Rear main seal replacement instructions
Melting Slicks
Joined: Oct 2006
Posts: 2,417
Likes: 336
From: Texas
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Did the '68 engine really have a rope seal??? 
Get rid of it and install a new Viton lip seal pack!
P.S. If you do have to remove the old rope seal, you may have to loosen the main bearing caps (in 'tapered' fashion; lower toward rear main and just loose at the front) so that you can 'free' the rope seal for removal. As long as you don't jostle any bearings from there caps nor get any debris in them, they will just go back in place when you torque them down. MUCH easier that way.
Get rid of it and install a new Viton lip seal pack!
P.S. If you do have to remove the old rope seal, you may have to loosen the main bearing caps (in 'tapered' fashion; lower toward rear main and just loose at the front) so that you can 'free' the rope seal for removal. As long as you don't jostle any bearings from there caps nor get any debris in them, they will just go back in place when you torque them down. MUCH easier that way.
Thread Starter
Cruising
Joined: Apr 2014
Posts: 13
Likes: 0
Thanks much
Did the '68 engine really have a rope seal???
Get rid of it and install a new Viton lip seal pack!
P.S. If you do have to remove the old rope seal, you may have to loosen the main bearing caps (in 'tapered' fashion; lower toward rear main and just loose at the front) so that you can 'free' the rope seal for removal. As long as you don't jostle any bearings from there caps nor get any debris in them, they will just go back in place when you torque them down. MUCH easier that way.
Get rid of it and install a new Viton lip seal pack!
P.S. If you do have to remove the old rope seal, you may have to loosen the main bearing caps (in 'tapered' fashion; lower toward rear main and just loose at the front) so that you can 'free' the rope seal for removal. As long as you don't jostle any bearings from there caps nor get any debris in them, they will just go back in place when you torque them down. MUCH easier that way.
Burning Brakes
Joined: Dec 2010
Posts: 945
Likes: 10
From: Winston Salem NC
Speedreed has the link I used.
Key points: get the seal that has the lip moved further back. This repositioned lip will wear on a section of the crank that is not worn.
Shift the seal ends so that they are NOT alighned with the bearing cap. Ex. the ends of the seal should be at 2 and 8 o-clock whereas the bearing cap is at 3 and 9 o-clock.
Apply silicone to the ends of the seals and on the bearing cap.
I did mine 2 years ago and it has stayed leak free.
Key points: get the seal that has the lip moved further back. This repositioned lip will wear on a section of the crank that is not worn.
Shift the seal ends so that they are NOT alighned with the bearing cap. Ex. the ends of the seal should be at 2 and 8 o-clock whereas the bearing cap is at 3 and 9 o-clock.
Apply silicone to the ends of the seals and on the bearing cap.
I did mine 2 years ago and it has stayed leak free.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
You can only offset the seal halves about 1/4" and still get it assembled without damaging it. I also agree that offsetting it a bit (1/8-1/4") is a good idea so that the seal splitline does not line up with the bearing cap splitline. When installing the seal halves, put just a very small dab of black RTV sealant (ONLY black RTV sealant) in the center of one end on each half. When they go together, the sealant will tend to bond both halves...but not have so much as to spread out beyond the face of the seal.
