Merc Optimax Issue

Discussion in 'Boats and Motors' started by c. j. stone, Aug 5, 2008.

  1. Anyone have any repair issues with early 2000's Mercury Optimax engines? Particularly fuel injectors?? OR, any problems noted dealing with Mercury Customer Service/Relations Dept.??? Just curious. Thx.
  2. Workdog

    Workdog "One More Time"

    From when Opti's first came out in 98 or 99 thru 2001 or 2 there were big problems with the 150s - 200s. Since then, Optimax has been considered a very reliable mill. Evinrude ran into the same problem with their first FICHTs, as did Yamaha DFIs in the 250 and 300 range which blew frequently (there were so many problems with 300s that Yamaha set a repair quota, with Florida and southern states getting preferential treatment for a period of time). I recommend you go to and do a search for Optimax. You will find your answers, and more than you want to hear about early Optimaxes. I'm not bashing here. I own twin Merc EFIs myself.

  3. Actually when the big block (175, 200 and 225 HP) Optis came out in 98, they were nearly flawless. The 99's (I have one) were the same solid engine. In 2000, they "leaned" the oil injection to meet more stringent Federal regs and subsequently had a number of powerhead/injector failures on he '00 thru '02 model year Optis. Since then they have made changes to the fuel delivery system that has them rated near or at the top in reliability.

    I've "heard" various stories about Merc's Customer Service on the "bad" Optis ranging from nightmarish (denying service) to the opposite end of the spectrum where they replaced powerheads that were already out of warranty. Personally I'm don't think that I would buy an '00 to '02 Opti (big block). Never really heard of any problems with any the small blocks (90-150 HP).

  4. UFM82

    UFM82 The one others want to be

    As stated, late 90's/early 2000 models were prone to dying early deaths. Lean conditions, tolerances wrong and a lot of operator error caused issues. The main error many boaters caused themselves was not letting the engine warm completely before going WOT. Tournament guys were blowing them left and right with their style of start/floor it immediately. The processor wasn't flowing fuel properly and they would go lean and then POW they'd go bye-bye. Also as stated, most other makers had issues as well.

    If the engine has been well cared for and maintained properly and you are a careful driver, it could be OK but if you had a choice, I'd look for something after 2003 or later.

    As far as service goes, you'll get nothing from Merc now on an older outboard. They've washed their hands if it's out of warranty.

  5. I think there was a class action lawsuit(Opti owners vs. Mercury) couple years back but not sure if that is still active or not. If the owners won, I would think Mercury should still be on the hook for re-embursements? After all, Firestone had to replace all the bad tires they had problems with. (Slight difference in price!!) Just weighing options and trying to form an opinion of these motors/manufacturer.
  6. CJ,

    Do you have a '00-02 Opti big block or are you looking at buying one (or neither)?

  7. I have a 2001, 135 HP, 130 hrs. Googled "optimax problems" and got a lot of good-and bad opinions mostly from sites similar to this one. Just wondering what I might have to look forward to, and what to expect if I try to deal with the factory in the future. Seems the major issues were with the larger engines as mentioned below.
  8. You'll be fine. Enjoy the motor. The 135 is supposedly the best selling, most dependable Merc motor out there.
  9. cj,

    From what I've read and heard of from people that own the 135 Opti, it's a great running engine. One tip I'd give to anyone (no matter what brand engine) is to run the engine a minute or two before going to WOT, longer if the water is very cold. This will prevent "cold seize", a condition where the piston/rings heats up and expands more rapidly than the surrounding cylinder walls, thus causing the piston to seize. Properly cared for, that Opti will last you many years.

  10. I have a 2005 115 opti , one screamin motor , just let it warm up while your parking the car ,
  11. downtime8763

    downtime8763 Retired UPS

    I had a 2000 115 opit that I found out after I had issues with, it was only in production about a year and a half.I now have a 150efi thanks to them if that tells you anything and I love this motor, still have the shop and parts books for the opti if anyone is interested.