Rear main seal leak or oil pan? - Team Camaro Tech
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post #1 of 8 (permalink) Old Jan 9th, 19, 03:08 PM Thread Starter
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Chuck
 
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Rear main seal leak or oil pan?

Hey gang...I just pulled my trans to replace the T/O bearing, and then pulled the clutch and flywheel for further inspection, all was good. I have had a rear engine oil leak for some time, and since it's winter here, I'd like to fix this leak. When I had the flywheel off, the back of the block was bone dry as was the flywheel. Rear of valve covers and intake are dry also. Does that indicate the leak is at the rear pan seal? The "drips" come from the small opening at the bottom of the flywheel shield, but then again, it may be coming from just above and running down that shield. Dare I conclude that if the back of the motor is dry, the pan is the culprit? Ideas?....and Thanks!

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post #2 of 8 (permalink) Old Jan 9th, 19, 03:35 PM
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Re: Rear main seal leak or oil pan?

Are you sure it is motor oil and not gear oil? Did you smell the oil?
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post #3 of 8 (permalink) Old Jan 9th, 19, 05:08 PM
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Re: Rear main seal leak or oil pan?

Doubt it: most likely the valve covers.

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post #4 of 8 (permalink) Old Jan 10th, 19, 03:18 AM
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Re: Rear main seal leak or oil pan?

Could be the very back of the oil pan where it seals around the crank. That is where mine is leaking at the moment

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post #5 of 8 (permalink) Old Jan 10th, 19, 06:06 AM Thread Starter
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Re: Rear main seal leak or oil pan?

Well, like I said, back of engine, upper, is dry. I agree it may be back of pan, but once I'm that far into the job, another hour and the main seal is done. Good thing it's below freezing, nowhere to drive anyway. This all could be a sub-conscious motivation to turn on my heat, and use my new lift, with a new floor, while watching big screen TV....thanks for the suggestions!

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post #6 of 8 (permalink) Old Jan 10th, 19, 06:48 AM
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Re: Rear main seal leak or oil pan?

Check that its not any of the oil pan bolts or the dipstick tube leaking and blowing back. Valve covers or oil sending unit are also strong possibilities. If its the dipstick tube the starter bolts are going to be wet as the oil blows back and runs down the starter. Fuel pump gasket or block off plate gasket are also problem areas.
I'd clean it all up with a degreaser and wipe it down so everything is dry and clean. Add a couple ounces of dye to the oil and let it run for a few minutes then crawl all over it with a black light with al the shop/garage lights turned off.

If it was the rear main or any of the oil galley plugs the entire back of the engine and the flywheel would be wet - trust me.
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post #7 of 8 (permalink) Old Jan 10th, 19, 07:31 AM
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Re: Rear main seal leak or oil pan?

Or use some talcum powder and run it for a bit. It will help identify the leak.

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post #8 of 8 (permalink) Old Jan 10th, 19, 07:38 AM
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Re: Rear main seal leak or oil pan?

Quote:
Originally Posted by travisch View Post
I'd clean it all up with a degreaser and wipe it down so everything is dry and clean. Add a couple ounces of dye to the oil and let it run for a few minutes then crawl all over it with a black light with al the shop/garage lights turned off.

.
^^^^^This.

Oil migrates down to lowest point and/or gets "slung" away (flywheel) making it's source of leak difficult to find.

You are at a point if you replace a non leaking seal and button the car all back up and it still leaks....So if you are not 100% certain you find the leak source,you are gonna have to pull it all apart again.

Been there and done that.....use the dye
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