Mercury Opti XS motors

[Hot Stuff]

Some tips on Optimax`s.

* The older 250 Opti could have a mis-fire at high RPM, thes was brought on by either spark plugs or bad grounding on the coil plate, some of you would have noticed that they lost the Coil drivers and went back to normal coils.( Keep changing plugs every 100 hours )
* They also changed the geometry of the intake ( Front half of the crank case )in 2006 due to oiling and oil bleed problems, its not difficult to get hold of a newer type intake and modify the oiling channels. This caused over oiling on some and under on others.
* The direct injectors may have a build-up of dirt, additives etc. that forms around the pintle or its passage, this causes the direct injector to lean out . We run the Quicksilver fuel system cleaner on all our motors and up to now have not had any issues. If you have a Opti that shakes around at idle this can also help, moisture in the system will effect # 5 and 6 direct injectors causing them to drip and cause a flooding effect on a cylinder.
* Alcohol, good for us not good for Optimax`s..... If your motor is a few years old replace and service the complete fuel system, fuel lines , lift pumps , VST floats, all the rubber grommets in the VST, tracker valves and "o" rings on the directs and fuel injectors. The Alcohol eats away at the components and could cause a very difficult problem or damage.
* Many high performance motors will not have the compressor air filter fitted due to the RPM`s they run but you wish to install one ask a dealership for the latest upgraded type ( canister type ) and plumb it in, its two pipes and thats it.
* Service the poppet valve, notice that it is next to number 5 cylinder? Change the spring and diaphram too, if it opens too easily you will loose water pressure and 5 cylinder will not be cooled sufficiently.
* The compressor recieves water from a fitting in the mid section, this has a strainer on it that may become blocked with weed or debris, if you have compressor overheat problems , check this first.
* I know merc oil is expensive, but try and stay with the Premium Plus or if you run hard the DFI synthetic.

Hope this helps a bit , cheers



By the way, we have a 300XS that has gone down three times while racing, and its still running 100%, Opti`s cant be that bad ??

[XstreamVking]

Optimax motors are great.. Thanks for the good advice! Keeping up with preventative maintainance is critical. Have two, one has 2000 hrs and still runs good. One has 1000 hrs and still has like new performance...