Summary of investigations
From our initial investigations conducted during the visit to Alice Springs in March, follow up telephone conversations and subsequent discussion with industry specialists and experts the following is a summary of our investigation;
1. we were unable to find or inspect engines that claimed to have failed using Opal.
2. we were unable to find evidence of generator set failures that have been reported as being caused by Opal fuel.
3. we were unable to find evidence of Opal induced motorbike failures that had been cited by some parts of the industry.
4. there were no instances cited by repairers of vehicles <10 years having any faults attributed to Opal.
5. 4 out of the 15 repairers visited said that they had seen an increase in fuel pump replacement for seepage and with one repairer having had 13 incidents in the preceding two weeks. Part suppliers did not experience a significant increase in fuel pump sales during the same period.
6. of the failed fuel pumps that were inspected all appear to have failed either because of age or manufacturing related faults.
7. the one incident of a vehicle operability problem was after investigation attributed to a dirty fuel injection system.
8. Black discolouration reported in Opal fuel is the product of a chemical reaction in the fuel that produces hydrogen peroxide which can attack rubber and leave the black deposits and discolouration. This condition is common to all fuel and not just Opal.
9. The work conducted on petrol station fuel dispenser pumps was not because of faults induced in the pumps by Opal but as a result of preventative work consistent with standard practice when a fuel specification is changed.
Advice to motorists
On the basis of discussions with industry, our observations and tests we do not believe member’s vehicles will be damaged by the use of Opal and more specifically they should be advised;
1. Opal does not appear to pose a risk to vehicles designed for 91 RON fuel nor have we seen any examples of damage caused by using Opal.
2. that although low aromatic fuel is known to effect the rubber material that is often used in fuel pumps and cause them to shrink we saw no evidence that this effect has caused a fault in vehicles.
3. Opal may have a negative effect on the idle quality of some older vehicles with carburettors. However anecdotally this condition appears to have remedied with normal servicing and tuning.
4. the additional cost of using PULP in vehicles that can operate on Opal is not warranted.
There appears to be no technical reason why those vehicles that can use Opal should not use Opal. The community and the motor vehicle repair industry have been very cautious in their approach to the use of Opal but from our investigations there is no good reason why this reluctance should continue, especially when the RAA Technical Department Opal fuel investigation 2007
additional cost of using PULP is considered. We will continue to monitor the situation in Alice Springs and will encourage those with further concerns to ring the AANT Technical Advice telephone line 1300 661466. Although this is a general summary the authors are happy to discuss the detail of their investigation with others if needed. They can be contacted on 08 82024682.