1997 5.7 rear main seal

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Hi all, having another problem with my engine I just put in my boat. The engine was sitting about 2 years in a shed wrapped up in a tarp before I put in my boat. Well the rear main seal was leaking when I got it running on the water. It leaks all the way around the bellhousing and sprayed out the vent port by the starter ont the starboard side bilge. Well I pulled the motor a couple weeks ago and replaced the rear main. I noticed it had a very slight surface rust on the crank (which I thing may have been the cause for the leak). So I cleaned the crank with a fine bristled wire wheel to where it felt very smooth. I reinstalled the rear main. And got it all back together. After 2 trips with no problem on the third trip out I ran it a bit harder and what do you know? It's leaking the same! Spraying oil onto the starboard bilge.

My question is should I have polished the crank to a mirror finish before re installing the seal? I checked the valve covers and I have already pulled the intake mainofold to replace the intake gaskets at the same time I replaced the rear main. So I know it's not the back of the intake. Thanks for any help!
 

alldodge

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Did the back of the motor and the flywheel look all oily when replacing the seal?
Remember what the cam seal plugs looked like?
Have you check the oil temp sender behind the distributor?
If there was a groove and some heavy pitting then you might need a speedy sleeve
 
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It was just a slight surface rust, I did take a picture of the back of the motor. Unfortunately it was after I had cleaned and wiped all the oil off and removed the rear main
 

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alldodge

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The pic doesn't give any signs. Find any leaks from other locations?
 

Drcoffee

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in cars, a product called AT205 helps reseal rotational seals like the front and rear main seal. worth a try, especially on an older engine
 
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