The Stovebolt Site Forums The Shop Area Engine Shop Rear main seal advice?

I tried the search and it tells me no results. Anyway, the 270 engine seems in very good condition, no smoke, starts and runs fine.
But in the near future it is gonna need a rear main seal. Guess it set up and dried out.
Are these engines known for leaking seals?
Would NAPA be as good as any, to get the seal and the tools to install it? I want to do it in the truck, it does not need anymore engine work.

The only rear seal I would use is a "Best Gasket" brand (sample)

Rope seal with the engine in the truck is a PITA. It can be done, and there are some tips in search. Just probably not for the 270. GM is a different beast. The trick is to drop the crankshaft while under the truck. So you get to remove the rear main bearing cap. Then loosen all the others until the crankshaft will drop down some. The front cap should not be removed. You want the back end of the crank to move down not drop out. I have also had to remove the bolts that hold the transmission to the Bell Housing and push the transmission back a bit to let the crankshaft drop. Are we having fun yet? There is a tool, called a Sneaky Pete that will screw, into the seal and help remove the 1/2 that is in the block. The same tool is used to tease the seal into the block while you turn the crankshaft to ease it around. I have had limited success with the technique. Sometimes I can get it to work, and other times....well you get the drift. When the seal is in it will need to be trimmed flush at the block. The other half is easy cause you have the bearing cap out and in your hands. Use the manual to help with this part. Again trim flush, put a dab of black sealer on the ends in the cap and re install. Torque all the bearing caps, re install the bolts for the transmission, Replace the oil pan, and dust covers and you are good to go. Best seal is from Best gaskets. Is there a neoprene seal for the 270? I don't know. I have used them in 235's with great success. Much easier to change, and install.

Thanks guys. I think still that would be easier and more sensible than pulling the engine and doing a complete tear-down just for a seal.
I have not checked on what seals are available for the 270 yet.
I did find the tool and a seal for the 270 on the e-bay site, referred by Pre 68 Dave.
Does the Sneaky Pete work like one of the toys that you put on your finger and try to pull off?
I remember using one like that in the old days, but don't remember what success we had.

One trick I like to use is to form the block half of the gasket in the cap, then when you go to install it, it fits much easier around the crank and it should drop into place. Just don't trim the ends till its up in the block. You will need to form it a couple of times to get at least one end and enough to go around half the crank.

Take the time to order a seal from Best, nothing else will seal like they do, or I should say no other rope type material will seal like they do.

One thing I will add to the "Best Gasket" recommendation.
The instructions say to drill the cap and install a pin through the hole into the seal to keep the seal from slipping. I do not do this, or see the need.

Thanks guys, good tips. I don't see the need for a pin either. How can it go anywhere after you install the cap & use the black sealer at the ends?
Another thought: I know oil usually makes leather and other materials swell up. Would using some silicone spray help the upper one to slide in? Or is it best to just install them dry?

I usually soak a rope seal in oil before I install it. I have never used a Best brand main seal so I'm not sure what they recommend to use if anything when installing one.

You will need some lubricant but I wouldn't soak the Best seal in oil. I couldn't use the Sneaky Pete to pull it in but I used a piece of picture hanging wire.

So, I am guessing the Sneaky Pete does not have the web design, I mentioned above, about the finger toy? In other words, the tighter you pulled on it, the tighter it would grip the rope.
I think the ones we used in the old days had that web, or whatever the correct word is.
I think they worked very good.

Chinese finger.

http://en.wikipedia.org/wiki/Chinese_finger_trap

http://www.toolsource.com/sneaky-pete-seal-removerinstaller-p-70870.html

Click on above link and you can see the KD Sneaky Pete

Yeah! I had forgot what those were called.

The seal is pretty slick all ready, lots of graphite on the out side. I agree, no need to pin them, and no need to use sealer on the ends. In fact, follow the direction just like printed.

Joe

Thanks very much to all! It is not a top priority project just now, but soon.
I have saved all this info. and links.