CM870 oil pressure low. jakes not working

[jjoshthomas074]

good evening, hope everybody had a great thanksgiving!!!!

Truck 2006 international 9900I cummins cm870 SER#79147134 1.1 mil miles on engine supposedly engine was inframed at one point with no proof. I bought the truck as a project and to go threw it before putting on the road sometime next year. Main problems I'm looking into right now are. Fairly low oil pressure from what I'm reading. cold idle around 30psi, 200F just over 20psi dummy gauge on dash. operating temp, 1500 rpm not much over 33psi. just threw some parts at it considering the unknown maintenance and history of previous work done. still need to get insite up and running, and do the over head set. also noticed the jake brake doesn't work when driving down the road. only engages with a natural rev. not worried about this right now because I don't have insite yet. I pulled the valve cover and did a visual inspection of the head, looks really clean, cams look very good. other then excessive cam bearing wear is their anything else i should and can check easily??? im learning about Cummins as we speak, ive always worked on medium duty power strokes and hydraulic equipment. please feel free to ask any questions!!! Thank You For Your Time

new cummins parts installed
bearing sizes confirmed/ matched
rod bearings
main bearings
thrust bearings
new oil pump, new style not able to shim this style.
pickup tube oring and oil pan gasket
oil filter LF14000-NN
put a semi blend 10w30 and 3 quarts 85-140
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