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Melling O-Ring Assist

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Old Dec 13, 2017 | 12:20 AM
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This weekend I turned the engine over for the first time and did not have any oil pressure. We took the oil filter off to see if any oil would come out the filter relocation hoses. My friend and I came to the conclusion that I didn't use the correct o-ring. Tonight I pulled the pump to verify and I need more experienced verification. The pump was completely dry inside with oil not going beyond the seal.

The swap kit I'm using comes with the pickup pictured below along with the green o-ring not in the bag. The Pump came with these two and it looks like I should of used the black ring. Can anyone just verify this is correct? I'm also curious why the o-ring type is so crucial and caused the oil no pressure. The engine is a LM7 just in case for reference. Thanks for helping, I want to make sure I don't have to do this again.

Attached Thumbnails Melling O-Ring Assist-20171213_010655.jpg   Melling O-Ring Assist-20171213_001455.jpg   Melling O-Ring Assist-20171213_003056.jpg   Melling O-Ring Assist-20171213_003107.jpg   Melling O-Ring Assist-img_20171014_215255_878.jpg  

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Old Dec 13, 2017 | 10:52 AM
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Usually, if the pickup tube has a groove pressed into its circumference where the O-ring goes, use the fatter of then two. If NO groove, the thinner one goes on.
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Old Dec 13, 2017 | 11:34 AM
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You asked why the o ring is so crucial, because if you use the wrong size (too small) the pump will suck air instead of oil, too big and it'll likely pinch the o ring and again suck air.
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Old Dec 13, 2017 | 11:36 AM
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In your picture that pick up tube is tapered. The instructions say use the green o ring on the tapered pipe.
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Old Dec 13, 2017 | 12:37 PM
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What pickup tube / oil pan are you using? There are two O-ring sizes and it depends on the pickup tube you use.
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Old Dec 13, 2017 | 02:52 PM
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The kit came with the green ring already on the pickup tube. When comparing the pickup tube to the ones in the video it looks like mine is a lot more subtle which leads me to believe it should be black. Attached is the best picture of the pan and pickup tube I have. Thanks for the help.
Attached Thumbnails Melling O-Ring Assist-fb_img_1513192673165.jpg  
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Old Dec 13, 2017 | 02:59 PM
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Use the green one, and put some oil on the oring before you install the pickup tube. Also you should shim your oil pump, and put some assembly lube on the impeller.
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Old Dec 13, 2017 | 04:07 PM
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Originally Posted by I_clutch
The kit came with the green ring already on the pickup tube. When comparing the pickup tube to the ones in the video it looks like mine is a lot more subtle which leads me to believe it should be black. Attached is the best picture of the pan and pickup tube I have. Thanks for the help.
Dude.

And you might as well have posted a pic of a potato.

We need to know the brand of the kit, and which one it is. Or a close pic of YOUR pickup tube. Help us help you man.
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