No Oil pressure. Help needed?

[photon]

Have an old 70 charger with a 383.  Have most likely only put 100-150 miles on the car since I bought it.  Working thought all the bugs.  Fixed an ignition problem  and now noticed I am getting no oil pressure on the aftermarket gauges mounted under the dash.  Looked at the oil on the stick, it was full and clean. Took the oil filter off and cranked on the motor and not much spit out.  What came out was real dark and nasty.  The filter paper was nasty as well.  was told to take the pump off and blow air through  and maybe the screen inside was clogged.  The car sat for along time before I purhcased it.  The car only ran for about 30 seconds without oil pressure.  My other mopars gain pressure in this time period.  Any ideas?  During my 100-150 miles of driving I honestly do not remember looking at the oil pressure gauge.  Was focused on some other issues since fixed.  I have had the heads off and checked due to an overheating issue in the radiator.  Any ideas would be greatly appreciated.  Thanks Dodgecharger.com.

[Challenger340]

I dunno about blowing back through the pickup with the pump off, if it is plugged, blowing the crud back in, to get sucked up again later sounds foolish ?

Gonna be messy, but get the Filter off again, Crank it awhile and see if it WILL or WON'T pickup and squirt a good stream of Oil where the Filter should be ?
If Not,
well I'm guessing there may be an Oil Pan removal in your future ?

[elacruze]

I'd pull the distributor and be sure the pump drive shaft hasn't twisted off or stripped out. Then you can use a priming rod to spin the pump, see what comes then.

[flyinlow]

Start the engine with the oil preasure sender removed. Oil should be shooting out within a few seconds of starting.

Doubt you could drive 150 miles without oil preasure and not know it. ( you know,  knock-knock-knock-clank, damn, towtruck)

Drain the oil, take pipe cleaners or a piece of vacuum line and feel around in the bottom of the oilpan for sludge buildup. The oil pick up is not far from the drain hole. The bottom of the pickup is about 1/4 inch above the floor of the pan.

They do sell engine flush.

[68 RT]

Try hooking up another gage first.

[photon]

Finally got some oil pressure.  I know that there was no way that I drove that thing without any pressure.  Didn't get much oil to come out with the filter off and cranking the motor.  Ended up maybe not doing the correct thing by forcing air through the pickup and trying to listen for bubbling in the pan.  Didn't hear to much on that.  Took the plug out and forced air and oil came gushing out of the pan.  Pulled the hose off the oil gage and then oil finally came out of that after cranking the motor.  I didn't come out before.  The pump drive shaft was fine.  The oil pump was a little nasty.  Ended up putting a wire through the plug hole and didn't find any sludge.  I am just going to drive the thing and keep a real close eye on my oil pressure.  This is all a little out of my scope of knowledge but the car sat for along time over the winter and years before I purchased it.  A buddy of mine mentioned something about how the car may have lost some vac um from sitting.  I really did not follow what he was saying because I was just happy to have oil pressure back.  Thanks again dodgecharger.com