Rear Main Seal
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Pro
Joined: Sep 2004
Posts: 611
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From: Minnesota
Rear Main Seal
I will be replacing my rear main seal. I am looking at the Felpro seals. Which matrial type should I buy rubber, silicone, polyacrylate, or flouro-elastomer? Any tips of tricks to putting this in?
Last edited by captainmorgan; Apr 25, 2006 at 02:47 PM.
Melting Slicks
Joined: Oct 2004
Posts: 2,662
Likes: 8
From: Knoxville Tennessee
Although I have used the felpro single piece gasket with great success on my 7 qt. oil pan (no leaks) I did not use them when I replaced my leaking 2 piece rear main seal. I used a stock seal.
After draining the oil and removing the oil pan ( I had to unbolt the 2 bolts holding the idler arm on the right side of the frame to lower the steering linkage), remove the oil pump; two bolts and the shaft going to the distributor. Be careful there is a fiber bushing connecting the oil pump shaft to the distributor shaft. I broke mine; another fiber bushing is cheap and available at most auto stores but I replaced my old pump with a melling high volume oil pump. It comes with a metal bushing. If you want to replace your pump a standard melling pump is fine too. Next, remove the rear main cap that has the seal in it. The top half of the seal will still be in the block. With the transmission still in the car it is a little tighter to remove and install but you can do it. With the cap removed take a drift and lightly tap on the end of the seal until it starts to move; then you can grab it with a pair of pliers and pull it from the cap. Before removing the seal, make sure you orient the cap remembering which goes toward the inside of the engine; look at the seal and notice which way the lips of the seal are leaning. They are leaning toward the inside of the engine. This keeps the seal from leaking when the oil pump puts oil pressure on the inside of the seal. If it installed with the lip of the seal leaning towards the outside the seal will leak great amounts of oil. Next take a long slender drift and tap on one end of the seal in the block. Keep tapping on it until it has moved around the block and you can grab it with a pair of pliers. Be sure not to let the drift come in contact with the metal parts of the block. Scratching could cause a leak. If a friend is handy you could continue tapping on the seal while he pulls on the seal. Once it has moved substancially the pliers can pull it the rest of the way out. Now install one half of the seal into the cap making sure the lip of the seal is leaning in. Some people say to leave about a quarter inch sticking out of the cap and installing the other half so that the exposed part of the seal will go into the block and the exposed part of the seal in the block will go into the cap. This is supposed to help keep the seal from leaking where the cap mates to the block. I installed my seal with it even in the cap. Then lightly lubricate the other half of the seal and begin working it back around the crank into its groove on the block until it is completely in the block. I used a small dab of high temp RTV on each end of the seal but others will tell you not to. Both work. Once the seal halves are in place install the cap and torque it to the specified torque, install the oil pump and shaft making sure the shaft mates to the destributor, torque those 2 bolts, install the oil pan and I highly recommend the one piece felpro gasket for about $25.00. Now you are done. This is the way I installed mine and it is leak free. The other way I mentioned works too.
Bernie
After draining the oil and removing the oil pan ( I had to unbolt the 2 bolts holding the idler arm on the right side of the frame to lower the steering linkage), remove the oil pump; two bolts and the shaft going to the distributor. Be careful there is a fiber bushing connecting the oil pump shaft to the distributor shaft. I broke mine; another fiber bushing is cheap and available at most auto stores but I replaced my old pump with a melling high volume oil pump. It comes with a metal bushing. If you want to replace your pump a standard melling pump is fine too. Next, remove the rear main cap that has the seal in it. The top half of the seal will still be in the block. With the transmission still in the car it is a little tighter to remove and install but you can do it. With the cap removed take a drift and lightly tap on the end of the seal until it starts to move; then you can grab it with a pair of pliers and pull it from the cap. Before removing the seal, make sure you orient the cap remembering which goes toward the inside of the engine; look at the seal and notice which way the lips of the seal are leaning. They are leaning toward the inside of the engine. This keeps the seal from leaking when the oil pump puts oil pressure on the inside of the seal. If it installed with the lip of the seal leaning towards the outside the seal will leak great amounts of oil. Next take a long slender drift and tap on one end of the seal in the block. Keep tapping on it until it has moved around the block and you can grab it with a pair of pliers. Be sure not to let the drift come in contact with the metal parts of the block. Scratching could cause a leak. If a friend is handy you could continue tapping on the seal while he pulls on the seal. Once it has moved substancially the pliers can pull it the rest of the way out. Now install one half of the seal into the cap making sure the lip of the seal is leaning in. Some people say to leave about a quarter inch sticking out of the cap and installing the other half so that the exposed part of the seal will go into the block and the exposed part of the seal in the block will go into the cap. This is supposed to help keep the seal from leaking where the cap mates to the block. I installed my seal with it even in the cap. Then lightly lubricate the other half of the seal and begin working it back around the crank into its groove on the block until it is completely in the block. I used a small dab of high temp RTV on each end of the seal but others will tell you not to. Both work. Once the seal halves are in place install the cap and torque it to the specified torque, install the oil pump and shaft making sure the shaft mates to the destributor, torque those 2 bolts, install the oil pan and I highly recommend the one piece felpro gasket for about $25.00. Now you are done. This is the way I installed mine and it is leak free. The other way I mentioned works too.
Bernie
Melting Slicks
Joined: Oct 2004
Posts: 2,662
Likes: 8
From: Knoxville Tennessee
Desi,
It is a lot easier with the tranny removed but it is still very easy to do. Just be careful not to scratch anything as you remove the seal halves. Go slow and have patience; this is the key.
Bernie
It is a lot easier with the tranny removed but it is still very easy to do. Just be careful not to scratch anything as you remove the seal halves. Go slow and have patience; this is the key.
Bernie
Melting Slicks
Joined: Nov 2001
Posts: 2,668
Likes: 43
From: Eastern US XX
Originally Posted by BerniesVette
Although I have used the felpro single piece gasket with great success on my 7 qt. oil pan (no leaks) I did not use them when I replaced my leaking 2 piece rear main seal. I used a stock seal.
After draining the oil and removing the oil pan ( I had to unbolt the 2 bolts holding the idler arm on the right side of the frame to lower the steering linkage), remove the oil pump; two bolts and the shaft going to the distributor. Be careful there is a fiber bushing connecting the oil pump shaft to the distributor shaft. I broke mine; another fiber bushing is cheap and available at most auto stores but I replaced my old pump with a melling high volume oil pump. It comes with a metal bushing. If you want to replace your pump a standard melling pump is fine too. Next, remove the rear main cap that has the seal in it. The top half of the seal will still be in the block. With the transmission still in the car it is a little tighter to remove and install but you can do it. With the cap removed take a drift and lightly tap on the end of the seal until it starts to move; then you can grab it with a pair of pliers and pull it from the cap. Before removing the seal, make sure you orient the cap remembering which goes toward the inside of the engine; look at the seal and notice which way the lips of the seal are leaning. They are leaning toward the inside of the engine. This keeps the seal from leaking when the oil pump puts oil pressure on the inside of the seal. If it installed with the lip of the seal leaning towards the outside the seal will leak great amounts of oil. Next take a long slender drift and tap on one end of the seal in the block. Keep tapping on it until it has moved around the block and you can grab it with a pair of pliers. Be sure not to let the drift come in contact with the metal parts of the block. Scratching could cause a leak. If a friend is handy you could continue tapping on the seal while he pulls on the seal. Once it has moved substancially the pliers can pull it the rest of the way out. Now install one half of the seal into the cap making sure the lip of the seal is leaning in. Some people say to leave about a quarter inch sticking out of the cap and installing the other half so that the exposed part of the seal will go into the block and the exposed part of the seal in the block will go into the cap. This is supposed to help keep the seal from leaking where the cap mates to the block. I installed my seal with it even in the cap. Then lightly lubricate the other half of the seal and begin working it back around the crank into its groove on the block until it is completely in the block. I used a small dab of high temp RTV on each end of the seal but others will tell you not to. Both work. Once the seal halves are in place install the cap and torque it to the specified torque, install the oil pump and shaft making sure the shaft mates to the destributor, torque those 2 bolts, install the oil pan and I highly recommend the one piece felpro gasket for about $25.00. Now you are done. This is the way I installed mine and it is leak free. The other way I mentioned works too.
Bernie
After draining the oil and removing the oil pan ( I had to unbolt the 2 bolts holding the idler arm on the right side of the frame to lower the steering linkage), remove the oil pump; two bolts and the shaft going to the distributor. Be careful there is a fiber bushing connecting the oil pump shaft to the distributor shaft. I broke mine; another fiber bushing is cheap and available at most auto stores but I replaced my old pump with a melling high volume oil pump. It comes with a metal bushing. If you want to replace your pump a standard melling pump is fine too. Next, remove the rear main cap that has the seal in it. The top half of the seal will still be in the block. With the transmission still in the car it is a little tighter to remove and install but you can do it. With the cap removed take a drift and lightly tap on the end of the seal until it starts to move; then you can grab it with a pair of pliers and pull it from the cap. Before removing the seal, make sure you orient the cap remembering which goes toward the inside of the engine; look at the seal and notice which way the lips of the seal are leaning. They are leaning toward the inside of the engine. This keeps the seal from leaking when the oil pump puts oil pressure on the inside of the seal. If it installed with the lip of the seal leaning towards the outside the seal will leak great amounts of oil. Next take a long slender drift and tap on one end of the seal in the block. Keep tapping on it until it has moved around the block and you can grab it with a pair of pliers. Be sure not to let the drift come in contact with the metal parts of the block. Scratching could cause a leak. If a friend is handy you could continue tapping on the seal while he pulls on the seal. Once it has moved substancially the pliers can pull it the rest of the way out. Now install one half of the seal into the cap making sure the lip of the seal is leaning in. Some people say to leave about a quarter inch sticking out of the cap and installing the other half so that the exposed part of the seal will go into the block and the exposed part of the seal in the block will go into the cap. This is supposed to help keep the seal from leaking where the cap mates to the block. I installed my seal with it even in the cap. Then lightly lubricate the other half of the seal and begin working it back around the crank into its groove on the block until it is completely in the block. I used a small dab of high temp RTV on each end of the seal but others will tell you not to. Both work. Once the seal halves are in place install the cap and torque it to the specified torque, install the oil pump and shaft making sure the shaft mates to the destributor, torque those 2 bolts, install the oil pan and I highly recommend the one piece felpro gasket for about $25.00. Now you are done. This is the way I installed mine and it is leak free. The other way I mentioned works too.
Bernie
Great writeup.
A few of comments/suggestions:
- Rather than a drift, a better "tool" is a piece of wood - no risk of scoring the crank / block in case of an "oops"
- If the seal is stuborn, you can turn the crank while pushing (with the wood) on the seal - it will help the seal get started when removing. When installing, again, you can turn the crank if necessary while pushing the seal in as it will help the seal wrap around.
- Staggering the seal joints 1/4" or so with the cap joints is highly recommended. If you let the seal joints meet the cap joints, there really is a much greater potential of leaking.
- As you mentioned, silicone is not recommended on the seal ends. It recommended that you use the old Permatex Non-hardening gasket sealer (the sticky, smelly, dark brown stuff).
Paul
Melting Slicks
Joined: Oct 2004
Posts: 2,662
Likes: 8
From: Knoxville Tennessee
Paul,
Thanks for the additional suggestions! New methods are good to know when making a repair on something that is prone to start leaking over time. If I ever have to do mine again I will try them!
Bernie
Thanks for the additional suggestions! New methods are good to know when making a repair on something that is prone to start leaking over time. If I ever have to do mine again I will try them!
Bernie
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Burning Brakes
Joined: Feb 2006
Posts: 1,024
Likes: 1
From: AL
you can use hardwood dowels readily available from home shops; or you can fashion a tool out of the handle of an old toothbrush.
check this site for more info on sealants:
http://www.permatex.com/products/automotive.htm
be sure to check out this section:
http://www.permatex.com/resource_auto_prodselect.htm
check this site for more info on sealants:
http://www.permatex.com/products/automotive.htm
be sure to check out this section:
http://www.permatex.com/resource_auto_prodselect.htm