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lost oil pressure

Old 06-06-2015, 08:58 PM
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Default lost oil pressure

Finally got my truck put back together and it fired up right away but had no oil pressure.. I shut it off and checked oil sending unit plug and pulled off valve cover to make sure it was getting oil and it looked like it was.. Restarted it and it had 40lbs of oil pressure (btr 4 cam sounds nasty when it runs) let it run for about 10min, let it get warm and then shut it off. let it cool down and started it again no oil pressure again.. wtf!! I do have 4 engine codes that are o2 related( bank 1 and 2) im running the front o2s but not the back 2.. This is all on a Texas Speed tune.. What should I do now? Could it be the sending unit or bad oil pump or O ring?? Timing off maybe?? (i turned the motor 7x to make sure the dots lined up every time.. The oil pump is a new high volume pump.. Could the wrong size pushrods be causing this (wouldnt think so) ??? Ive just put new 243 heads on it, btr 4 cam,4.350 pushrods(milled heads) ,trunion kit, ls7 lifters, Long tube headers .. thanks guys
Old 06-06-2015, 09:12 PM
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Could the be due to the fact that i was a ****** dumbass and reused my old cam plate ???
Old 06-06-2015, 09:57 PM
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if you put a new oil pump on then id start with the pick up tube o ring. cam plate wouldnt do anything. wrong size PR would give you a noisy valve train but not low pressure.
Old 06-07-2015, 01:22 PM
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Replaced the o ring today and fired up and satyed at 60psi..
Old 06-07-2015, 03:40 PM
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Pinched o-ring.

Curious, why did you replace the oil pump?
Old 06-07-2015, 06:00 PM
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The truck had 112k on it and I did heads ,cam,lifters ,ls2 timimg chain at once and figured i might as well while i was in there.. Old oil pump was running about 70 just figured might as well..
Old 06-08-2015, 02:31 AM
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While you can reuse the cam plate (but it's risky), I personally wouldn't do it because it protects the lifters and the cam galleries. A leak there can starve the lifters or the cam bearings and WILL cause low oil pressure.

If your seal looked flat on the surface, don't reuse it. There should be a small ridge that runs the circumference that serves as the sealing face of the gasket. If you can't feel it, don't use it.
Old 06-08-2015, 04:38 AM
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Yup yup. What he said ^^^^^^^
Old 06-08-2015, 06:31 PM
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It wasnt flat , i could feel that it raised still.. good to know after the fact ( forgot to look into that one) keepin my fingers crossed.. still at 70lbs driving and 50-55 at idle..
Old 06-08-2015, 06:37 PM
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cut your filter when you dump the oil for the first time to see if it may have gotten the bearings.

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