Need help please

[chevygirl77]

My 2000 gmc lost all oil pressure I replaced the oil pump and the sending unit part and still have zero pressure ??

Please someone help I am stumped??

[txab]

Have you checked pressure with a mechanical gauge? Does the engine knock?

[Ramin258]

1. I assume you have checked the dip stick and verified your oil level.

2. Do you have an oil light that is lit on your instrument cluster?

3. With the truck on level ground check the oil level on the dip stick (pull it, wipe it, then check it) after the truck has been off for awhile (10-20 minutes). Visually note where the oil level is on the dip stick. Now wipe the dip stick clean again and put it back. Start the truck, run it for 30 seconds and shut it off. Immediately go and check the dip stick again (pull it, wipe it, then check it), the oil level on the dip stick should be noticeably lower if you are picking up oil with the pump and it is going through the top end of the motor. If the oil level does not go down you know the motor is not getting oil.

4. Check all electrical connections from sending unit to gauge

[iCryWheniGoPoop]

Several possibilities,

 

First... do not trust oil light, electric gauge. do like another poster suggested and get a mechanical test gauge and verify no pressure.

 

If you have verified no pressure with know working mechanical gauge then there are several things it could be.

Low oil,

bad pump,

clogged pickup screen

Pickup tube fell out or has come loose

damaged filter

lost an oil galley plug (rare but has happened)

 

If motor still runs without knocking then you will have some oil pressure.

[chevygirl77]

Have you checked pressure with a mechanical gauge? Does the engine knock?

 

Several possibilities,

 

First... do not trust oil light, electric gauge. do like another poster suggested and get a mechanical test gauge and verify no pressure.

 

If you have verified no pressure with know working mechanical gauge then there are several things it could be.

Low oil,

bad pump,

clogged pickup screen

Pickup tube fell out or has come loose

damaged filter

lost an oil galley plug (rare but has happened)

 

If motor still runs without knocking then you will have some oil pressure.

 

Several possibilities,

 

First... do not trust oil light, electric gauge. do like another poster suggested and get a mechanical test gauge and verify no pressure.

 

If you have verified no pressure with know working mechanical gauge then there are several things it could be.

Low oil,

bad pump,

clogged pickup screen

Pickup tube fell out or has come loose

damaged filter

lost an oil galley plug (rare but has happened)

 

If motor still runs without knocking then you will have some oil pressure.

 

Several possibilities,

 

First... do not trust oil light, electric gauge. do like another poster suggested and get a mechanical test gauge and verify no pressure.

 

If you have verified no pressure with know working mechanical gauge then there are several things it could be.

Low oil,

bad pump,

clogged pickup screen

Pickup tube fell out or has come loose

damaged filter

lost an oil galley plug (rare but has happened)

 

If motor still runs without knocking then you will have some oil pressure.

 

Several possibilities,

 

First... do not trust oil light, electric gauge. do like another poster suggested and get a mechanical test gauge and verify no pressure.

 

If you have verified no pressure with know working mechanical gauge then there are several things it could be.

Low oil,

bad pump,

clogged pickup screen

Pickup tube fell out or has come loose

damaged filter

lost an oil galley plug (rare but has happened)

 

If motor still runs without knocking then you will have some oil pressure.

There is a knocking to the motor,my guage has zero pressure

[chevygirl77]

Have you checked pressure with a mechanical gauge? Does the engine knock?

I will have to get a mechanical gauge,yes it does knock..

I have bought new pump and pressure sending unit and have done a few oil changes to see if things would change and it still has zero pressure

[chevygirl77]

1. I assume you have checked the dip stick and verified your oil level.

2. Do you have an oil light that is lit on your instrument cluster?

3. With the truck on level ground check the oil level on the dip stick (pull it, wipe it, then check it) after the truck has been off for awhile (10-20 minutes). Visually note where the oil level is on the dip stick. Now wipe the dip stick clean again and put it back. Start the truck, run it for 30 seconds and shut it off. Immediately go and check the dip stick again (pull it, wipe it, then check it), the oil level on the dip stick should be noticeably lower if you are picking up oil with the pump and it is going through the top end of the motor. If the oil level does not go down you know the motor is not getting oil.

4. Check all electrical connections from sending unit to gauge

I hane done this and the oil is staying where it has been full???

[Ramin258]

Sounds like the motor is truly not getting oil. Like stated above, your pick up screen could be clogged, pickup tube loose or came off.