20PSI oil pressure in rebuilt motor.
#21
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The short block was assembled by a machine shop. The barbell oil plug is in. Also what would it matter if the can retainer bolts are the right ones? I used two longer bolts on the can sprocket. But they torques down fine and didn't bottom out. And yes I did use the right cam retainer bolts.
And about the oil...that is the exact oil that Texas speed reccomended me to use for break in. They have built quite a few motors so I took their word on it. I don't see how a thicker oil is going to hurt anything. Especially make me have LOWER oil pressure? This thread is bout suggestions on why by pressure is low, not nut swinging on oil types.
And about the oil...that is the exact oil that Texas speed reccomended me to use for break in. They have built quite a few motors so I took their word on it. I don't see how a thicker oil is going to hurt anything. Especially make me have LOWER oil pressure? This thread is bout suggestions on why by pressure is low, not nut swinging on oil types.
Sorry I tried to help you with suggestions.
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#22
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Keep the suggestions coming guys, I really appreciate all the help.
#25
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Looks like the best thing you could do is drain the oil and look at the magnet on the end of the drain plug and possibly cut the oil filter open. You may find your new bearing clearance in there.
O ring would be an easy fix, hope that's it.
O ring would be an easy fix, hope that's it.
#27
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We put in new mains, oil, filter, nothing else. It ran fine ever since.
#28
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I had a cam bearing back out on my new engine and it had the same symptoms. It keep getting lower and lower until the check gauges would come on. It may be worth you time to hook up a mechanical guage to verify its as bad as it looks. Here is a good place to get a reading.
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Last edited by NC98Z; 12-05-2009 at 06:45 PM.
#31
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Well it doesnt drop then pick up when I rev it up....I changed the oil and filter. The oil looked good. Had some small metal shavings on the oil drain plug, not big chunks or anything. Just look like a new motor breaking in.
But the pressure is still low. Im going to hook up a mechanical guage just to rule that out before I tear into the motor again. But I'm leaning towards the o-ring or the pick-up tube not sealing on the pump good, I do have some bubbles on the dipstick so I guess thats a sign of air in the oiling system from something.
But the pressure is still low. Im going to hook up a mechanical guage just to rule that out before I tear into the motor again. But I'm leaning towards the o-ring or the pick-up tube not sealing on the pump good, I do have some bubbles on the dipstick so I guess thats a sign of air in the oiling system from something.
#32
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I think the low oil pressure is due to the clearance on the bearings. The oil you are using is fine for break in and isnt going to hurt the motor one bit. Use a good replacement oil and run it for a bit. 20 psi is not horrible as long as the pressure rises when the rpms increase. let us know what you find next.
#39
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My 163k 6spd LT1 does the same thing. Samething when accleraring fast. it's something about putting a load on the engine that causes the bearing clearences to open up wider.
Is it the stock gauge and sender? Is it the stock oil pan and pick up? You're not running a remote mount oil filter are you? Drain the oil and put on a K&N filter with some 10w30 or something. 20w40 is thick oil. I have seen the best oil pressures with K&N filters over mobile 1, frams, and puralators, on my LT1 and LS1.
Is it the stock gauge and sender? Is it the stock oil pan and pick up? You're not running a remote mount oil filter are you? Drain the oil and put on a K&N filter with some 10w30 or something. 20w40 is thick oil. I have seen the best oil pressures with K&N filters over mobile 1, frams, and puralators, on my LT1 and LS1.
#40
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^^SM is right as I understand it. Then the oil pump spins faster as rpm's rise and OP picks up. I have seen cars run tens of thousnds of miles like this so there is no way to tell.
As long as your oil pressure is decent you should be ok for a while. You prolly know this but a rough rule of thumb is 10psi per 1000 rpms.