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Unread 07-01-2013, 02:16 PM   #1
dirtdad
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flickering oil light at idle

Never happen before. Sometimes at idle the oil light will flicker. As soon as I come off idle, it goes out. Never actually lights brightly, just kind of glows. Any ideas? Should I try a thicker oil?

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Unread 07-01-2013, 07:36 PM   #2
AZ Jeff
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Start by measuring oil pressure with a mechanical guage installed where the oil light switch is located. Minimum oil pressure at idle is 13psi.

If that shows to be OK, then buy a new oil pressure light sender.
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Unread 07-02-2013, 01:39 PM   #3
CitadelXJ
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Why does everyone think thicker oil is the answer? I've got friends that are running something like 20W-40 or something like that and wonder why they go through oil pumps every couple years.
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Unread 07-02-2013, 01:55 PM   #4
mschi772
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Quote:
Originally Posted by CitadelXJ
Why does everyone think thicker oil is the answer? I've got friends that are running something like 20W-40 or something like that and wonder why they go through oil pumps every couple years.
Because they want to believe in a quick and easy solution. Oil is a complicated subject anyway hence the existence of (super informative) sites like Bob Is the Oil Guy.

OP, I concur with the above recommendations to check with a mech gauge. The fault may simply lie with your current sensor.
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Unread 07-02-2013, 02:49 PM   #5
Carl48
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Use the API approved oil the manufacturer recommends and disregard anything else you hear about oil, additives, etc.

Check the oil pressure with a mechanical guage as has been mentioned before coming to any premature conclusion.
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Unread 07-02-2013, 06:46 PM   #6
tjwalker
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Yup, verify with a mechanical gauge.

I knew a guy who actually rebuilt his engine when the only issue was a faulty oil pressure sending unit.

Data, data, data....
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Unread 07-02-2013, 09:16 PM   #7
BIGBADWOLF
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Quote:
Originally Posted by CitadelXJ View Post
Why does everyone think thicker oil is the answer? I've got friends that are running something like 20W-40 or something like that and wonder why they go through oil pumps every couple years.
Because they think backwards:
Low oil pressure is not necessarily bad. In fact, it can be beneficial to a engine operatiing within normal limits.
By the same token, high oil pressure is not necessarily good. It can be caused by blocked oil galleries or a too viscous (thick)lubricant.

Oil pressure is caused by the oil's resistance to flow. Therefore, wide oil clearances and low oil viscosity permit oil to flow freely.
The results would be low oil pressure and more reliable lubrication. Conversely, narrow oil clearances (either by design or
blockage) and high oil viscosity causes lower oil flow. While oil pressure would be high, lubrication would not be as efficient. A
"good" oil, therefore, has viscosity characteristics sufficient to provide good hydrodynamic lubrication and also flows freely
around the engine to maintain a continuous supply of lubricant.
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