Mercury Optimax '05 150?
12-13-2013, 08:43 AM
#1
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Mercury Optimax '05 150?
Don't really know too much about outboards. I'm looking at an '05 fishing boat with a 150 hp Mercury Optimax. Do the Optimax motors have a good reputation?
12-13-2013, 09:15 AM
#2
That depends on how well it is taken care of and whether it has had upgrades to take care of the issues common with them.
Air compressor that runs the fuel injection only has an expected life of a few years so I would look into that. Any fuel lines with red lettering on them from mercury are no good and need to be changed if not done already as ethanol breaks them down and will clog the fuel system.
Oil tanks are under the cowl making them look enormous and they leak when tilted all the way if full of oil.
Good power stock up to 5750 rpm and suprisingly quiet operation for a 2 stroke.
Computers can be sent out and flashed to make more power without any engine mods for about $600.
For the few issues they sometimes have I am sure other brands could be far worse.
Definitely consider it but compression test for sure, it is a 2 stroke after all!
Air compressor that runs the fuel injection only has an expected life of a few years so I would look into that. Any fuel lines with red lettering on them from mercury are no good and need to be changed if not done already as ethanol breaks them down and will clog the fuel system.
Oil tanks are under the cowl making them look enormous and they leak when tilted all the way if full of oil.
Good power stock up to 5750 rpm and suprisingly quiet operation for a 2 stroke.
Computers can be sent out and flashed to make more power without any engine mods for about $600.
For the few issues they sometimes have I am sure other brands could be far worse.
Definitely consider it but compression test for sure, it is a 2 stroke after all!
12-13-2013, 11:01 AM
#4
I own both an opti as well as a 4 stroke and they are definitely different. All brands have their issues. You just have to properly maintain and service them.
I love 2 strokes, but my 4 stroke is almost silent at idle and you can have a conversation at WOT.
The optimax has the smoothest idle I have ever seen in a 2 stroke and does not smoke at all. I would just look it over. Priced right and well maintained go run it. You will probably like it.
I was just offering what I know about them.
I love 2 strokes, but my 4 stroke is almost silent at idle and you can have a conversation at WOT.
The optimax has the smoothest idle I have ever seen in a 2 stroke and does not smoke at all. I would just look it over. Priced right and well maintained go run it. You will probably like it.
I was just offering what I know about them.
12-13-2013, 02:49 PM
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Coil packs are a common item to fail also.
I run a 300 optimax (a lot of the components are the same as a 150).
These motors are a very very fuel efficient 2 stroke (comparable if not better fuel economy to any similar size 4 stroke and more punch and lighter).
They do have items like the compressor and coil packs that are prone to failure, however merc have upgraded the compressor internals and are getting better reliability now. Coil packs are simple and relatively cheap to replace.
One thing you find with the optimax motors is the engine management system is awesome at keeping the motor running smooth (especially at idle) even with an issue. I can disconnect at least 2 coil packs at idle and can't hear the difference in engine note!
I race mine hard and did smash a piston up (assumed broken ring), engine still ran and I drove it back to ramp under its own power.
As far as outboards go the optimax is one of the best, only thing better about a 4 stroke is its a little quieter.
Good luck
I run a 300 optimax (a lot of the components are the same as a 150).
These motors are a very very fuel efficient 2 stroke (comparable if not better fuel economy to any similar size 4 stroke and more punch and lighter).
They do have items like the compressor and coil packs that are prone to failure, however merc have upgraded the compressor internals and are getting better reliability now. Coil packs are simple and relatively cheap to replace.
One thing you find with the optimax motors is the engine management system is awesome at keeping the motor running smooth (especially at idle) even with an issue. I can disconnect at least 2 coil packs at idle and can't hear the difference in engine note!
I race mine hard and did smash a piston up (assumed broken ring), engine still ran and I drove it back to ramp under its own power.
As far as outboards go the optimax is one of the best, only thing better about a 4 stroke is its a little quieter.
Good luck
Last edited by Kurt Hamilton; 12-13-2013 at 02:51 PM. Reason: Typo
12-13-2013, 06:20 PM
#7
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agree coil (s) can be a problem and bad coil (s) can knock out the ECM. Also very easy fuel problems and so can the air compressor be a problem child. There was years the boost fuel pump was junk. They have fuel injectors and air injectors inwhich alot of times if the fuel has not been taken care of can cause both problems. Always wise to have them checked and flow tested to see if they need a cleaning.
You can test the fuel pressure and the air pressure with the proper guage. Readings for the air pressure should be 10 psi higher the fuel pressure if not you have a problem. If I remember correctly fuel pressure should around 80 psi and air pressure 90 psi. Also the tracker seems to be another problem. Sparks plugs are alot harder to change on the optis and the fuel water sep filter needs to be changed twice a year reguardless. It also has a sensor in the bottom of the spin fuel filter to detect water inwhich if it does have water, a warning horn will go off. Anyways just some jist about these motors. I use to sell these motors in a jetdrive / boat app but no longer, nor care to even work on them. IMO the Yamaha is the better outboard motor.
You can test the fuel pressure and the air pressure with the proper guage. Readings for the air pressure should be 10 psi higher the fuel pressure if not you have a problem. If I remember correctly fuel pressure should around 80 psi and air pressure 90 psi. Also the tracker seems to be another problem. Sparks plugs are alot harder to change on the optis and the fuel water sep filter needs to be changed twice a year reguardless. It also has a sensor in the bottom of the spin fuel filter to detect water inwhich if it does have water, a warning horn will go off. Anyways just some jist about these motors. I use to sell these motors in a jetdrive / boat app but no longer, nor care to even work on them. IMO the Yamaha is the better outboard motor.
Last edited by BUP; 12-13-2013 at 06:27 PM.
12-15-2013, 06:24 PM
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opti pop, I have worked on a lot of them,do a compression test first,be carefull putting plugs back in cuz its easy to cross thread. If compression is good,over 110 on those and even,just run the good dfi oil and fresh fuel and you be good to go. O and run it wide open often to keep it clean and free of too much carbon, just my 2 cents.
