Bulletins & Advisories Recommendations and Adjustments for the Use of Unleaded Fuel

Discussion in 'Technical Articles' started by Service News, Monday 16th Feb, 2015.

  1. Service News Staff Managed Dealer Information

    From 1 January 2000 leaded petrol will not be available in the UK. The following information gives details of Honda vehicles affected by the withdrawal of leaded petrol, and where applicable the adjustments required for using unleaded petrol. Honda Cars are built with specifications which are consistent with the region in which they are to be sold. Movement of vehicles between areas is becoming more common, as is the importation of cars from totally different markets. One of the specifications which is area dependent, is the fuel type. It is therefore, possible to have a negative effect on the vehicle if the wrong type of fuel is used and various problems can be attributed to this.

    Using Unleaded Fuel in Vehicles Designed For Leaded Fuel

    1. Premature wear of valve seats.
    2. Lack of Power.
    3. Premature wear of bearings.
    4. Seizure of cylinder head components, piston or piston ring due to insufficient cooling.
    There are no problems of this type with 84Y Model Civic onwards or other models from 86Y Model.

    Using Leaded Fuel in Vehicles Designed For Uneaded Fuel

    1. Rapid deterioration of catalytic converter and oxygen sensor, causing emission test failure for cars equipped with such devices.
    2. Deterioration of engine oil due to presence of lead.
    3. Damage to cylinder wall (piston ring shape and material are different, leading to inflow of lead between piston ring and cylinder wall).
    4. Damage to main and con-rod bearings due to lead build up.
    5. Accumulation of carbonised lead in the combustion chamber causes early ignition leading to knocking and eventual holing of piston.
    6. Low compression due to carbonised lead build up between the valve and valve seat.
    The first symptom will be engine check lamp illuminated due to misreading of air-fuel mixture. Always check the Fuel Label on the inside of the fuel filler flap.

    Lead Replacement Petrol (L.R.P.) and Anti – Wear Additive (A.W.A.), hasl replaced leaded petrol. Some petrol stations sell L.R.P. others offer A.W.A. or both. It is not recommended to mix the two or alternate between them. Pumps dispensing L.R.P. will be clearly labelled and will have a wide nozzle that will not fit into the fuel filler of cars equipped with catalytic converters. A.W.A. is available in bottles or syringe – like injection applicators; and must be used by mixing with unleaded petrol. It is important to follow the manufacturer instructions exactly as stated on the packaging. The following tables gives details of Honda vehicles built up to, and including 1989YM designated for the UK market. They were built prior to the introduction of unleaded petrol into the UK. They also give details of any adjustments or recommendations for the use of unleaded petrol.

    Table 1 lists those vehicles, which from the year 2000 will not be able to use our previously recommended three tank fulls of unleaded petrol to one leaded. From the year 2000 these vehicles will require either L.P.R. or A.W.A.

    Table 2 lists those vehicles, which can run on 95 octane-unleaded premium petrol without adjustment or by retarding the ignition timing by 4 degrees from specified in the workshop manual. All the vehicles listed in table two are alsosuitable to run on 98-octane super-unleaded petrol without the need for any adjustments to the ignition timing.
  2. Ichiban Founder Staff Team

    England CJ Leeds
    Important Information for pour classic car owners this TSB was issues by Honda to all dealer way back in 29-09-03 TSB# HUK000000000193.

    Now you know why the classic CR-X are going bust.