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Cat 3126 problems

Discussion in 'Engines' started by Dago By, Aug 5, 2008.

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  1. Dago By

    Dago By New Member

    Joined:
    Aug 4, 2008
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    1
    Location:
    Osage Beach
    I have a 1996 450 DA Sea Ray w/ 3126 Cat engines that have 337 hours on them. The starboard engine just broke a valve, scoring the cylinder wall and destroying the turbo. It is cheaper ( if you call $22,000.00 cheap ) to purchase a new short block. I know the engines are out of warranty as far as time is concerned, but shouldn't Caterpillar help with this in some way. I heard about problems on certain engines made in France during this time span......can anyone help with the affected serial numbers?
  2. Fishtigua

    Fishtigua Senior Member

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    Jul 20, 2007
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    Guernsey/Antigua
    I think, if memory serves me correctly, the Cat had a number of poreous blocks cast in Belgium; hardly in your problem sphere.

    Can you not just get a rebuilt cylinderhead and a cylinderliner and piston kit, new rods and rockers. Just done one on a Volvo KAD 300 for about $4000.

    Fish
  3. CaptTom

    CaptTom Senior Member

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    If I remember correctly, Cat had problems with their 3196 engines in the mid 1990's, something about a potential bad aftercooler making engines blow. Maybe a connection? Who knows. But Google aroumd and see what you can find. If there was a recall or known defect, maybe there's some help.
    Good luck.
  4. Capt J

    Capt J Senior Member

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    I can tell exactly what caused the problem. Lack of use with only 337 hours in 12 years. Have the engines been started and run long enough to reach temperature every two weeks? If not, rust will form on the valves, one will get stuck and, this happens. CAT is not liable in my opinion.

    I too think it would be much cheaper to have the cylinder head rebuilt and pop a liner and piston kit in the one cylinder. Parts should be around $800 for a cylinder kit, and just guessing a rebuilt cylinder head (a different one) should be no more then $4,000 plus labor.
  5. Loren Schweizer

    Loren Schweizer YF Associate Writer

    Joined:
    Apr 20, 2004
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    Location:
    Coral Gables/Ft. Laud., FL
    Hi Dago By and welcome to YF.
    Sorry to hear of your motor problems.
    Capt J ran some numbers for you, to which you'll have to add a rebuilt turbo.
    Now, what's to prevent the same thing from happening to the other engine? Need to double the dollar figure?
    BTW, in 1998, Cat came out with a three-valve head (with much improved breathing and hence able to meet stricter emission standards) and a host of other improvements--including a totally electronic governor--for the 3126B which supercedes your engines.
    If it were me, I'd call your local Cat distributor service dep't. and ask for some friendly advice regarding parts interchangeability between the 3126 and 3126B...at least as far as the heads go...if I were to keep the boat long-term.
    Or do the least work required per Capt J and sell the boat.

    See link:
    http://findarticles.com/p/articles/mi_m0FZX/is_n3_v64/ai_21201302
  6. SeaEric

    SeaEric YF Historian

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    Jan 28, 2007
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    Location:
    out on the dock
    The 3126's are not liner engines as far as I know. The cylinders may be able to be bored and sleeved, but the engine has to come out of the boat to do that. The reman blocks are likely sleeved and hence rebuildable in the future. I have had some tangential experience with 3126's, all of it bad.

    Given that your boat is a 1996, your engines may perhaps have the problematic "French" blocks. Have a Cat dealer run the serial #'s. If you scream loudly enough, you may get some help from Cat on parts. The labor will be on you. My customer with a 1996 Trojan 44 had this issue and Cat did help him out by providing remans. That was 4 years ago, give or take. Its worth a shot.