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| Rear Main Oil Seal; 10.03 Crankshaft | |
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| Tweet Topic Started: Oct 20 2008, 09:20 PM (2,093 Views) | |
| haroldk | Oct 20 2008, 09:20 PM Post #1 |
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On a 1954 CJ 3B, is it possible to replace the upper half of the rear main oil seal without dropping the crankshaft? |
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| Don | Oct 22 2008, 07:26 PM Post #2 |
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haroldk, This is a copy of a pervious post. ==== Yes,, sometimes it is possible to replace the crankshaft rear bearing seal if,,,,,,,, the upper part of the seal isn't "glued" to the engine block with some type of sealer, and if,,,,, the Willys Gods are in a good mood that day. Basically you remove the oil pan, (drain the oil first ;>) remove the rear bearing cap, and loosen the bolts for the center and front bearing cap for the crankshaft. This should allow the crankshaft to droop just a little bit. You then push the old upper half of the seal out by pushing the new one in the same grove. Then replace the lower half of the seal that is in the rear bearing cap. Bolt it all back together. YEA !!!! GOOD JOB !!!! No more leaks !!!! WELL<< WE HOPE>>>> A few details now,,, I suggest you have on hand new; rear main bearing seal, 2 pieces, rear main bearing packing, 2 pieces (I used Felpro Rear Main Bearing Set # BS 3165 which contains both) and the oil pan gasket (I used Felpro QS 4350 AD) #2 Permatex A bunch of clean rags to wipe oil out of your face. This ain't a 15 minute job. Give yourself plenty of time. When you remove the oil pan, look at the 6 bolts that hold the crankshaft pulley guard in place. They have spacer washers on them and they are longer than the other 14 oil pan bolts. (if original) Be very careful as you work to slide the old seal out of the block. I read of a fellar that knocked the bearing loose and also dislodged the bearing dowel. He talked like it was a problem to get back in place. As you're working, try to keep the ends of the seal dry as you're gonna want to put some sealer on the ends where the two halves meet just before you put the bearing cap back in place. You will want to oil the seal where it rides on the crank shaft and the engine block before you start installing it. When you get the seal in the block, leave one end up in the block about an 1/8 inch above the joint of the bearing cap. This offset is suppose to help the sealing of oil. While you have the rear bearing cap out, clean the packing groves. Install the new packing plugs after you reinstall the rear bearing cap. They should slide in. If they don't fit, clean hole again. If still don't fit, get new ones. Don't use sealer on them, if you oil them use very little. All oil and sealer do is take up space in the hole. Once they are installed, DO NOT cut them flush with the engine block. They should stick out about 1/4 inch. Tighten all bolts and torque, but don't turn the crankshaft for 24 hours to let the sealer between the seal halves set. . Alright guys, ya'll need to chime in here. Did I forget anything????? Good luck if you try this. Don Norris Southeast,NC 53 CJ3B PS Oh yea,, The clutch peadal. Push the clutch in and block it or tie it from underneath. It gives a bit more wiggle room. And take the generator belt off. That way the oil seal in the timing cover can sag to lower the crankshaft. |
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Don Norris Southeast, NC 1953 CJ3B 1959 Jeep Pickup 195? M100 trailer ~~~~~~~~~~~~~~ The trail never ends ~~~~~~~~~~~~~~~ If lovin' Jeeps is wrong, I don't wanta be right. | |
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| cuz | Oct 26 2008, 09:42 PM Post #3 |
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How true that statement can be sometimes! Hello Harold, Jeeps are my hobby but I make a living as a mechanic. I have always preferred to remove the engine, roll it upside down and get a darn good look at everything rather than tough it through several hours of oil dripping in the face just to find out the next day that I have to do it all over again. It only takes 2.5 hours to pull and install the engine. Get her out on the stand. Take a good long look at the back of the engine. Especially at the welsh plug that is hidden behind the flywheel for the cam's rear journal cavity. Make sure this isn't your oil leak source. If it is then pull the flywheel and replace the plug. If not then roll the motor over on the stand and pull the pan. You'll have to do most of Don's steps. However, take all three bearing caps off and using a few pieces of wood as wedges raise the crank and use the wood to support it. Now change the seal per the manual and inspect the condition of all the bearings. This would be a good time to take it another step and pull the rod caps and inspect those bearings. Then even one more step and plasti-gage all of them before finalizing the installation of the rear main seal. Now you would have spent any where from 4 to 7 hours working on your jeep and c confirmed the real source of the oil leak, the condition of the crank and all it's bearings and their clearances. The amount of time was well spent and you can go back together and put her on the road again with a much higher level of confidence in your work.
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| jeeper50 | Aug 30 2011, 11:07 AM Post #4 |
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ol' skool jeeper jeff
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Reviving this post for all of us to reread and learn about rear main leak repairs!!! |
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In the land of the blind... the one eyed man is king Texan at heart, Georgian by paycheck '53 CJ3B, F134, 12v alternator, lockrights, Hot-Spark electronic module,11"self energizing brakes, Belleview winch, Beachwood summertop, OD color, built to honor all Veterans of this great country Kayaks- Hobie Revo 13, Hobie Outback 12' both ready for the salt... | |
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| Don | Aug 30 2011, 06:47 PM Post #5 |
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Jeff,,,,, is there something that you need to tell us about your '53? :rolleyes: Now, just relax,,, take a deep breath. You ARE among friends. We understand these things happen in the best of garages. :ph43r: |
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Don Norris Southeast, NC 1953 CJ3B 1959 Jeep Pickup 195? M100 trailer ~~~~~~~~~~~~~~ The trail never ends ~~~~~~~~~~~~~~~ If lovin' Jeeps is wrong, I don't wanta be right. | |
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| jeeper50 | Aug 31 2011, 07:29 AM Post #6 |
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ol' skool jeeper jeff
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Yes my rear main is leaking currently I should have used the rope seal during overhaul- but noooo I didn't so after two years I'll have to fix it sooner or later |
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In the land of the blind... the one eyed man is king Texan at heart, Georgian by paycheck '53 CJ3B, F134, 12v alternator, lockrights, Hot-Spark electronic module,11"self energizing brakes, Belleview winch, Beachwood summertop, OD color, built to honor all Veterans of this great country Kayaks- Hobie Revo 13, Hobie Outback 12' both ready for the salt... | |
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