O-Ring on 3400?!

[Rootie524]

i bought a rear main seal from felpro for my 02 3400 and it included a 1/2 o-ring. i have no idea what it is for. the little piece of paper thats included with it says on v6 engines if the rear main bearing cap is removed, this o-ring must be replaced at the recessed oil groove in the block. i have no idea where such a thing is.

do i really need this? if so where the heck does it go?

[geoffinbc]

It is there. Under the rear main cap it seals the passage way that oil flows through in the main cap. If you only replaced the main seal and never removed the oil pan then don't concern yourself with it.

[Rootie524]

the cap was removed. never saw an old seal and have yet to find a place to put a new one. only recessed oil hole i found was significantly smaller than the supplied o-ring.

[SappySE107]

Pic? Is this only Gen 1 blocks because I don't recall an o ring under the rear main cap.

[pocket-rocket]

Pic? Is this only Gen 1 blocks because I don't recall an o ring under the rear main cap.

x2

[60dgrzbelow0]

This information is quoted from Tom Currao's arcane book, "How to Re-Build Your GM V-6 60* Engine" ...

Page 112 Photo Insert:

"Four types of Rear Main Seals in the 60 Degree V6, in chronological order:
1. Two Piece Rope-Type
2. Two Piece Lip-Type
3. 5mm One Piece Lip-Type
4. 10mm One Piece Lip-Type

If your engine was fitted with either of the first two seals, throw them out and use the 5mm One Piece Seal. The Ten mm Seal is used on all Large Journal Cranks and can be installed with the crankshaft in position."

And regarding the "O" Ring matter...

From page 113...an excerpt out of seven paragraphs on the install procedures...

"Some Early Blocks and all Late Model Blocks use an "O" Ring to seal the Rear Main Bearing Cap to the block to reduce oil leakage between the cap and the block. The "O" Ring should be installed without any sealer to prevent it from slipping out of position..."

The remaining information on the page deals with the abundance of caution needed when sort of pre-installing the cap in such a manner that prevents the slippage of the "O" Ring and the anaerobic sealer applied to certain areas when the cap is finally lowered in place and torqued down.

Ben and John can give a definitive understanding as to whether the oil channel hole in the block at the rear main journal ...or the cap itself... is either chamfered or grooved to accept the "O" Ring in question.

[siKKa]

if you removed the rear main cap and didnt see an "o" ring, and the master 60* genius book pic doesnt match... then slap it back together and put it in the "spare parts" bin

[60dgrzbelow0]

if you removed the rear main cap and didnt see an "o" ring, and the master 60* genius book pic doesnt match... then slap it back together and put it in the "spare parts" bin

Ahhh Yes...... and now perhaps we shall have to add your example ...to this "How To"...

http://people.howstuffworks.com/sarcasm.htm/printable

[bszopi]

Please remember, that book was published prior to the 3x00 release, so what you are quoting may not be relevant.

[mgbv6]

This information is quoted from Tom Currao's arcane book, "How to Re-Build Your GM V-6 60* Engine" ...

Page 112 Photo Insert:

"Four types of Rear Main Seals in the 60 Degree V6, in chronological order:
1. Two Piece Rope-Type
2. Two Piece Lip-Type
3. 5mm One Piece Lip-Type
4. 10mm One Piece Lip-Type

If your engine was fitted with either of the first two seals, throw them out and use the 5mm One Piece Seal. The Ten mm Seal is used on all Large Journal Cranks and can be installed with the crankshaft in position."

And regarding the "O" Ring matter...

From page 113...an excerpt out of seven paragraphs on the install procedures...

"Some Early Blocks and all Late Model Blocks use an "O" Ring to seal the Rear Main Bearing Cap to the block to reduce oil leakage between the cap and the block. The "O" Ring should be installed without any sealer to prevent it from slipping out of position..."

The remaining information on the page deals with the abundance of caution needed when sort of pre-installing the cap in such a manner that prevents the slippage of the "O" Ring and the anaerobic sealer applied to certain areas when the cap is finally lowered in place and torqued down.

Ben and John can give a definitive understanding as to whether the oil channel hole in the block at the rear main journal ...or the cap itself... is either chamfered or grooved to accept the "O" Ring in question.

Question: Do I need the special tool to do this or can I just tap it in place? My engine is sitting on the working bench right now. TY in advance

[pocket-rocket]

I use a block of wood and a hammer to tap a rear main back in. I also don't beat it like a rented mule, I tap it in.

[60dgrzbelow0]

This a very generic but excellent video describing an "In Vehicle" Rear Main Oil Seal Replacement (Crankshaft Steel Oil Seal Installation)

http://www.youtube.com/watch?v=bKayjFhOXc4

And here is one for replacing the Front Engine Oil Seal in a transverse GM 3.1L Engine. I'm not crazy about the mechanic's lack of cleanliness in preparing the "operating field" work area to remove the dirt and grease before opening up the motor. Also... framming on the Harmonic Balancer with a Lead Sledge the size of Thor's Hammer "Mjöllnir" to re-install the Harmonic Balancer may de-tune the crankshaft as well. Nonetheless, this is a rare 60* basic engine repair video that is still worth watching.

I would also urge the use of a large wire wheel 3/8" bit brush to go over the Harmonic Balancer and remove all that heavy rust scale and old factory paint... (Using thick leather gloves and a full face shield while doing this part of the job is a good idea to prevent pieces of the wire wheel that will fly off from striking your face and eyes with these dart-like projectiles that always fly off during this work).

Before re-installing the HB, place a dollop of HTV Silicone inside the HB key-way groove after giving it a good dousing with Spray Brake Cleaner to remove all traces of grease and oil, Doing this will ensure a seal along the length of the crankshaft nose where oil might ordinarily seep out from within the areas where the Woodruff Key mates imperfectly to the crankshaft groove and FUBAR the job indirectly ...with or without a new front cover seal installed.

http://www.youtube.com/watch?v=rYTDMwxw4Ds

[Rootie524]

i put everything back together in my car and when i started it it ran perfect. i let it go for like 30 seconds. i get out. look under the car. and pretty much all the oil i put in was now on the floor. looks likes its coming from the rear main seal. face..palm...

idk how this could have happened. i squared it in there. and it was in there good. needless to say im pissed beyond believe and im taking a long break from this car. i dont feel like pulling the engine again for this bull shit.

[pocket-rocket]

I usually watch it and make sure the inner lip isn't folding over on itself to make sure it goes in right. I also run a film of oil over it to help it slide over the crank shaft and not snag up and fold over on itself too. That still sucks man...

[60dgrzbelow0]

i put everything back together in my car and when i started it it ran perfect. i let it go for like 30 seconds. i get out. look under the car. and pretty much all the oil i put in was now on the floor. looks likes its coming from the rear main seal. face..palm...

idk how this could have happened. i squared it in there. and it was in there good. needless to say im pissed beyond believe and im taking a long break from this car. i dont feel like pulling the engine again for this bull shit.

This is very unfortunate... That first video describes the problem of how much variation in OD can occur with everything from over-enthusiastic machining that when reducing the OD on the crankshaft,,,will wind up making it impossible to have a stock PTFE w/ wire coil internal style Engine Oil Seal to close up that gap. It may well be that if your engine was re-built by someone else, they may have already treated a grooved surface with either a "Redi-Sleeve" or in the case of the video... a "Full Circle" steel sleeve to return the crankshaft to a condition where it will hold the seal. The outer rubber area that is just in front of the space where the coil hides inside is also subject to tearing or puncturing if roughly installed with say a block of wood with splinters and sharp ends that can cause seal damage during replacement. Please don't be too discouraged. This has happened to all of us at one time or another for a variety of unforeseen reasons.

Is there any chance that the oil is leaking out of the top of the engine at a failed Oil Pump Drive Seal instead? Or ...perhaps, however unlikely it seems...a puncture in your oil filter body?