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Low Oil Pressure

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Old 05-06-2009, 02:15 PM
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Default Low Oil Pressure

Hey guys, I just recently took my blazer out of storage and the first thing I did was change the oil, I was close to needing one done so I decided to just do it...I replaced the Oil filter got some new oil in it. However, my oil pressure, when at operating temp and idling, drops down to 0. Every time I step on the gas it jumps back up to 30, but when I stop it drops down to 0....Any possible solutions? Its a 1992 k5 with almost 184k miles on it, its a 5.7L 350.
 
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Old 05-06-2009, 02:37 PM
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Have you verified actual oil pressure with a manual gauge? That'll everybody's first question.
 
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Old 05-06-2009, 03:25 PM
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1st question I would ask!
 
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Old 05-06-2009, 08:00 PM
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No, I havent...How would one go about doing something like that?
 
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Old 05-06-2009, 08:11 PM
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Disconnect the stock oil pressure sending unit and plumb in a mechanical gauge. If you put a 'T' in the line, you can leave the mechanical gauge in for future verification.

If the mechanical gauge reads low at idle, then you may have a weak pump. Or you have a problem with bearing clearances possibly allowing pressure to bleed off before it gets to the top end of the motor.

I would suspect a bad sending unit though.
 
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Old 05-08-2009, 09:36 AM
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Ok...still new at the whole do it yourself thing...I need help locating the oil pressure sending unit, any help would be greatly appreciated.
 
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Old 05-08-2009, 10:36 AM
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Back rail on the engine block to the driver side of the distributor.
 
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Old 05-08-2009, 11:15 AM
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Ok, thanks for the help, Its raining right now, but once it stops I'll go check it out.
 
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Old 06-11-2009, 10:06 PM
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i have preaty much the same thing with the same problem i had moboil in it and it got worse sounded like valve train in front right was ticking real bad. i changed the oil to slightly thicker synthetic valvoline and it stopped hammering but oil pressure gauge will read o and check gauges comes on.
 
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Old 09-24-2009, 01:43 PM
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i have a 74 K5 that is leaking oil from under the dash can anyone help
 

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