97 lumina oil pump
jhelpy
11-21-2006, 08:14 AM
how do i change the oil pump on a 97 lumina with a 3.1. the oil light came on while driving down the road and the oil pressure disappeared.
Blue Bowtie
11-21-2006, 10:59 AM
Welcome Aboard!
The first thing to determine is whether the oil pressure has actually dropped, or if the gauge/light sensor has simply failed. Connecting a mechanical oil pressure test gauge will show the actual pressure, and whether the in-dash gauge/light are displaying correctly.
If the oil pressure is actually low, you also need to investigate the oil in the sump. Type of oil being used and whether it is contaminated with fuel or other substances can greatly affect oil pressure. Multi-viscosity mineral oil which is broken down (exhausted all the fortifying polymers) will also result in lower pressure.
If the actual oil pressure is low while using clean, fresh oil in the correct viscosity range, and with the correct oil filter, you MAY have an oil pump problem. There may also be clearance problems with bearings, or it may be as little as a low-quality oil filter which is not allowing sufficient flow (high pressure differential and poor bypass design).
If the oil pressure is adequate with the test gauge, you need to investigate the dash gauge and pressure transducer on the engine.
Before you get all excited about raising the engine and removing the oil pan to bolt on a new pump, perform some diagnosis. Oil pumps rarely go bad.
The first thing to determine is whether the oil pressure has actually dropped, or if the gauge/light sensor has simply failed. Connecting a mechanical oil pressure test gauge will show the actual pressure, and whether the in-dash gauge/light are displaying correctly.
If the oil pressure is actually low, you also need to investigate the oil in the sump. Type of oil being used and whether it is contaminated with fuel or other substances can greatly affect oil pressure. Multi-viscosity mineral oil which is broken down (exhausted all the fortifying polymers) will also result in lower pressure.
If the actual oil pressure is low while using clean, fresh oil in the correct viscosity range, and with the correct oil filter, you MAY have an oil pump problem. There may also be clearance problems with bearings, or it may be as little as a low-quality oil filter which is not allowing sufficient flow (high pressure differential and poor bypass design).
If the oil pressure is adequate with the test gauge, you need to investigate the dash gauge and pressure transducer on the engine.
Before you get all excited about raising the engine and removing the oil pan to bolt on a new pump, perform some diagnosis. Oil pumps rarely go bad.
richtazz
11-21-2006, 01:22 PM
I agree with Blue. Unless the engine started making bad noises and getting hot when the oil pressure disappeared, I doubt it's an oil pump. You'd have seized the engine if you drove it more than a few hundred yards with a failed oil pump. You need to check for contaminants such as coolant in the oil, as you could have other issues that caused the light to come on. As Blue suggested, it would be wise to change the oil and filter to eliminate the oil itself as a contributing factor. The oil pressure switch/sensor is mounted just above the oil filter on the front of the engine, so it's very possible it came disconnected. Try the simple stuff before you rip an engine apart. Besides, if the oil pump is the problem, and you drove it very far afterward, the bearings are probably toast anyway.
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