Five Part Video Series on GM 4.2L Oil Pick-Up Tube R&R

[mrrsm]

Kevin Nadeau’s relatively new, informative, instructive and entertaining video work on Youtube regarding his GMC Envoy 4.2L Engine Oil Pick Up Tube Repair is worth viewing and downloading. Each and every time you can get to do the rare peek over someone’s shoulder and take a look at either some or all of their work (...and honest mistakes) in progress on this engine ...will seriously improve your understanding and motivation when the time comes for you to get dirty and do your own repairs and replacement jobs on the GMT360 I-6 Engines. If Kevin is not presently a Member here at GMT Nation... He certainly deserves to be one:

Part 1

Part II

Part III

Part IV

Part V

 

[mrrsm]

And what would it have cost at the Dealership....?

 

[EPfiffner]

I enjoyed his video series also, impressive undertaking and lots of useful info. I actually commented on one of the videos about how rust free his Envoy is.

 

[Kurb]

Great videos for sure! I am hoping the years of frequent synthetic oil changes will prevent this from happening, but I have more miles than him, so I am wondering if low oil pressure is in my future.

 

[mrrsm]

I recently reviewed my original 2002 disassembly images when I first removed the engine head... and I noticed that there were these black rubbery looking semi circles that appeared to be like valve seals of some kind laying within each cylinder on the piston tops.

But upon reflection... I realized that these were actually Carbon Deposits that had broken free from the orbits around the valve seats in the Head... and they had fallen down on top of the pistons during the time when I was hammering on a sacrificial H-10 Hex adapter with a Ball Peen Hammer trying to loosen the 14 Major Head Bolts in the Aluminum Block and hope to avoid snapping them off. That did not work...BTW.

The more I think about why these engines seem to last for over 200,000 Miles and then fail... the more I believe that it is Carbon Deposits and unburned gasses that bypass the stuck, gummed up - carboned up Compression rings that presage the Engine failures. Think about it... The Gerotor Oil Pump in these motors can almost never wear out... so as long as there is sufficient fresh Mobil1 in the Crankcase and the Pressure Relief Valve mechanism does not get stuck inside the Pump...and as long as the Oil Pickup Tube fasteners and Gasket are intact enough to prevent any loss of Pump suction... there should be sufficient Oil Pressure to keep the rotating assembly well lubricated... Ad Infinatum.

So perhaps what is called for here are more regular de-carbonizing treatments with either ACDelco Top Engine Cleaner or BG 44 or Berryman’s and less of that crap will be able to bypass the rings... mix with old Oil... and form the chunky sludge that clogged the VOP’s Oil Pickup Tube ... Oh.... I agree with @Kurd... that more frequent Oil Changes and Oil Filter Changes at 3,000 Miles should be done, too... no matter what anybody else says to the contrary. If Carbon Deposits are destined to build up inside the Motor Oil in the Crankcase... It is reasonable causality that the ‘junk and gunk’ build up will not be able to accumulate enough to do any harm... if nothing but Fresh Synthetic Motor Oil is perpetually circulating through the Engine.

 

[mrrsm]

This video argues for Regular, 3,000 Mile Oil Changes.... and also for the Flush and Removal of Built Up Carbon and Sludge. If you watch this attached video, you'll hear the VOP keep calling what are actually "Carbon Chunks" by the name of "Grit". What his extremely clever Carbon Removal Treatment does though, is to use Pure Kerosene while completely filling up the Crankcase... and then after Pulling the Fuel Pump Relay... he uses short, controlled Starter Motor bursts, turning his engine over this way to cycle all of the Fresh Kerosene in the Crankcase... throughout the entire engine.

Before trying out his technique ... it will be very important to remove the Old Oil Filter and install a Brand New Cheap One in order to trap all of those loosened "Grit" particles ...and avoid flushing that Carbon Crap that has built up and become trapped inside the Old Oil Filter right back up inside of the recesses deep inside of the motor. Make certain to pre-fill the New Cheap Oil Filter thoroughly ...Half Way upwith 1/2 Kerosene and the other 1/2 with Organic Motor Oil so as to prevent the Gerotor Oil Pump from suffering any cavitation at the start of this process due to the Low Viscosity of Kerosene.

Later... The True Test of whether or not this Technique works will NOT necessarily be what you find loose down inside of the Drained out Blackened Kerosene Flush Liquid at the bottom of the Oil Drain Collection Pan... but what is found to be trapped up inside of the Cheap Oil Filter that you can see by performing an Oil Filter Autopsy... after these procedures are completed.

Once the Kerosene is Topped Off in the Crankcase... all of places where Sludge has been building up for 100,000 Miles or more will be treated; The Crankcase...The Oil Galleries... The Oil Pump and The Bypass Valve... and The Top End...including the insides of the Delphi Cam Phaser and CPAS- Oil Channels ... Everything will get a good dose of Kerosene exposure... but NOT while the Engine is Running... therefore no damage from friction can occur to Engine Components and Rotating Assembly Bearings.

My recommendation would be to follow up this Kerosene Flush Procedure by removing the 1nce Used, Clean-Out Oil Filter and replace it with another inexpensive Oil Filter using 2 Minutes of Pre-Fill Time using inexpensive 30W Motor Oil. Then fill the well drained Crankcase with the same stuff. Again... Leave the Fuel Pump Relay OUT and turn over the motor using 15-30 Second Bursts in order to Prime the Oil Pump, the Oil Galleries and the Valve Train with the Fresh Organic Motor well prior to Starting the Engine after replacing the FPR.

Immediately after the engine fires up... allow it to Idle for around five minutes... Do Not Raise the engine RPM until it has the chance to warm up nicely and circulate the Fresh Organic Oil throughout the entire engine and flush out and mix with any residual Kerosene that did not flow down and out directly while draining the Engine Block. Afterwards, you can gradually raise and lower the Engine RPM a few times prior to shutting off the motor for the last little bit of flushing out the Kerosene residue. When you Drain the Kerosene...it should be Jet Black with Dissolved Gunk and Carbon Sludge. This needs to be responsibly disposed of along with the Old Oil as Used Kerosene is a Fire Hazard.

Finally... Change out the Kerosene contaminated Organic Oil and Cheap Oil Filter for the right amount of Mobil1 5W-30 Motor Oil and Perform a 2 Minute Pre-Fill of either a Mobil1 or K&M Oil Filter. Then Start the engine and let it idle, observing the Oil Pressure and engine responsiveness after it has the chance to warm up for around 5 Minutes... and take it for a Test Drive. When you get back home... throw some Cardboard under the engine area when parked and idling to check over everything for leaks... Happy Motoring! :>)