my rear main on my 455 is leaking are they 1 piece or 2?? Can you change them by dropping the tranny? Tranny shop is working on my car and said they would change it if it is a one peice and they don't have to take off a cover?? Anyone know if local parts store carries them and which one. Car is not raced
Fer real? Ive done rods and mains and the rear main seal with the trans in and oil pan off. I think the oil pan would be easier to pull now with the trans outa the way. JMHO... ws
It is two piece. The only way to change it properly is to pull the crank. You can pull the engine and pull the rod caps off, push the pistons in the bores, pull the main caps, timing cover, timing chain then the crank. Not too hard but lots of work. The following link is the best write up and you can use it on a rubber seal. http://www.v8buick.com/index.php?threads/bop-455-rear-seal-install-step-by-step.301130/
Can you explain how you did it like that?? I'm confused everyone says motor out, tranny out, now just pull oil pan?? One piece, two??
It's possible but here's the pit falls 1. Getting a good oil pan seal with engine in the car = highly unlikely 2. Getting all the old rope seal out of the upper groove= maybe 3.damaging the new seal trying to roll it around the crank because the rope didn't come out cleanly= 50/50 chance The trans is out, there is now only some hoses , wire harness with line 10 connections and two engine mount bolts holding it in. Pull the engine or have it pulled psi wash all the mess off, put it on a stand and do it once not 3times.jmo But to answer one of your questions it uses a two piece rope seal which most everyone upgrades to the neoprene 2 piece seal
How it would be done with the engine in the car is as follows (I dont recommend this be done in the car.) remove the pan and the rear main cap. Using some sort of punch push the end of the seal that goes over the crank in one side and pull out the other. Take 1/2 of your new seal and push into the guide until 1/8" sticks out the other side. with the main cap on your bench do the same with the other 1/2 of the seal leaving the opposite end sticking 1/8th " out so that when you put the cap back on, the end of the seal on the cap goes into the recess left in the block and the nub sticking out of the block goes into the cap. The idea is not to have the parting line of the seal line up with the parting line on the main cap. do not use any type of sealer. Good luck.
Laughing in the face of adversity, as a 17 year old kid, in the dead of winter in an unheated garage, my only mode of transportation was my 1971 GS455, alas, with a rod knock. Before it became a crankshaft issue, I decided to pull the pan and change the bearings et al. All that was really required to get the pan off, was to unbolt the motor mounts and jack the block up until it bottomed out in the tunnel. If I recall, I rested it back down on a pair of 4x4s. There was probably one or two crank throws in the way so the unit had to be rolled over into position as the pan came out. With all the main caps loose, the crank dropped down about .050" give or take. One at a time, I pulled the caps and inserts and rolled new ones in. The rear main had to come off to pull the rope seal(?) and roll a neoprene unit in. The whole job was done with a single drop light and hand tools. After the mains were all back together, a test roll confirmed the bottom end would roll so it was then on to the rods; one at a time with plastigage to verify clearances. IIRC, the replacement rod bearings were STD's or .0005" under. Jim Weise and I had this conversation a month ago. Alas, the .0005"u.s. bearings are no longer available. It can be done, just keep the hand cleaner stuff at the ready LOL... ws
If I were you I'd just put trans in then take to shop that knows old cars , most of your average mechanics don't have the skill set to work with cork gaskets , two piece seals etc they are used to idiot proof gaskets and seals that's my experience anyway, I've got lots of friends with lots of training and do well in their fields but when something old comes in they are lost
I have done it with the engine in the car. It helped to loosen all main caps and remove the rear one to get a bit of clearance between crank and upper brng to r/r seal
I did it from underneath with my 72 350. I thought it was pretty easy, BUT, it was a relatively fresh rebuild with a rope seal that leaked. I replaced it with a ford 460 seal. That's a big "BUT". Not sure what you will run into with something old. The pan will come right out by raising the engine a little. No need to even take the starter off.
Even though it may take a few hours to prep for the engine removal, DO IT. It is so much easier with the motor on an engine stand. Besides, u can they replace other gaskets and seals and repaint the engine
I have done it both with the engine in and the engine out. And both ways have advantages... If the trans is out then it's a heck of a lot easier to do the job but the shop would have to remove your flexplate, lift the engine, remove the oil pan, remove the rear cap, use a stiff wire to push the old rope seal out... I had no issues getting the top part of the old rope seal out with just the main cap removed and all the other mains left tight. To save on time ($) and to make sure it's done right I would tow the car home while the trans is out and do the rear main myself then bring it back for the trans instal... But I own a tow truck so no cost there.
Ive never had a problem rolling an "in situ" seal out either by pushing or pulling. If pushing it with a hammer-n-punch always use something softer than the crack journal, i.e. brass or aluminum. Bend a gun cleaning brush to roll around and wash the fit clean. You can also pull the rope out with a cork screw packing puller. The flex plate can stay but gives you a ton of extra room to work around. Id also plastigage the clearance and reset the rear main thrust as per the book. Its not a biggy, and if you've never done it will make you a better mechanic for it. ws https://www.google.com/search?q=cor...57DVAhUB7oMKHZ8FBAgQ_AUICygC&biw=1261&bih=549
