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  •  » Low oil pressure at warm stop

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    8/29/2014 6:29 PM  #1

    Marlon66
    FYI FORD Member

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    From: NorCal, Bay Area
    Registered: 4/01/2013
    Posts: 25

    Low oil pressure at warm stop

    289 4v in a 66 running straight 30W(Royal Purple).  Oil pressure is great at start and about 33% at cruise, until it gets hot (temp indicator in the middle), then oil pressure sinks to near zero at stop.  If i put the car in the neutral the pressure rises back up to about 10%.  Does anyone know what could cause this?

     

    8/29/2014 7:04 PM  #2

    lowercasesteve
    Senior 24-7 FYI Addict

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    From: Auburn, Ca
    Registered: 4/01/2013
    Posts: 1,291

    Re: Low oil pressure at warm stop

    The stock oil pressure guage is not real accurate.  You can get a mechanical guage at your local parts dealer.  It will screw in just above the oil filter where the current sensor mounts.

    Normally with Windsors you will see 10psi/1000rpm when the engine is warm.  So, you should idle at 5-10psi oil pressure.  Measure yours to verify what you actually have.  Rev the engine and see what happens.  anything less than 20psi when the engine is revving good, will indicate a problem

    Low oil pressure can be caused by  many different things, but one of them is worn crank bearings.  bad bearings can sometimes be found by changing the oil and checking the old oil for copper flecks.  Kind of like gold in a pan when panning (I live in Calif gold country)

    Original owner - 351w,T-5, 4whl disks, power R&P
     

    8/29/2014 7:53 PM  #3

    Bullet Bob
    Senior 24-7 FYI Addict

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    From: Montrose, Colorado
    Registered: 4/01/2013
    Posts: 4,939

    Re: Low oil pressure at warm stop

    Is this a new development or on-going?  As stated, most Winsors don't have great oil pressure at warm idle.  Before I replaced it, our 289 did about what your's is doing so I asked my brother (Fox 5.0 and many years as a Ford parts counterman) about it.  He said his 90 GT, with 150K miles on it, had been doing the same thing since new and not to worry, so I didn't.  I later purchased the Fox and sure enough, warm idle would barely move the needle.  To my knowledge the car is still going strong with well over 160K on the clock.  If your's isn't rattling or having lifter noise at idle, don't worry about it as long as the pressure comes up off idle.

    BB

    Last edited by Bullet Bob (8/29/2014 7:54 PM)

    "you get what you pay for, good work isn't cheap, and there are NO free lunches...PERIOD!"
     

    8/29/2014 9:29 PM  #4

    MS
    Forum Originator

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    From: Canyon Lake, Texas
    Registered: 1/24/2013
    Posts: 12,688

    Re: Low oil pressure at warm stop

    My 427 stroker (Windsor based) has low oil pressure at idle, around 15-20 PSI, but plenty at 1500 RPM or more.  SInce the engine is not really trying to make power at idle, it only takes enough oil flow to keep the bearings flooded.

    When you hear lifters clattering, then you can start worrying.

    IF it really bugs you, use higher viscosity oil on your next oil change to see if it helps..

    Money you enjoy wasting is NOT wasted money... unless your wife finds out.
     

     

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