I have installed my neo rear main seal, but I have a few questions: 1) A small bit of neoprene was shaved from the outside of the seal when I installed it. This seems unimportant, as the sides and edge that rides the crank was not in any way damaged. this was on the top (block) half. Is this actually a non-issue? 2) I installed each half flush with the block and cap mating surfaces. is this correct? It seems to be 3) should a small dab of rtv have been used where the halves of the seals meet? I didn't think so, but it's worth asking about
Some guys like to tilt them so the joining surface is inside the block or cap bore. Not much is needed, maybe a 10-20 degree tilt. I've done several engines - Buick and otherwise - and had the seal flush with the flat surfaces, not used sealer on the seal joining surfaces and had no problems.
The place where leaks start is between the rear cap and the block. You need to put a very thin bead of sealer on the car and block adjacent to the seal. The factory servioce manual shows exactly where. This is key to preventing oil leaks.....Ask me how I know!
Um, my 1970 Buick "All Series" chassis manual is right next to me, and they only mention neoprene for the 350. Rope is called for on the 455 in the 1970 Manual. For the 350, they say that you should soak the seal in light oil or kerosene to swell it, and that it may leak for a short period It mentions nothing about a bead of sealer, much less where to place it. Maybe you have a different year service manual than I do, Paul? But thanks for the input. :TU:
Absolutely, Jim I'm not sure how I've confused you, but I'm not asking whether or not I should use a rope seal, or saying you shouldn't use a neoprene one because the manual says you should use rope. All I'm saying is that the 1970 manual doesn't show use of a neoprene rear main seal in a 1970 455 block, only in the 350 block.
Chris, As much as you don't want to, take it back apart, and do not line the seal ends up flush with the block and cap. Some may get away with this with the use of sealer, but your asking for trouble.. Clean the grooves completely, then take a center punch and make a bunch of punch marks inside the groove, on both sides. Don't go nuts here, your just trying to raise the surface a little to get some "teeth" on the seal. An automatic center punch works very well for this. Chamfer the edge of the block and the cap (will be on opposite sides), where the free end will be installed in the cap/block. For clarity, we are going to call the end of the seal that will be hanging out of the block/cap the "free end". Use "The Right stuff" sealer behind the seal.. install a little in the groove, take a Q-tip, rip most of the cotton off the ends, and use it to spread the sealer out to a very thin layer, except where the "free end" of the seal in the cap will go in the block. Repeat this entire process in the cap. Once again, don't get any sealer where the cap will receive the "free end" of the seal in the block. Now, install the seal, leaving one end in the block about 1/8-1/4 of an inch, orient the cap seal properly with roughly the same positioning of the seal. Lubricate the lip of the bottom half of the seal (making sure the lip "points" toward the inside of the engine). After setting the seal in place, push down on the "free end" with you finger, while holding the end down in the block with a screwdriver. Your working to "seat the seal". Remove any excess sealer that oozes out around the seal. Especially on the inside. Repeat this process in the cap. Drop the crank, but do not spin it. Take the cap, and put a very light coat of sealer on the sealing porting of the cap. Install the rear cap first, after making sure the seal lip is pointing in toward the engine, is installed so it's "free end" mates with the end of the seal that is recessed in the block. Do not put any sealer on the either end of the seal. Work the rear cap into place carefully, you will feel the seal drop in the hole. Always tip the cap, so the side that the seal is going into the block, goes in first. Align the cap holes with the bolt holes by using the bolts as a gauge, or just your eye, and tap the cap down on the other side with a crisp blow, at about a 45* angle. Install the rear bolts, and just snug them up, install the rest of your caps, and then go thru the thrust bearing positioning process, and tighten all caps in 3 steps to the torque used when you had the block align honed, with the same lube your machinist used. I don't spin the crank till I have at the caps at the first 30 ft lbs increment. I have yet to ever have a TA no trim seal leak, and prolly have installed 30 of them in the last couple years. One of my customers just did one this spring, and lined the ends up flush with the cap/block, and it leaks like a sieve.
I think I would follow Jims' advice and install it just as he describes. I didn't and now have to pull my engine back out to fix an annoying drip. Thanks Jim for being discrete and not using my name in your example of how not to install a seal.
I don't have a TA seal, I got mine from Geoff Ketchum. Nice guy. I imagine it's the same type of deal though
