Oil pump
12-07-2011, 05:25 PM
#1
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Oil pump
Hello,
I'm wondering if my LT1 needs a new oil pump. My oil pressure gauge reads about 45 at cold idle, and 50 at cold driving. When at 180*, the idle pressure drops to about 15. Warm driving is about 40. My gauge doesn't bounce all around at idle so I believe my gauge is ok. My engine has about 140k on it.
Thoughts?
I'm wondering if my LT1 needs a new oil pump. My oil pressure gauge reads about 45 at cold idle, and 50 at cold driving. When at 180*, the idle pressure drops to about 15. Warm driving is about 40. My gauge doesn't bounce all around at idle so I believe my gauge is ok. My engine has about 140k on it.
Thoughts?
12-07-2011, 05:46 PM
#3
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12-07-2011, 07:46 PM
#9
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Re: Oil pump
I thought that loss of oil pressure was caused by increased tolerances from bearing wear. It is my understanding that oil pumps rarely fail and cause a low oil pressure condition.
Maybe someone can clarify?
Maybe someone can clarify?
12-07-2011, 07:59 PM
#10
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Re: Oil pump
Also remember that the oil's viscosity raises as it becomes hotter
12-07-2011, 10:37 PM
#11
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Re: Oil pump
Viscosity drops as oil heats up. Its thick when its cold, thin when its hot.
From the Exxon/Mobil website:
Mobil 1 5W-30
SAE Grade 5W-30
Viscosity @ 100ºC, cSt (ASTM D445) 11.0
Viscosity, @ 40ºC, cSt (ASTM D445) 61.7
From the Exxon/Mobil website:
Mobil 1 5W-30
SAE Grade 5W-30
Viscosity @ 100ºC, cSt (ASTM D445) 11.0
Viscosity, @ 40ºC, cSt (ASTM D445) 61.7
12-07-2011, 11:09 PM
#12
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Re: Oil pump
Presumed loss of oil pressure can come from an old sensor. They often indicate lower pressures as they age and as they get hot.
12-09-2011, 10:39 AM
#14
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Location: Metro Detroit, MI
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Re: Oil pump
I often hear a lot of people talk about replacing pumps but being mechanical gear driven pumps I don't see how they can go bad so easily.
I spun a rod bearing so I disassembled the pump to clean out any shavings that may be in there, and replaced the nylon with a steel sleeve.
My oil pressure has been fine, although I will mention that my nylon sleeve was broken when I dropped the oil pan.
I've read that the sleeve breaking is common and can result in a slight loss of pressure but I am not sure how true that is.
I spun a rod bearing so I disassembled the pump to clean out any shavings that may be in there, and replaced the nylon with a steel sleeve.
My oil pressure has been fine, although I will mention that my nylon sleeve was broken when I dropped the oil pan.
I've read that the sleeve breaking is common and can result in a slight loss of pressure but I am not sure how true that is.
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