No OIL pressure on 1966 flh

Discussion in 'General Harley Davidson Topic' started by MGRUMPY1, May 16, 2013.

  1. MGRUMPY1

    MGRUMPY1 New Member

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    Hello All, I have a problem I cant figure out. I have little to no oil pressure after the engine is warmed up. At start up I have about 30 psi at the oil pump and at rev I have up to 60 psi. Once I ride it about 3-4 miles its drops off and then the clattering starts. I have replaced the oil to 70W and I also replaced the side oil pump spring to a stiffer spring. I cleaned out the tappet screen and replaced the oil filter too. I installed a reducer on the up tube to the rear head with a .063 jet. I have not had the oil pump off nor have I gone into the cam cover or any of the tappets. This is a new problem to me but so is this bike. Any and all help would be greatly appreciated. Thank you.
     
  2. BUBBIE

    BUBBIE Well-Known Member

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    No Post yet?

    I would think since it shows pressure when cold, and dropping when hot. I'd suspect the oil pump.

    I had an EVO bought new in 1997 was the model year but too new and never had the pump out. But I'd lean that way. Cold oil fits tight into the oil gears and Hot,,,gears are too loose and oil is nada.:(

    signed....BUBBIE
     
  3. Jack Klarich

    Jack Klarich Expert Member

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    The way these old oiling systems work, I would pull the pump first and check for worn gears and missing keys, pay particular attention to the height of the gears to the pump body
     
  4. SledDog

    SledDog Senior Member Staff Member Moderator

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    The issue may be the 70wt. You are trading viscosity for flow. You may have miss adjusted pushrods, or a bad lifter. That's not a good thing at times.

    When was the last time the top end was rebuilt? That vintage needs one about every 20,000 miles.

    Why reduce the flow in the tube? You are starving the rear jug for oil. 60 psi is not a good thing for the motor.

    You need to do the basic check. Make sure your push rods and lifters are adjusted correctly. That could be some of your problem.

    If I were you, I would remove the .063 jet from the oil tube ASAP.

    It's not unusual for the psi on that motor to be 2 or 3 psi at idle when hot. That why flow is more important than viscosity.
     
  5. MGRUMPY1

    MGRUMPY1 New Member

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    I still have low pressure. I adjusted the push rods but I might have done it wrong. Can any one give me step by step instructions on how to correctly adjust them? I have read/saw about 5 different ways to do it. Which is best?
     
  6. tourbox

    tourbox Senior Member

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    Do you have stock lifters & push rods.? Are the lifters Hydraulic or solids, or converted to solids from hyd. with cups?
    tourbox
     
  7. Jack Klarich

    Jack Klarich Expert Member

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    Per the manual, with the valve to be adjusted at the lowest spot on the cam adjust the push rod til all shake is gone on push rod, then turn 4 full turns, 24 flats and jam nuts tight, wait for lifter to bleed down, Check the tappets before adjusting, remove them 1 at a time, hold it in your hand and pump down on plunger and hold for 6 seconds, release it and it should respond back, if it does not replace it before adjusting push rod
     
  8. tourbox

    tourbox Senior Member

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    The plunger(lifter itself) has a ball check valve in it. You should be able to hear it rattle around by shaking it after cleaning. I usually clean them with Lacquer thinner. Let them soak a few minutes or more. Jack has you covered on adjustment. I agree with SledDog about removing your restriction in the oiling line for you Rocker Boxes. These old Pans & Shovels didn't have a lot of oil pressure at idle once warmed. I believe the switch is a 5-7 psi to keep light out. Once warm, running down the road at 2k plus rpm maybe 25 psi. There is an easy check for flow after start up.
    tourbox
     
  9. panhead_jim

    panhead_jim Member

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    Couple questions:

    Is your oil pressure light coming on?

    Have you verified that oil is making it back to your oil tank while the bike is running?