oil pump???

[klaussk]

I have a 1985 Chevy k10 stepside shortbed with a 305 and a 700r4 tranny with 96,000 miles on it. Its running low oil pressure around 30. Is that the right oil pressure. I never drove a 305 but every other small block Chevy Ive dealt with ran at least 40 to 45.  My dad has a 95 Tahoe with about 100,000 miles and it started to run around 30 psi of oil pressure. So we changed the oil pump and it was fine. Do you guys think my oil pump might be worn out? I think it is. Also any idea how hard it will be to change it. I don't have anywhere to pull the motor. My dad had to disconnect his engine from the mounts and tilt iy to remove the oil pan from his Tahoe. I don't think ill have to do that with this truck.

[ohio hab]

Is the 30lbs of pressure at idle and after the engine is warmed up? If so the pressure is fine. The general rule is 10lbs of pressure for every 1000 rpm's. The weight of oil also has a slight bearing. I have had sbc's with 10lbs at idle and they lasted. If the engine was mine I would just drive it. Oil pressure deals with bearing clearances inside the engine. SBC's oil pumps rarely get weak, they either pump oil, or they don't.

[klaussk]

Yeah its about 30lbs warmed up at idle. Doesnt seem to go any higher with more rpm, but im not sure. ill have to drive it again and check.

[bake74]

     Also check that your gauge is not giving you a false reading.  Other than that the pick up screen on the oil pump itself could be dirty, I don't think it is unless the oil gets dirty alot, but you never know.