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Discussion Starter · #1 ·
Quick backstory in case you all don’t know 200,000 on the clock loyal pressure when Hot enough to create a lifter tick every now and then. Just installed a Melling high-volume high flow oil pump and did not change out the spring that comes factory installed. Just putting it all back up got the car primed by disconnecting the injectors and she went right up to 50 psi after cranking for about a minute. Once she fired up oil pressure was about 55 to 60. Car has been running for close to an hour Engine is fully up to temp and oil pressure is steady at about 40 psi. Am I out of the woods or could this still be cam bearings also I am running 1540 full synthetic oil.
 

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Seems that you identified an issue with the oil pump pickup O ring and now have good oil pressure although you are running a heavier weight oil which would increase your pressure compared to 5w-30w, but not sure how much.

Just monitor and see how it holds up. Any leaks with the timing cover, crank seal or oil pan?

Just drive it and see if the lifter tick comes back. Cam bearings can't really be checked without removing the cam and also can't really be replaced (correctly) without removing the engine so I wouldn't worry about that since it's more or less a total rebuild at that point.
 

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Discussion Starter · #3 ·
Seems that you identified an issue with the oil pump pickup O ring and now have good oil pressure although you are running a heavier weight oil which would increase your pressure compared to 5w-30w, but not sure how much.

Just monitor and see how it holds up. Any leaks with the timing cover, crank seal or oil pan?

Just drive it and see if the lifter tick comes back. Cam bearings can't really be checked without removing the cam and also can't really be replaced (correctly) without removing the engine so I wouldn't worry about that since it's more or less a total rebuild at that point.
Even with the heavier oil when I was testing it a few days ago the oil pressure would drop down to 10 to 15 psi. And I’m guessing now that if it was Cam bearings it would still be low oil pressure no matter what. Right ?
 

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Even with the heavier oil when I was testing it a few days ago the oil pressure would drop down to 10 to 15 psi. And I’m guessing now that if it was Cam bearings it would still be low oil pressure no matter what. Right ?
Your assumption seems valid ;)
 

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Discussion Starter · #5 ·
So after bleeding the system and cleaning up tools the lowest the psi dropped was 35 ish with the car only at 550rpm but with 100 +- more rpm and 40/50 psi I’m calling it good 😊
 

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Get rid of that thick oil. If you are hitting over 100 psi. That will blow out oil seals in the LVOM. This is the reason there is a 66 psi relief valve in the oil pan to protect the DOD system. Using thick diesel oil is a stupid overkill. Drain it before you break it.
 

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Discussion Starter · #7 ·
Update to the update lol just fired it up again this morning sitting in the shop. It had a hard time starting but I also had a knock sensor code for bank to yesterday I don’t know if maybe I unplugged it while I drop the pen down or something it’s just going on with a knock sensor I’ll have to figure that one out. But it also had a code this morning for a 5 V reference which I believe Hass to do with the knock sensor code which is kind of odd. After I cleared the code the car ran fantastic and I let it idle till operating temperature again and oil pressure is still at about 40 psi With the engine up to about 200° I’m keeping my fingers crossed
 
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