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'66 cj5 - what oil grade? and plug gap?

Discussion in 'Early CJ5 and CJ6 Tech' started by Jville, Dec 21, 2008.

  1. Jville

    Jville New Member

    thanks for the help
     
    Jville, Dec 21, 2008
    #1
  2. Glenn

    Glenn Kinda grumpy old man Staff Member

    Need some more info. What engine, where do you live? What is the temperature?
     
    Glenn, Dec 21, 2008
    #2
  3. w3srl

    w3srl All-around swell dude Staff Member

    What Glenn said.

    You can also find basic info like this in a factory service manual, which can be invaluable as you rebuild/tinker with any old Jeep. Reprints of the FSM can be found at just about any Jeep parts supplier.
     
    w3srl, Dec 21, 2008
    #3
  4. Eaallred

    Eaallred Member

    http://www.earlycj5.com/tech/general/Owners_Manual/1960/1960%20CJ5%20CJ6%20Owners%20Handbook%20Pages%2011%20to%2020.pdf

    According to Jeep (Assuming the stock F-head),

    Not lower than 32 degrees, 30W or 10w30

    Not lower than 10 degrees, 20, 20w, 10w30, or 10w20

    As low as -10 degrees, 10w, 10w30, or 10w20

    Below -10 degrees, 5w, or 5w20

    So according to Jeep, it looks as though 10w30 is probably our best choice for oil unless you are going below -10 degrees. Unless your engine is worn out and can't maintain proper oil pressure, then a thicker oil can be a band-aid to get you by.

    Minimum oil pressure spec is 10psi per 1000rpm. Running a really thick oil that far exceeds this results in more oil getting dumped out the oil pressure relief back to the sump, rather than having it flow past the bearings. Thicker oil is definitely not always better.

    .030" gap on a stock system. Tighten the gap a bit if your plugs are not burning clean, open the gap a bit if you are running a CDI system (MSD, Jacobs, Mallory, etc).
     
    Eaallred, Dec 21, 2008
    #4