The Stovebolt Site Forums The Shop Area Engine Shop rear main seal removal

can anybody tell me how to remove the upper rear main seal with the block still mounted in the truck and without taking the crankshaft out? any suggestions would be appreciated.

You may have to remove the transmission to allow the crank to drop a little bit when you loosen the main caps.

is it possible to do this without removing the transmission?

would burning it be an option or is there another method that could be used? (everything else block, transmission, torque tube, and rear are still in place)

Could you push or pull on it while rotating the crankshaft?

Joe

we tried to push and pull while rotating it and we had no success but we are trying different methods because its been in there so long it is stuck in place

Loosen all the main bearing bolts 2-3 turns or so to let the crankshaft drop away from the seal a little, and then screw a long sheet metal screw into the seal. Grab the head of the screw with vise grips, and pull/pry on the vise grips to get the seal moving. Be careful not to scratch the surface of the crankshaft or you'll damage the new seal the first time the crank turns against it.
Jerry

We loosened the main cap bolts about 4-5 turns and the crankshaft did not move being it is still attached th the clutch, flywheel so we tried pulling little by little and got about an inch out on both sides. We started to make a tool out of sergeant pliers but had to call it a day because of a family occasion, will continue tomorrow.

Got mine out with a sneaky pete tool. This tool comes with a cork screw type wire to remove it and a cable and cuff type tool to install it. Can get this tool at most FLAPS. Made the job much easier removing the rear main seal and installing it. Just make sure you soak the new seal in oil before installing and feed the new seal in carefully.

I use a broken piece of coping saw blade to go up between the block and the seal to disturb its grip. Then I use the Sneaky Pete corkscrew. You may get the old one out but you won't get the new one in without dropping the crank.

( Taken from Deve's web site} To get a rope seal in there is tricky and starts with removing the torque tube bracket from the mid cross member, then removing the 4 bolts holding on the transmission. We need to slide the tranny back about 1/4 inch or so for the front bearing retainer to clear the pilot hole in the bell housing. This allows the transmission and crankshaft to drop together enough to remove and replace the upper seal. With everything loose, the Transmission will slide back easily, then we can proceed to loosen all four Crankshaft Main Caps. Do not remove them, just loosen. You want the crankshaft to drop down about 1/4" or so in the back so loosen the Front Cap but leave it in place, then loosen the mid/front cap a little more, then the mid/rear cap even a little more, then remove the rear cap completely. This may take some tweaking, loosening, etc, but you get the idea. With the caps sufficiently loose, the crank will come down enough to get the new seal in place.

Using Needle Nose Pliers, grab one end of the upper seal and pull down. Pull the old seal out of the cap as well. You will need to form the new upper seal in the cap first to ease installation in the block groove. Form it before cutting the seal. You want it to be extra long at this point. After the seal is formed you will be sliding it into place into the engine block. This can be done in many ways. There is a tool called a Sneaky Pete that grabs one end of the seal for pulling it around the crank and into place. It is also possible to poke safety wire through the seal near the end, feed the wire through the seal groove and pull the seal into place. Once the seal is in place, push the crank temporarily into place to seat the seal in its groove. This can be done by putting a jack under the flywheel. After the seal has been seated you will let the crank drop back down for cutting the ends. Once the crank is back down, slide a thin piece of metal against the crank side of the seal ends to support them while cutting them flush with the block. Once that is done, you can tighten and torque the front three main caps and put the transmission and mount back into place.

Form the seal in the cap and cut the seal ends leaving a slight bit of each end protruding. You want it longer so the two pieces sort of squash up against each other. Lay a thin path of gasket sealer from the seal area over to where the pan end gasket attaches and install and torque the rear cap. Torque the main bearing caps to 105 foot pounds and the rods to 40 foot pounds.

Will the tranny slide back with the inclosed driveshaft connected or will we need to disconnect it?

This can be done (and was described in some old Shop Manuals - for earlier torque-tube vehicles). I do not recommend this (for a variety of reasons), but I did it once. This was during a restoration, and all parts were new and brake fluid had not yet been put in the brake system.

I think Tim missed read the question, the trans will move back on the torque tube with out touching the torque tube.

It has been my experience that the seal made by Best gasket is not only a good product but they are at least an inch longer than needed. With some of the other ones, there is not enough length to use the Sneaky Pete mesh and still remove it after the pull is complete.

we took the tranny out than lowered the crank a little bit more than stuck a zip tie into the hole where the seal goes which loosened the seal than with the pliers we ripped it out and installed a new neoprene seal in its place. thank you for all those who gave us word of advice to removing the old seal.