4150/3247
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1966 3869942 rear main seal two piece and which seal recommended ? Any special tips on installation would be appreciated
rear main oil seal
- Thread starter 4150/3247
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- Edgerton, Ohio, United States
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- 1959 black 270hp (9/2/69) 1981 Beige L81(10/20/80)
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Replacing the rear main seal is pretty easy and straight forward. Drop the pan, oil pump and rear main cap. Note the orientation of the seal in the cap and pull out the old and insert the new. The upper half can be easily rotated around the crankshaft by tapping on one end of it with a small punch. It will rotate around far enough to grab the other end with pliers and continue to rotate it until it's out. Apply a little motor oil to the new one and rotate it back in until both ends are flush. Wipe the rear main bearing to be sure it's clean and apply a little clean motor oil to the bearing face. Re-install the cap and torque to specs.
Sometimes you will find a worn area on the crank journal where the seal contacts. If it's bad enough a new seal may have a hard time sealing. Thanks to NAPA this is not a problem. They make a rear main seal with an offset lip so that the contact area is moved over slightly to an unworn place on the crank journal. It's like brand new all over again.
If you want to make your life easier I highly recommend using a Fel Pro one piece oil pan gasket. I get them from Summit. They come in both thick and thin front seal area depending on the year of your engine and pan. Yours should be the thin one. These are a dream when working under the car. Once all of the old gasket is cleaned off and the sealing surface is clean you apply a small dab of sealer (comes in the package) to the corners of the front and rear main cap. Then push the gasket up into place. The kit comes with several plastic retainers that fit in the pan bolt holes that hold the gasket in place while you are installing the pan. The retainers slip through the bolt holes in the oil pan and, once you have the other bolts installed, simply are removed and replaced with the remaining bolts. The only downside with this gasket is that it is blue and guys getting their cars judged don't want blue. The big upside is that you don't have to juggle multiple pieces and it isn't cork on the side rails. It should last forever.
Be sure to check the gasket rail on the oil pan for distortion from over tightening sometime in the past. If the bolt holes are pulled straighten them if you can or replace the pan if it's severe. Torque the pan bolts to specs so that the pan rails don't get distorted and cause leaks. You will need an inch lbs torque wrench for the pan bolts.
Tom
Replacing the rear main seal is pretty easy and straight forward. Drop the pan, oil pump and rear main cap. Note the orientation of the seal in the cap and pull out the old and insert the new. The upper half can be easily rotated around the crankshaft by tapping on one end of it with a small punch. It will rotate around far enough to grab the other end with pliers and continue to rotate it until it's out. Apply a little motor oil to the new one and rotate it back in until both ends are flush. Wipe the rear main bearing to be sure it's clean and apply a little clean motor oil to the bearing face. Re-install the cap and torque to specs.
Sometimes you will find a worn area on the crank journal where the seal contacts. If it's bad enough a new seal may have a hard time sealing. Thanks to NAPA this is not a problem. They make a rear main seal with an offset lip so that the contact area is moved over slightly to an unworn place on the crank journal. It's like brand new all over again.
If you want to make your life easier I highly recommend using a Fel Pro one piece oil pan gasket. I get them from Summit. They come in both thick and thin front seal area depending on the year of your engine and pan. Yours should be the thin one. These are a dream when working under the car. Once all of the old gasket is cleaned off and the sealing surface is clean you apply a small dab of sealer (comes in the package) to the corners of the front and rear main cap. Then push the gasket up into place. The kit comes with several plastic retainers that fit in the pan bolt holes that hold the gasket in place while you are installing the pan. The retainers slip through the bolt holes in the oil pan and, once you have the other bolts installed, simply are removed and replaced with the remaining bolts. The only downside with this gasket is that it is blue and guys getting their cars judged don't want blue. The big upside is that you don't have to juggle multiple pieces and it isn't cork on the side rails. It should last forever.
Be sure to check the gasket rail on the oil pan for distortion from over tightening sometime in the past. If the bolt holes are pulled straighten them if you can or replace the pan if it's severe. Torque the pan bolts to specs so that the pan rails don't get distorted and cause leaks. You will need an inch lbs torque wrench for the pan bolts.
Tom
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- #3
4150/3247
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Thanks Tom going to be Jan/Feb project
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