Rear main seal install

[m.mcmillen]

@Capote I am trying to get my rear main seal installed on my engine and I'm having a bit of trouble. Did you use the plastic sleeve that came with the seal and slide it over the crankshaft and then remove the plastic after the seal is in?

I can't the the plastic piece to go over the crankshaft. I tried it without that and screwed up a seal.

The seal that I bought came installed in the new housing.

 

[mrrsm]

The White Plastic Seal Keeper designed to hold the Crankshaft Seal is there in order to keep out any contamination and keep the opposing sides of the PTFE Seal facing AWAY from each other prior to installation. What works best is to clean the Outer End Diameter of the Crankshaft with Lacquer Thinner in order to guarantee that the surface is clean and smooth and then lightly oil the end OD of the shaft with 3&1 Oil. Don't remove the Plastic Guide until the very last minute before doing the Seal installation... IT KEEPS THE INNER AND OUTER SEAL SLIGHTLY STRETCHED SO THAT SLIDING IT OVER THE OUTER DIAMETER OF THE CRANKSHAFT IS BOTH POSSIBLE AND PAINLESS,

The important thing to do is to sit on a chair at the back of the Block and if possible, use the Engine Hoist so that as you introduce the Back Plate and Seal on very slowly in order to prevent the Inner Lip from folding inwards upon itself and defeat its design. This can be accomplished better if the Engine Hoist is used to lift and hold the Engine and then lower the Block down onto a large, assembled cardboard box with just enough contact to keep it from swinging around while you are seated at the back of the Engine and looking directly at the very end of the Crankshaft.

The Engine Mount Pivot should be removed to give you some 'Elbow Room'. After that you will have to be careful and gentle so you can manoeuvre the Back Plate and Seal over the Crankshaft just a little at a time... because you have to be mindful of the Two Alignment Pins in the back of the Engine Block for the Back Plate to slip over. If you get too hectic while handling the Back Plate once the Seal begins to slide... it will come off very easily...so when you observe the Outer Seal passing over the end of the Crankshaft STOP and install a few Back Plate Bolts and tighten them by hand uniformly and with enough threads to keep the Seal Centred on the back of the OD of the Crankshaft. Once both the Inner and Outer Sealing Edges have cleared... install all of the Bolts and tighten according to the Manual. Of course you should apply the GM AC-Delco Engine RTV on the Flange of the Back Plate and plan to get ALL of this accomplished with 15 Minutes as that will be your Total Working Time for the RTV Sealant.

 

[m.mcmillen]

Right, I bought a large tube of the AC Delco sealant that goes in a caulk gun. I'm using quite a bit of it lately.

I did what you said the first time I tried and the seal seems really tight to me. The reason I mention the sleeve is this excerpt from the manual :
Important: When installing a new seal, use the plastic installation sleeve supplied with the new seal.
The seal installation sleeve should come off after the seal is installed. Disregard the sleeve.

I'll give it another go tomorrow and see what happens.

 

[Mounce]

For some reason I feel like I heard there were two different seal sizes on these. I guess varied by year?

 

[mrrsm]

In a like manner to your own recent experience... I found the White Plastic Seal Holder more of an impediment to the installation than any help. So I studied the direction of the Inner Seal Lip and after removing the White Plastic Item... I Cleaned and Lubed the end of the Crankshaft and used a small amount of 3&1 Oil on my Index Finger to VERY SLOWLY AND VERY GRADUALLY EXPAND THE LEADING EDGE OF THE INNER SEAL so that it would slide over the OD of the Crankshaft. Since the Outer Seal Lip faces Outwards... it will behave itself as the Seal is being guided on. It is the Inner Seal that poses the greatest difficulty.

Please know that when I was doing this job... I was sitting underneath the elevated SUV on Jack Stands in the vacant space where the 4L60E Transmission would be ...so I had a Bird's Eye View of the end of the Crankshaft ...and in my installation... it was not necessary to remove and replace the Rear Back Cover. I used a small block of 2"X4" Pine Wood and a small Ball Peen Hammer... and once I managed to clear the entry points for the edges of BOTH the Inner and Outer Seal, I followed a repeating tapping pattern or sequence if you prefer of 12-6, 3-9, 1-7, 10-4 to gradually allow the multiple fine rubber ribs to be driven in so that the entire Seal went home flat and even with the circular back of the Engine Block. Too much haste here has a tendency to cause one or another side to actually pop right back out of the sealing location in the Block.

The are only a few things that can break down the very reliable performance of a PTFE Engine Seal. These include being either cut or sliced by a sharp instrument or a scuffed or nicked when in direct, continuous contact with a damaged bearing surface. Beyond that... The Technical White paper Literature describes a problem of "Gravitational Sagging" which normally happens in ALL applications of this sealing material after around 185,000 Miles. The long and the short of it is though... That if the Seals are installed with Great Care... they really do a great job of keeping Oil inside of an Engine... and while preventing leaks... they very well manage to keep the Hostile Elements of Dirt and Water outside where they can do no harm.

 

[m.mcmillen]

For some reason I feel like I heard there were two different seal sizes on these. I guess varied by year?

I think you might be thinking about the front seal. I saw that there are a couple of different options there.

I called the dealer and they said that the same rear seal was used from 2002-2007.

 

[mrrsm]

This is Very Important:

I've been thinking about something that @littleblazer mentioned above concerning a circumstance where a Flex-Plate Failed under such circumstances involving it detonating with such violence as to damned near cut a vehicle half in two. Given the dreadful condition of how @Capote 's Flex-Plate turned out to be and to @littleblazer 's observation... it seems terribly important to take this idea under advisement before considering to Start Up The Engine after the Torque Converter Bolts, the Transmission and the Torque Converter have all been removed.

There would be a very real danger in starting and running the engine at all; let alone suddenly raising and lowering the RPM while the Flex-Plate is only being held just by the (8) Bolts in the centre where the cracked areas won't be easy to see or detect... just under the Stainless Steel Thrust Washer under the (8) Bolts. If something untoward were to occur... there is no telling whether or not the Plate itself might break loose and Fly off of the Tail of the Crankshaft and wreak havoc towards anyone standing near or laying under the vehicle.

I remembered this Youtube Video was being done to investigate the strange "Bell Ringing" sound which appears to be the familiar, redoubtable sound that a Broken Flex-Plate can make if cracked in one or more of the 'Kidney Bean' Cut-Outs leading back to its centre. And so of course...this would be the very last place you would want to be standing near to... or lying under... should the Flex-Plate suddenly come apart without the Torque Converter Bolts and Torque Converter present to restrain it in place and not fly around in that vacant space at high speed like some Deadly Toothed Demon Frisbee:

 

[Capote]

There's one size for the rear and one size for the front.