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Replaced RMS, instantly leaked

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Old Mar 17, 2016 | 11:17 PM
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Angry Replaced RMS, instantly leaked

So I just got finished putting my car back together (had to pull the motor to change the rear main seal) and boom, an instant leak coming from where the bellhousing connects to the motor. I did everything by the book, got a Fel-pro seal kit, greased the inside of the seal and the crank, used the Alignit tool, torqued everything to spec, and it still leaked. Do you think it was a trash seal? Should I not have greased it (it came greased on a white installation tool)? I was thinking that it might take a few minutes to get a good seal with the grease still in there but I'm not sure. Any ideas?
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Old Mar 18, 2016 | 08:59 AM
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A new seal should not leak if it was a good seal, undamaged, and it was installed correctly. The inside of the seal should not have been lubricated before installation and only a light coat of oil should be used on the outside of the seal. Did you have anything else apart when the seal was replaced that could be leaking where you can't actually see it?
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Old Mar 18, 2016 | 09:02 AM
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Originally Posted by unit
A new seal should not leak if it was a good seal, undamaged, and it was installed correctly. The inside of the seal should not have been lubricated before installation and only a light coat of oil should be used on the outside of the seal. Did you have anything else apart when the seal was replaced that could be leaking where you can't actually see it?
I had the motor on a jack, I dropped the oil pan and replaced that gasket, I saw no visible leaks coming from the oil pressure sender or around the intake. The leak is very bad, about a half-quart per minute when the motor is running. What else is there to leak?
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Old Mar 18, 2016 | 09:51 AM
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Any chance that you have the seal in backwards? There is some fine print on the seal that says "This side out". It's easy to get backwards and it will leak.
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Old Mar 18, 2016 | 10:51 AM
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Originally Posted by unit
Any chance that you have the seal in backwards? There is some fine print on the seal that says "This side out". It's easy to get backwards and it will leak.
I triple checked the writing
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Old Mar 18, 2016 | 10:51 AM
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Did you keep white disk inside it as you pushed it over the crank? You should have. This keeps the lips of the seal oriented in the right direction as it's slid over the crank. As previously stated, the seal can only go on one way. There should have been some words embossed on side of the seal that said "This side out".

Since I had the rear cover off as well when I changed mine I took some really fine emery cloth to the crank to clean up all the junk that was building up a groove where where the old seal ran. The new seal (in my case a GM seal), was a revised piece and didn't ride the same spot on the crank as the old one I removed.
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Old Mar 18, 2016 | 10:53 AM
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Originally Posted by RebelExtrm02
Did you keep white disk inside it as you pushed it over the crank? You should have. This keeps the lips of the seal oriented in the right direction as it's slid over the crank. As previously stated, the seal can only go on one way. There should have been some words embossed on side of the seal that said "This side out".

Since I had the rear cover off as well when I changed mine I took some really fine emery cloth to the crank to clean up all the junk that was building up a groove where where the old seal ran. The new seal (in my case a GM seal), was a revised piece and didn't ride the same spot on the crank as the old one I removed.
Yes, we kept the white alignment tool on while installing it. We also used the aftermarket tool to hammer it in place
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Old Mar 18, 2016 | 10:58 AM
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Did you remove the rear cover for any reason? Did you remove the oil barbel in the back of the block? When you reinstalled the flywheel did you use a threadlocker or thread sealant? Did you make sure the oil pan stayed flush with the back of the block so it didn't get cracked when tightening the bell housing bolts? Sorry, just trying to think of all the common ways, other than the seal, that oil could be escaping the motor.

I'd say if you didn't touch anything other than the seal that goes inside the rear cover against the crank and sealed the crank threads and didn't crack the pan then it almost has to be a defective seal. Either way you have to take it back apart. Once you get back inside the back of the block you might be able see where it all came from.
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Old Mar 18, 2016 | 03:02 PM
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I removed the rear cover and changed the seal because it was destroyed. I used the Alignit tool to center the cover back on the block. I removed the oil barbel and replaced it. Yes, the oil pan looked like it was flush when mounting the bellhousing. I did not use threadlocker or thread sealant when I installed the flywheel. I could understand a defective seal causing a small drip, but surely not a large leak like this
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Old Mar 18, 2016 | 04:41 PM
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The holes that the flywheel to crankshaft bolts go into are not blind and do enter the inner cavity of the motor where oil is. Oil can and does seep by the threads of those bolts if a sealant or threadlocker isn't used. I don't think it would amount to a flow of oil though, you would most likely notice it as a drip later on and a slipping clutch (from contamination). Other than that I'm out of ideas at this point.
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Old Mar 18, 2016 | 04:47 PM
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Originally Posted by RebelExtrm02
The holes that the flywheel to crankshaft bolts go into are not blind and do enter the inner cavity of the motor where oil is. Oil can and does seep by the threads of those bolts if a sealant or threadlocker isn't used. I don't think it would amount to a flow of oil though, you would most likely notice it as a drip later on and a slipping clutch (from contamination). Other than that I'm out of ideas at this point.
Do you think it could be the oil pressure sensor behind the intake manifold? That's my final hope before I drop the transmission again
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Old Mar 18, 2016 | 05:17 PM
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Do you think it could be the oil pressure sensor behind the intake manifold? That's my final hope before I drop the transmission again

Absolutely! Bump it, and it'll crack.....
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