The Front and Rear Crankshaft Seals are made of PTFE (Poly-Tetra-Fluoro-Ethylene)...Literally...
Teflon. Unfortunately, unlike the
Black Natural Latex Rubber Seals of Old that would often "Plump Up" after being soaked in Used Motor Oil
as rightly suggested by @BrianF... there are very few if any Oils or Grease that can actually 'stick tight' enough to its Ultra-Slick, Microscopic Brown or Blue
Teflon Surfaces to actually work to close up any Lost Sealing Gaps or leaking areas. The Failure Modes of
Teflon Seals take the following paths:
(1) Cuts to the PTFE Sealing Material or Impact Damage to the Outer Seal Housing.
(2) Improper Installation from Excessive Pounding Impacts that will cause the Coil Spring Expander to become completely dislodged from inside of its casement. This unfortunate event completely removes every bit of the necessary "Squeeze" required to maintain enough pressure on the
Teflon Material to keep it in constant contact with the rotational surface around the smooth OD of the Crankshaft,
(3) Direct Damage to the Outside Diameter of the Crankshaft that presents with nicks or sharps in contact with the Seal as the Crank spins around.
(4) Gravity.
Yes... As strange as this might sound...
ALL PTFE Seals will begin to stretch and "sag" enough merely from Gravity over time' enough in fact to leave a substantial gap forming around the bottom areas of these
Teflon Seals. This usually happens at around 185,000 Miles of use and wear (According to the White Paper on the use of Teflon in Seals). So the very act of simply sitting there... unused will also take its toll on these seals over time.
(5) Direct Exposure to Extremely Powerful Solvents and Gases that involve highly corrosive compounds containing exotic combinations of Hydrogen and Fluorine.
The only real help for this situation is to R&R the Harmonic Balancer, Pry Out the Old Seal ...and using a Small Block of Wood in between...Lightly Tap a Brand New Seal right back into the Front Timing Cover until the Casement is flush with the front face of the area.
No Oils or Sealants need to be applied, lest they get trapped within the Sealing Groove and Spring areas of the New
Teflon Seal. These lubricants may actually shorten the life of
Teflon Seals by attracting and holding Abrasive Sand, Dirt and Grit inside of those narrow areas and eat into the OD of the Rotating Metal Surfaces.
The Front Crankshaft Fastener is a Large, "Use Once and Throw it Away..." TTY Bolt. So replacing-installing a New One after restricting the movement of the Flex-Plate at one of the Torque Convert Bolts is required. This can be done by using 15mm Impact Socket and a 1/2" Breaker Bar underneath the Engine to Transmission areas. Access to any One of the Three Torque Converter Bolt is made through a small passageway covered by a
Small, Black Plastic Plug located in the underside of the Back Plane of the Crankcase-Oil Pan.
The Brand New $10.00
TTY Crankshaft Bolt required here is threaded into the Nose of the Crankshaft after a
New Harmonic Balancer Special Friction Washer is fitted to the Inner Snout of the HB Bore. During the First Turning Pass... That Bolt gets Tightened to 110 Foot Pounds. Then, after making a Visible Mark in White using a Permanent Oil Ink Pen... A Vertical Line gets drawn across the TTY Bolt Face and onto the Timing Chain Cover.
Then using that White Line as a ready reference, that TTY Bolt gets slowly turned another 180 Degrees, starting at the 12:00 Position... and ending up at the 6;00 Position. The Harmonic Balancer(s) of all GM Atlas 4,5 & 6 Cylinder In-Line Engines Do NOT have Woodruff Keys necessary to prevent the HBs from rotating separately from the ODs of the Crankshafts while being Tightened. So the Crankshaft MUST be restricted from turning during these TTY Torque Procedures, or you'll run the risk a having failure with the Harmonic Balancer Friction Washer Seals during these efforts to firmly fasten everything together.
Depending upon which year GM Atlas Engine is being worked on for this Repair (2002-2003 Require a Special Puller) the Later Model Years can use the OEM Brand Model #6667 Puller to remove the updated Harmonic Balancers available on Amazon. For around $15.00- $20.00... There is a Special Hardened Threaded Rod with a Nut and several Special Washers in a Kit also offered on Amazon that can be used in combination to properly re-install ALL versions of these Harmonic Balancer(s). Just remember to wipe the Bolt Threads down with some High Pressure Grease to make this part of the job a LOT EZR.