gerotor vane type.


Engine lubrication is supplied by a gerotor type oil pump assembly. The oil pump is mounted on the front of the engine block and driven directly by the crankshaft sprocket. The pump gears rotate and draw oil from the oil pan sump through a pick-up screen and pipe. The oil is pressurized as it passes through the pump and is sent through the engine block lower oil gallery. Contained within the oil pump assembly is a pressure relief valve that maintains oil pressure within a specified range.

Pressurized oil is directed through the engine block lower oil gallery to the full flow oil filter where harmful contaminants are removed. A bypass valve is incorporated into the oil filter, which permits oil flow in the event the filter becomes restricted. A second valve, the active fuel management oil pressure relief valve is incorporated into the oil pan. The active fuel management oil pressure relief valve limits oil pressure directed to the upper oil galleries and oil manifold assembly to 379-517 kPa (55-75 psi) maximum.

Oil is then directed from the filter to the upper main oil galleries and the valve lifter oil manifold assembly. Oil from the left upper oil gallery is directed to the crankshaft and camshaft bearings. Oil that has entered both the upper main oil galleries also pressurizes the valve lifter assemblies and is then pumped through the pushrods to lubricate the valve rocker arms and valve stems.

An oil passage at camshaft bearing location 2 permits oil flow into the center of the camshaft. Oil enters the camshaft exiting at the front and into the camshaft position (CMP) actuator solenoid valve. The CMP valve spool position is controlled by the engine control module (ECM) and CMP magnet. When commanded by the ECM, the CMP magnet repositions the CMP actuator solenoid valve spool directing pressurized oil into the CMP actuator to control valve timing. Refer to Camshaft Actuator System Description (See: Powertrain Management\Computers and Control Systems\Description and Operation\Camshaft Actuator System Description).

Oil returning to the pan is directed by the crankshaft oil deflector. The oil pressure sensor is located at the top rear of the engine. For RPO L99, active fuel management hardware is present in first design engines. Refer to Cylinder Deactivation (Active Fuel Management) System Description (See: Description and Operation\Cylinder Deactivation (Active Fuel Management) System Description) and Camshaft Position Actuator and Solenoid Valve Description (See: Camshaft\Description and Operation).

 

another description.....

Lubrication System Description

Engine lubrication is supplied by a variable displacement vane-type oil pump assembly. The oil pump is mounted on the front of the engine block and driven directly by the crankshaft sprocket. The pump rotor and vanes rotate and draw oil from the oil pan sump through a pick-up screen and pipe. The oil is pressurized as it passes through the pump and is sent through the engine block lower oil gallery.

Pressurized oil is directed through the engine block lower oil gallery to the full flow oil filter where harmful contaminants are removed. A bypass valve is incorporated into the oil filter, which permits oil flow in the event the filter becomes restricted. The active fuel management oil pressure relief valve limits oil pressure directed to the upper oil galleries and valve lifter oil manifold assembly to 379-517 kPa (55-75 psi) maximum. When main oil pressure exceeds 379 kPa (55 psi), the oil pressure relief valve exhausts excess oil to the sump.

Oil is then directed from the filter to the upper main oil galleries and the valve lifter oil manifold assembly. Oil from the left upper oil gallery is directed to the crankshaft and camshaft bearings. Oil that has entered both the upper main oil galleries also pressurizes the valve lifter assemblies and is then pumped through the pushrods to lubricate the valve rocker arms and valve stems. Oil returning to the pan is directed by the crankshaft oil deflector. The oil pressure sensor is located at the top rear of the engine.

An oil passage at camshaft bearing location 2 permits oil flow into the center of the camshaft. Oil enters the camshaft exiting at the front and into the camshaft position (CMP) actuator solenoid valve. The CMP valve spool position is controlled by the engine control module (ECM) and CMP magnet. When commanded by the ECM, the CMP magnet repositions the CMP actuator solenoid valve spool directing pressurized oil into the CMP actuator to control valve timing. Refer to Camshaft Position Actuator and Solenoid Valve Description (See: Camshaft\Description and Operation) and Camshaft Actuator System Description (See: Powertrain Management\Computers and Control Systems\Description and Operation\Camshaft Actuator System Description).

With active fuel management activated, the ECM commands the 4 valve lifter oil manifold solenoids to open, directing oil through the engine block oil galleries to the intake and exhaust valve lifters for cylinders 1, 4, 6, and 7. With active fuel management activated, cylinders 1, 4, 6, and 7 are disabled.

 

Evios Thanks for the information, First Class you are the book of knowledge.

 

I was wondering......if most engine wear occurs during cold start ups, probably hot start take a toll on engine wear parts as well. (bearings and else).

Why Our cars don't have a prelube pump or system to be applied on the auto-stop to engine on transition ? I know synthetics have come a long way, still some grade of wear must be achieve during this operation!

Could be electrical o pressurize one, that zips just a sec before the Engine on mode....

Just my Yoga thoughts !!!!

 

like a dry sump lubrication?

 

Well, that will be sweet, but I mean more for dry start up situations.............

I have a 69 Camaro SS, and in the old 355ci I used an AMSoil Precharger. Just recently took the engine out for a LSX454 swap, and the old 355 is like new.....and I pounded every time I drove it !

Have not yet install the new LSX454, but I pretend to reuse the AMSoiler cause it went great.

When I first got my hybrid, I thought it have some system like that....but then I learn other wise.

Could be a nice addition for the newer fleet!

 

I think the bearings are still wet for a while after the engine is off, so for the short times the engine is in autostop, it should be less of an issue, but pre-oiling would be great, unfortunately, not practical. When the Hybrid Control Module knows it is time to start the engine, the added delay of turning on a pre-lube system and waiting for oil to flow would create a bad driving experience. Now, having the pump running during autostop would keep oil pressure up, but also waste power. This would also require an electrically driven oil pump, which is less efficient always and is less reliable.

 

They will be kind of wet comparing to a dry start, still no acceptable lub imo. Autostop has rules of his own, depending a lot if all accessories are on, if u are using the power to move, or just in idle. If the Lub system was a dry sump, that will help a lot for the starts, but is a regular wet sum, meaning once oil pump stops, all the oil goes to the carter per gravity.

My AMSoiler has an electric pump, Georotor type I think, and has been reliable for some years now, but the Maro is not a daily driver, so cant swear for longevity under hardcore use.

Trying to desing the system I'll will ask the pump to push just a few seconds before the Schedule next Start, just 50% power prime, cause as u stated, bearings will be "kind of wet". For the Blending I'm totally sure it can be done, as with the AFM working time rates. Will waste some power, but not like it will drain the battery pack. An as the AFM have to be stealth type working ! GM engineers rulessss

 

With todays oils I think the only issue maybe a vehicle sitting in the cold weather for a long period of time say a month before the lubrication has run off. As far as Auto-Stop this is not an issue we are only turning 2,000 - 4,000 rpms and the engine has already warmed up before this occurs. Cold weather tests on Radial Engines in the 40's revealed that pre-oiling an engine at zero degrees was a good idea, again this is heaver oil with larger bearings. Today I think this form of engine wear is min. synthetic oil is all that much better, best medicine here for your engine CLEAN OIL and Filter regularly.

 

My problem: 2 weeks ago my dealership had to do some rewiring to resolve a screen flicker in my dvd system. They mentioned that the circuit was related to the electronic brake system, which I thought was unusual. I was a wrench bender 20 years ago and these rolling computers scare me now. But anyway...

After getting the truck back from the dealership, I completed a conversion to remove the resonator and install a spare tire in it's place (not a fan of the run-flat concept). When discussing this project with my repair advisor, I was told it could effect the engine because of the back-pressure, but I read on this forum that others have removed the resonator with no ill effects.

Following the work done.. after driving for 30 minutes with good oil pressure, parking for about an hour and then re-starting, I get no oil pressure and the warning message. Turn ignition off and on again and the pressure is normal. I'm used to oil pumps being purely mechanical, but now I'm thinking my problem may be related to the ECM. Last night after driving to the gym, working out and then starting the truck back up, I had no oil pressure. Ignition on/off/on didn't fix the issue. Had it towed to the dealership. They heard the valve tap upon starting this morning, but the pressure came up. Dern grimlins.

2009 Yukon Hybrid.