1986 Regulations during 1997, will, it is anticipated, mean that
compliance with this Code of Practice will also mean compliance with those Regulations.
 Vehicles which do not comply with the 1986 Regulations, as amended, may only be used on the road by virtue of a “Vehicle Special Order” issued under Section 44 of The Road Traffic Act 1988 by the Department of Transport – Vehicle Standards and Engineering Division.


END OF COP11

[Martin_1962]

I suggest you cut and paste COP11 into one document!!!!

[Martin_1962]

As you can guess a lot of professional installs will not go through this, also why replace perfectly functional hoses.

I have seen no installs with the marked cut off vavles

[Martin_1962]

True. There's not a lot to be achieved by getting it going now if that's the final aim.

Before you start putting bits into the new car it'd be worth lining up someone who'd be prepared to certify it and reading up on all the rules and regs, and maybe discussing your intentions with them because there are bound to be loads of do's and don'ts.

Kevin

I think Martin knows someone who can certify it, in Church Lench?

I will certainly read the LPGA CoP...

Bernard - I gave you his number

[TheBoy]

TheBoy goes and orders some more disk space after Martin Imber's mega postings  

[Martin_1962]

TheBoy goes and orders some more disk space after Martin Imber's mega postings  

 

It is only COPII