1. Registration trouble? Please use the "Contact Us" link at the bottom right corner of the page and your issue will be resolved.
    Dismiss Notice

231 buick V6 Help needed ASAP

Discussion in 'Early CJ5 and CJ6 Tech' started by Mudweiserjeep, Dec 14, 2010.

  1. Mudweiserjeep

    Mudweiserjeep JEEP: Bouncy and Fun

    I have a 1979 231 Buick even fire V6 in my Cj5.
    I have lost oil pressure and lifters are knocking. Engine has been running great.
    Question: Does this sound like the oil pump is bad? It is located in behind the oil filter mount there at the timing chain?

    Any suggestion what to look for or to check?
    This is my primary transportation and I need to fix it fast.
     
  2. kaiser_willys

    kaiser_willys Well-Known Member

    ugg that dont sound good! did it do it all at once? could be a stopped up pickup screen if it did it all at once. I would think if it were the pump this would have showed up gradually. oil light or gauge?
     
  3. uncamonkey

    uncamonkey Member

    I had one set fail when the shaft that drives the pump started spinning inside the gear instead of turning it.
     
  4. mountainrat

    mountainrat New Member

    Pull the large bolt off of the housing to gain access to the relief spring and valve, clean out the bore and reassemble. My oil presure went away suddenly and I found a little crud in the bore, after cleaning everything is fine but it didn't run long with no presure.
     
  5. Mudweiserjeep

    Mudweiserjeep JEEP: Bouncy and Fun

    UPDATE: I pulled the oil pan and found what appears to be pieces of plastic ......... teeth of a gear? I pulled the oil pump and it looks fine. I haven't looked at the relief spring and valve yet.

    What has plastic gear teeth in a buick V6?
    Thinking distributer and timing..............but the jeep runs fine..........????
     
  6. Patrick

    Patrick Super Moderator Staff Member

    The original cam gear was nylon/ plastic, at least in the 225. I'm not certain about the 231, but I'd bet on it.
    Years ago I replaced many failed oil pumps in Ford inline 6's due to plastic timing gears coming apart and sucking into the oil pump. The 225 has a fairly fine screen on the pickup, and I assume the 231 does as well, so not sure how much debris can be pulled through.
     
  7. nickmil

    nickmil In mothballs.

    What Patrick said. The timing gears on the 231 were plastic or fibre as well. As he indicated, the oil pump pickup is pretty fine mesh. I believe there is a relief valve in it but I can't remember on that for sure. Hopefully not as they could allow debris into the oiling system. I'd definitely pull the timing cover and take a close look.
     
  8. Mudweiserjeep

    Mudweiserjeep JEEP: Bouncy and Fun

    Stupid question: Timing gears- Talking about timing chain gears?
     
  9. kaiser_willys

    kaiser_willys Well-Known Member

    yep, you already have the pan off so the timing cover should be even easier now. only other "plastic" in that motor that i know of would be the valve seals if it even has that type. they should be black in color. if the pieces are a light color its the cam gear
     
  10. Mudweiserjeep

    Mudweiserjeep JEEP: Bouncy and Fun

    The plastic pieces are a dirty brown color......Looks like I need to order the timing chain. My cam should be alright?
     
  11. kaiser_willys

    kaiser_willys Well-Known Member

    yes. this was a common problem back in the day. even on up into the mid late 80's buick engines. have seen it happen in other GM engines as well.