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Results 1 to 21 of 21
  1. #1

    Default 2004 Mercury 225 Optimax

    Was in a Bass Tournament cruising along at 5400rpm, suddenly the motor cut back to 4600rpm. All my safety gauges came on and she shut down to 1000rpm. We safely trolled it back to the boat dock and got it to a marina. Just curious about what happened. The certified Merc dealer will not be able to get to it until Thurs or Fri and I am clueless as to what might have happened. This motor has less than 70hrs on it......real curious!!

  2. #2
    Join Date
    Sep 2010
    Location
    Jersey Shore
    Posts
    3,203

    Default Re: 2004 Mercury 225 Optimax

    Does the boat have smart craft gauges or standard analog gauges? What alarm came on? Over heat or oil?
    Chris
    Dockside Marine Services
    Jersey Shore.
    Let the insanity begin.

  3. #3

    Default Re: 2004 Mercury 225 Optimax

    It has smartcraft guages. Alarms went off for the oil and engine.

  4. #4
    Join Date
    Sep 2010
    Location
    Jersey Shore
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    3,203

    Default Re: 2004 Mercury 225 Optimax

    If the oil in the tank on the engine is full, there is a good chance that tank needs to be replaced. The float inside the tank gets heavy with oil and sinks to the bottom setting off the alarm. It is almost never just the sensor. This is a common problem with the Optimax.
    Chris
    Dockside Marine Services
    Jersey Shore.
    Let the insanity begin.

  5. #5

    Default Re: 2004 Mercury 225 Optimax

    So would this have made smart guage go haywire? I did notice oil leaking from the cap when I took the crowl off to check out everything.

  6. #6
    Join Date
    Sep 2010
    Location
    Jersey Shore
    Posts
    3,203

    Default Re: 2004 Mercury 225 Optimax

    Oil should not be leaking at all.
    Chris
    Dockside Marine Services
    Jersey Shore.
    Let the insanity begin.

  7. #7

    Default Re: 2004 Mercury 225 Optimax

    Yes, that is what has scared me. It was noticed around the cap after this happened. I just hope I have a honest technician. When I took it to the marina the tech said it could be upwards of $2600., but he wouldn't know until he ran diagnostics on it. Don't get me wrong, I am in bass tournaments around here and that motor has never had any problems moving my 929 along, wouldn't trade it for the world, but I have never experienced anything like this happening and have always owned Merc's. She was running good this day, and yes I had just filled her with oil. Just upsetting having to hand crank her onto the trailer and not knowing anything til Thursday is going to drive me crazy.

  8. #8
    Join Date
    Sep 2010
    Location
    Jersey Shore
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    Default Re: 2004 Mercury 225 Optimax

    Let them run a diagnostic on it and report back with the findings.

    "When I took it to the marina the tech said it could be upwards of $2600" The tech should not have said this to you. It's like they are preping you for a screwing, especially without any diagnostics performed yet.
    Chris
    Dockside Marine Services
    Jersey Shore.
    Let the insanity begin.

  9. #9
    Join Date
    Sep 2010
    Location
    Jersey Shore
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    3,203

    Default Re: 2004 Mercury 225 Optimax

    Quote Originally Posted by grinnin33@yahoo.com View Post
    Was in a Bass Tournament cruising along at 5400rpm, suddenly the motor cut back to 4600rpm. All my safety gauges came on and she shut down to 1000rpm. We safely trolled it back to the boat dock and got it to a marina. Just curious about what happened. The certified Merc dealer will not be able to get to it until Thurs or Fri and I am clueless as to what might have happened. This motor has less than 70hrs on it......real curious!!
    BTW, 5400 rpms is not cruising, that is almost WOT.
    Chris
    Dockside Marine Services
    Jersey Shore.
    Let the insanity begin.

  10. #10
    Join Date
    Aug 2006
    Location
    SW Ohio, USA
    Posts
    10,328

    Default Re: 2004 Mercury 225 Optimax

    I agree w/Chris...I want to punch a tech like that right in the GD mouth when they come back w/BS scare tactics. You could disconnect the oil tank level switch to see if the alarm stopped...that would tell you if the switch could be the problem. Then check the switch wires for continuity w/an ohmmeter to prove it is closed and setting off the alarm especially if there is plenty of oil in the tank. To stop the oil seeping around the fill cap I replaced the "O" ring...bought it at an autoparts shop. You can buy the cap/dipstick combo from merc.
    Fix minor things (replace wear items for preventative maintenance.) that cause major problems before they break.

  11. #11
    Join Date
    Sep 2010
    Location
    Jersey Shore
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    Default Re: 2004 Mercury 225 Optimax

    Actually the circuit goes open to set the alarm. You would have to disconnect the sender wires(No worries they have bullet connectors) and make a jumper for it. If the alarm does not sound then the tank needs to be replaced.
    Chris
    Dockside Marine Services
    Jersey Shore.
    Let the insanity begin.

  12. #12
    Join Date
    Aug 2006
    Location
    SW Ohio, USA
    Posts
    10,328

    Default Re: 2004 Mercury 225 Optimax

    Thanks...I stand corrected.
    Fix minor things (replace wear items for preventative maintenance.) that cause major problems before they break.

  13. #13
    Join Date
    Sep 2010
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    Default Re: 2004 Mercury 225 Optimax

    It's just fresh in my mind as I just did this job a few days ago.
    Chris
    Dockside Marine Services
    Jersey Shore.
    Let the insanity begin.

  14. #14
    Join Date
    Aug 2006
    Location
    SW Ohio, USA
    Posts
    10,328

    Default Re: 2004 Mercury 225 Optimax

    I just looked at my merc. manual wire schematic and see the switches and alarm. They are both grounded and connect parallel via the tan/blue wire to the horn which is connected to 12 VDC via a purple wire. It seems confusing that the switches would be NC and have to open the circuit to set off the horn which has a 12 vdc source espcially since the key switch tests the horn.
    Fix minor things (replace wear items for preventative maintenance.) that cause major problems before they break.

  15. #15
    Join Date
    Sep 2010
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    Jersey Shore
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    Default Re: 2004 Mercury 225 Optimax

    Quote Originally Posted by guyjg View Post
    I just looked at my merc. manual wire schematic and see the switches and alarm. They are both grounded and connect parallel via the tan/blue wire to the horn which is connected to 12 VDC via a purple wire. It seems confusing that the switches would be NC and have to open the circuit to set off the horn which has a 12 vdc source espcially since the key switch tests the horn.
    The sensor on the tank has two blue wires.
    Chris
    Dockside Marine Services
    Jersey Shore.
    Let the insanity begin.

  16. #16
    Join Date
    Aug 2006
    Location
    SW Ohio, USA
    Posts
    10,328

    Default Re: 2004 Mercury 225 Optimax

    Correct...they transition to the tan/blue wire. I've been up now for 37 hrs straight and need to go to bed. Thanks and goodnight all. Going to install a water impeller kit tmrw...was too tired today even though the sun was bright and the temp. was in the 40s F. Another week or so I will be back on the water fishing for jumbo female walleyes!
    Fix minor things (replace wear items for preventative maintenance.) that cause major problems before they break.

  17. #17

    Default Re: 2004 Mercury 225 Optimax

    The Merc Tech at the Marina just called and said that the diagnostics was done. He is stratching his head, he contacted Merc and they have ask for the ECU. They are going to test it for free and respond to the Tech with their results. If the ECU needs replaced I am looking at around 2300 for replacement, if it is not the ECU then 125. an hour to find the problem. Was told that all alarms went off, trim, oil,etc.....hmmmmm. He assured me he checked the oil tank on the engine.....

  18. #18
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    Default Re: 2004 Mercury 225 Optimax

    Did all the alarms just sound or did they set codes?
    Chris
    Dockside Marine Services
    Jersey Shore.
    Let the insanity begin.

  19. #19

    Default Re: 2004 Mercury 225 Optimax

    Didn't alarm, but he said they sent codes. He said he has been on the phone with Merc 5 times today to try to troubleshoot that is why they ask for the ECU???

  20. #20
    Join Date
    Sep 2007
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    1,068

    Default Re: 2004 Mercury 225 Optimax

    The first thing I would do is check/replace that tank and sensor. You do not need an ECU.
    But if the motor cut back to idle than than that could also mean that oil pump stopped injecting for some reason. That would indicate a wiring problem running to the pump from the ECU. Less likely.
    Last edited by timebandit; 03-05-2012 at 10:38 AM.

  21. #21
    Join Date
    May 2010
    Location
    Indian Rocks Beach
    Posts
    2

    Default Re: 2004 Mercury 225 Optimax

    I have exactly the same engines... '04 Opti 225s. Both have experienced exactly what the others have described. In both cases, it was the float and the tank needed replacement. I do now have a spare sensor because that is an easy and cheap fix should that happen. To the point of the oil leaking out the top. These systems are (to the best of my knowledge) pressurized oil systems. You should have oil to the top of the on engine resevoir. If you do not, you can bleed the system per mercury manual. If you have oil to the top... and a loose cap, you will get oil out of the cap continuously. You can reset the oil alarm (again, procedure in manual) by activating the throttles with engine off but key on. Love my engines too...but they are noisy.

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