Rod Bearing Replacement - When?

Discussion in 'Gen 1 & 2 - Engine, Exhaust, Drive Line & AC syste' started by turbo79, Jun 27, 2008.

  1. turbo79

    turbo79 SHO Member

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    I see a lot of discussion about replacing spun rod bearings in the Yamaha engines, so, when is this appropriate in an engine that's not raced or modified beyond a performance y-pipe?

    I have 145,000 miles on my '92, of which about 5,000 were put on by me.
     
  2. Phoenix

    Phoenix SHOHOLIC

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    Red oil light flicker at idle , and knocking (almost too late). Besides that its prevention , I suggest you do them before either one of those comes up.
     
  3. NebraskaSHO

    NebraskaSHO Harumph! Staff Member

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    I just bought a 93, and it made no noises or caused the oil light to flicker, but the RB's were the first things ordered.

    Right now it's torn apart getting ready for a 60k, and will be done as soon as the parts show up from RCM.
     
  4. RiceeatingSHO

    RiceeatingSHO Travis R

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    When to do rob Bearings?

    Now.



    haha
     
  5. SHOtime2511

    SHOtime2511 CGP

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    agreed.
    DO THEM NOW! some engines have spun bearings with less than 100K
    some have lasted 300K. why take the chance? it costs about $50.00 and takes a few hours of your time.
     
  6. jthod

    jthod Mr. Goodwrench Staff Member

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    There're here! Thanks Russ!
     
  7. marv

    marv SHO Member

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    Do them asap, if you plan on driving car hard you will learn the hard way (as I did) that spun bearings will happen, I will be ording my bearings also.
     
  8. AREA 91

    AREA 91 SHO Member Staff Member

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    I am a rod bearing advocate. I have at least 2 sets at my shop at all times.:angelnot:
     
  9. turbo79

    turbo79 SHO Member

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    I'm more or less convinced to do this soon.

    So, since I'm not really equipped to do such a job myself, due to lack of proper tools, proper lifting equipment and garaging (I understand you have to remove the sub frame to gain access - not me!):

    • any suggestions on finding a SHO-experienced mechanic in the Portland, Oregon area?
    • Is this mainly an issue with the OEM rod bearings and will proper replacements last longer than OEM?

    I'm grateful for any help or suggestions...
     
  10. 93rev2sev

    93rev2sev SHO Member

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    It's a driveway+handtools and a torque wrench job.

    Not a lifting equipment + subframe removal job.

    Any engine(no matter how well built) will wear the rod bearings out...eventually. Since our engines ARE so well built, there are lot's of very healthy engines that DO need their rod bearings replaced.

    It has become more common(and it's easier) than shimming the valves.

    You mentioned in your first post...
    When is a good time to replace a SPUN bearing...
    The answer is never. Replace them before they spin and you will not have a problem.
     
  11. SHOMurph

    SHOMurph Ford B@stard

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    Pretty much every SHO on the road nowadays needs rod bearings.

    More than likely you don't know how the previous owner's drove the car or change the oil.

    Change the rod bearings and no worries.


    Pretty much unless you have a good bit of mods...if you spin the bearings the car is done. Unless you love the car the money spent replacing the motor is more than the car is worth.

    Get 'em done peoples! I'm just about to do my wife's at 140k and I've changed the oil every 3k since 70k when I bought it.
     
  12. luigisho

    luigisho SHO Member

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    You can do this yourself. You need to remove the y-pipe and drop the oil pan. Let the oil on the rotating assembly drip off and give it a shot. It sounds like it's harder than it really is. There are a few write ups floating around to walk you through it.
     
  13. techi14

    techi14 SHO Member

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    I got them done as soon as I got the car. Had 135k on the originals, were showing some copper.
     
  14. Kens1992mtxSHO

    Kens1992mtxSHO Ken is a bad, bad boy and should be banned Staff Member

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    Brian recently did mine on my 92 with similar mileage to yours. They did not appear to be that bad but why take the chance...

    Thanks Brian !!!
     
  15. fitefanSHO

    fitefanSHO SHO Member

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    Why is the oil light flicker a sign of bad/going bad rod bearings?

    Are there any other signs?
     
  16. itwonder

    itwonder SHO Member

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    You can do rod bearings at any time, but it makes a lot of sense to do it at the same time you are doing a clutch job. All of the parts you need out of the way are out anyway, and there is extra room to work with the subframe out. IMO, rod bearing replacement is not an emergency unless you plan to abuse the engine as many SHO owners tend to do. I did mine at about 180K, and they were not that bad. Some babbit worn through to copper does not indicate a worn out bearing.
     
  17. jthod

    jthod Mr. Goodwrench Staff Member

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  18. fitefanSHO

    fitefanSHO SHO Member

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    Should I be worried? I don't beat on my car but I drive her hard sometimes.

    Does a "spun" bearing ruin the engine as a snapped timing belt might on some cars?
     
  19. Racer X

    Racer X SHO Pilot

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    A spun bearing will ruin the rod and crank if you're lucky.

    If you're unlucky, as some have been, you will snap the rod. Upon snapping, the rod will look for the quickest way out of dodge. That route invariably is through the side of the block. This may cause an oil leak, along with other internal engine damage.

    Rod bearing replacement should be a preventive measure. If it's a corrective measure, it's already too late.
     
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  20. revhardSHO

    revhardSHO SHO Member

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    A spun bearing will ruin the rod, cap and sometimes even the crank. This is because the bearing starts spinning and creates a metal on metal condition. Most of the time, you would scrap an engine with a spun bearing.

    Dont be worried. Just remember: high RPM is fine; the SHO can take 7000rpm all day long. Its the low rpm, low oil pressure condition (lugging) that eats rod bearings.
     
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