oil pressure change

Discussion in '40- & 55-Series Tech' started by fcgadget, Oct 27, 2005.

  1. fcgadget

    fcgadget

    Messages:
    310
    Media:
    4
    Albums:
    1
    Likes Received:
    12
    Joined:
    Jun 27, 2005
    Location:
    San Jose CA
    My newly installed used-but-ran-great F engine has a few problems. There are oil leaks which I'm methodically fixing and odd noises associated with the tranny or xfer. The real problem I think is the oil pressure. With a full load of oil the pressure is 40-40 lbs at start. After a casual drive down the hil I hit the freeway, about 15 minutes. The pressure remains god for about 5-10 minuites of freeway at 55-65 mph. Then the pressure drops to 30, with a drop to 10 when idling at a turnout. If the engine is shutoff for awhile, the pressure comes up some, maybe to 35-40.

    Any ideas? The leaks do drop the oil amount, but very minimally. What should I check/replace/blow-up?????

    1970 FJ-40 w/ 'new' '71 engine, 4 spd, manual xfer
     
  2. camcruiser13

    camcruiser13

    Messages:
    6,978
    Media:
    3
    Albums:
    1
    Likes Received:
    29
    Joined:
    Jun 22, 2004
    Location:
    sittin on the couch in UT
    i got a v8 and does the same thing when i first start it up the pressure is high then it chills out, no probs with it ever thought, so no biggie
     
  3. Poser

    Poser Oh...Durka Durka Durka. s-Moderator Supporting Vendor

    Messages:
    20,403
    Media:
    17
    Albums:
    1
    Likes Received:
    828
    Joined:
    Oct 1, 2003
    Location:
    MN
    Sounds normal for a used engine...


    What weight oil are you using?


    If it is light, 10-30, I would get 15-40 or even 20-50 if you are in a warmer area...


    I run 15-40 year round in my 2F


    Good luck!


    -Steve
     
  4. phishtaco

    phishtaco Cincinnati

    Messages:
    2,390
    Likes Received:
    91
    Joined:
    Aug 7, 2003
    Location:
    Cincinnati

    Sounds like what my F did......Then it started knocking....Now there is a 2f in it's place almost running good luck :frown:
     
  5. fcgadget

    fcgadget

    Messages:
    310
    Media:
    4
    Albums:
    1
    Likes Received:
    12
    Joined:
    Jun 27, 2005
    Location:
    San Jose CA
    I'm running 5-30, the temp is in the 50-60 range. My pressure just seems way too low 10 at idle and 30 at freeway speed!
     
  6. kruzinboots

    kruzinboots

    Messages:
    155
    Likes Received:
    0
    Joined:
    Sep 15, 2005
    Location:
    Topeka, Kansas
    It's nice to know that there are other V8's out there that do this. I'm wondering if on my next oil change, I should try some 15-40. I usually only drive it in the warmer weather.
     
  7. IDave

    IDave

    Messages:
    7,167
    Media:
    1
    Albums:
    1
    Likes Received:
    28
    Joined:
    Jan 3, 2003
    Location:
    McCall, ID
    That's way too light for your engine, IMHO
     
  8. brian

    brian SILVER Star

    Messages:
    9,060
    Likes Received:
    2,555
    Joined:
    Feb 7, 2003
    Location:
    lebanon,pa
    1. these are not race engines.
    2. these are closer to tractor engines.
    3. these use engine tech that was old, when these engines were new.....
    4. 10psi per 1000rpm is reguarded as fine, give or take a few rpms.
    5. step it up to 15w-40...yes that's dessiel oil...yes, lots of us use it.
     
  9. Eric Winkworth

    Eric Winkworth

    Messages:
    2,091
    Likes Received:
    8
    Joined:
    Mar 1, 2005
    I have not seen mine go below 25 even at the hottest temps, the old girl has 270 000kms, but then again she is a diesel
     
  10. Doug_S

    Doug_S

    Messages:
    880
    Likes Received:
    0
    Joined:
    Jul 19, 2004
    Location:
    Olympia, WA
    With a plain bearing engine like we have in the F and 2Fs you can run as low as 5psi when idiling. No biggie. 30-40 on the open road sounds fine to me.
     
  11. Pin_Head

    Pin_Head

    Messages:
    14,641
    Likes Received:
    2,278
    Joined:
    Feb 6, 2002
    Location:
    OC, CA
    I don't get too excited about what numbers the oil pressure gauge says as long as it is not zero. Think of it as an idiot light. The stock guage is a notorious liar and I have driven a few engines that had low oil pressure for many years. As long as all the bearings are geting oiled it is good.
     
  12. azlar

    azlar

    Messages:
    72
    Likes Received:
    0
    Joined:
    Aug 13, 2005
    Location:
    Tucson AZ
    I'm guessing that this is degrees C. Dino oil will start breaking down in the 210-220F range (~100C). So if this is your cruising temps/presure it doesn't seem seriously amiss for a used engine.

    I do agree with the other suggestions to use a heavier oil. 5-30 is great for Fairbanks in January, but kinda thin for the rest of the country.
     
  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.