Oil Pressure Problems
My 77 j20 with a 360 is having oil pressure issues. Truck was sitting for 1 or more years without running but it had oil in it and everything wasn't seized. It is a pretty worn out motor but it started right up when i got it home but it ran with a bad miss but that has been resolved. I changed the oil with 10w-30 and a wix filter. My gauge says about 60 psi of oil pressure cold and around 40 hot, but just the other day, the pressure went from 60 to exactly zero really slowly, and then about 5 min later at idle it rose slowly to 60 again and stayed there. My oil is full on the dipstick. The outside of the oil pump is not wet but its just covered in years of oily build up on it and I cant really find a really noticable leak that would create a huge problem. What could be the cause of this wierd loss of oil pressure?
PS: I have already changed my pressure sender because the old one got full of gunk when I put risilone through the motor before I did my oil change.
76' J20: 401/th-400/quad