Mercury Surf Engine Specification relating to turning arc modification

Thursday, 14 June 2012


The standard turning arc of the Mercury Surf Engine is modified (increased) to enhance turning ability, whilst still allowing sufficient control for the Driver.

The original modification in 1998 was initiated by Westcoast Surf Marine Services as part of the surf kit installation.

The turning stops on the swivel bracket were modified to achieve an increase in the turning arc.

Unfortunately this modification also weakened the turning stops resulting in some damage/breakage under load.

It was recognised that this damage was not the fault of the user and subsequently damaged/broken turning stops were accepted during scrutineering at SLSNZ IRB Events.

In 2007 PSP Engineering was appointed to supply and fit Mercury Engine surf kits

To address the existing problem of weakenedturning stopstheswivel bracketis no longer modified.

Instead the V stop on the steering shaft assemblyis modified to achieve the same increased turning ability.

The result of this change means the swivel bracket turning stopsare not modified and therefore the risk of damage/breakage is removed.

The Issue

During the 2012 BP Surf Rescue NZ Championships several engines were found to have the swivel bracket turning stops intentionally removed or modified in order to gain an advantage.

No action was taken at the time due to previous history as mentioned.

It is now 5 years since the modification to theswivel bracketturning stops ceased including the potential of accidental damage to the turning stops.

A fair and reasonable phase out period is now completed and it is time for the scrutineering process to be inclusive of the engine turning arc.

Note: This is not a rule change or a new rule, it is simply applying the general heading relating to IRB Equipment on page 13 of the SLSNZ Equipment Specification Manual.

'The modifications to the listed equipment in this manual are the only modifications permitted to this equipment as received from the SLSNZ Approved Supplier/Manufacturer'.

There is no listed modification permitted to the engine turning arc, inclusive the swivel bracket and steering shaft assembly, therefore standardisation applies.


From July 2012 the engine turning arc will be checked for compliance during scrutineering at SLSNZ IRB Events.

Download this in a printable version (pdf, 150kb)

If you have any questions or concerns please contact Rescue Asset Manager, David Hickey 09 524 6641,