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| | | | Joined: Jul 2008 Posts: 111 Shop Shark | | Shop Shark Joined: Jul 2008 Posts: 111 | (1957 235cui)
2day I noticed a drip from the pan that covers the flywheel. This is the pan which has a small hole in its center.
Is this an indication that my rear main seal is shot?
If not, from where else can the oil come from?
THANKS! | | | | | Joined: Nov 2001 Posts: 1,517 'Bolter | | 'Bolter Joined: Nov 2001 Posts: 1,517 | Thats an indication that the rear main oil seal is shot.
The hole is there for exactly that purpose.
Good luck,
Marty | | | | | Joined: Dec 2005 Posts: 547 'Bolter | | 'Bolter Joined: Dec 2005 Posts: 547 | Can you tell if it is coming from inside the flywheel pan? My egin has a leak in the front, but from driving the oil is blown all over the rear of the engine too, so there is oil on my flywheel pan aswell. If that is the only place you have oil dripping from then good bet it is the rear main seal.
58' 3200 235 3-speed/OD
| | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | It is likely the rear main seal but like Mr. Fiend says sometimes other leaks can run out of there. Check the valve cover gasket & the side cover. Pull the flywheel cover & check the oil pan gasket.
They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | If your rear main is leaking a lot, you will be able to see oil on the flywheel with the cover off. | | | | | Joined: Sep 2003 Posts: 1,820 Shop Shark | | Shop Shark Joined: Sep 2003 Posts: 1,820 | 216-235-261 engines sit lower in the back than the front causing any oil escaping from the engine or engine parts to run to the back lowest point. That point is the flywheel cover. Before I went down to your FLAPS to buy a new rear main seal, I would check and be sure no oil is coming from the back of the valve cover toward the back and at the back, check the lower bottom rear corner of the side cover, check the bolts which hold the coil bracket in place. This is one spot more oil than you think comes from. Of course, you want to check the oil pan bolts and the timing cover bolts. Make sure no oil is coming from these spots. If there is still oil coming to the flywheel cover, you may have a problem. A little oil is expected IMHO, but a bunch is not. As said, also check the flywheel. If there is oil on it, you have aproblem, but if it is dry, your oil acculmantions are coming from some of these other places. Best of luck hunting down you oil leaks. 
"Truckin' Around .......... Since 1937!" My name is Joe and I am addicted to Classic Country Music. I just can't hep myself.Operators are standing by to take your calls! Now cruising in the Passing Lane | | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | Just to emphasize what was said above, I chased an oil leak all last season that put oil on the bottom of the pan, the entire length, oil on the head/block interface, oil on the back of front plate, oil on the bottom of the starter and oil on the front of the bell housing. It turned out that the fuel pump was leaking from the pivot pin below my sight line and only at speed. The fan air blew it all over the engine. | | | | | Joined: Jul 2008 Posts: 111 Shop Shark | | Shop Shark Joined: Jul 2008 Posts: 111 | thanks for al the advice, guys.
I will pull the flywheel cover and see. I dont think its the rear main seal. the engine was just rebuilt. It may be blowing to the back as stated above. I did notice some oil coming from the lower drivers side oil lines that go into the block. It may be coming from there and blowing back to the pan. At least I hope its coming from there. Its a much easier fix than the rear main seal. | | |
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