Oil pump won't prime

[dtaylor73]

As the title says, I can't get my oil pump to prime. The oil pan is full of oil. The pick up is 3/8" off the bottom of the pan and screwed in tight. The pickup and tube was checked for obstructions before being installed. I installed a new timing cover, adaptor, and gears. I put vaseline around the gears to help in the prime and spun it over like a muther with a 1/2" drill on hi speed trying to get that thing to prime. Nothing. Pulled out the relief spring and plunger, cleaned and re-installed. Still nothing. Any ideas before I pull the motor out again?

Thanx.

[tarior]

Fill your oil filter with oil.

[dtaylor73]

OK. I tired it. Filled the filter with oil and spun the drive shat it for about a minute. I still can't get it to prime. Any other ideas out there?

[tufcj]

Are you spinning it the right direction? Try reversing the drill?


Bob
tufcj

[dtaylor73]

Yep. I'm spinning the right direction. Clockwise as you look down at the drive shaft. Any other ideas guys? This thing is inches from getting yanked out again.

[tarior]

Does the motor have oil in it? I know that sounds kinda smart ass, but there was two page thread awhile back wherein one of the listers here couldn't get his rig to start, tried everything, getting frustrated as hell. Turns out there was no gas in it.
Aside from something dumb, it sounds like it's sucking air somewhere.

[dtaylor73]

Ya, the pan was full of oil. It's back on the engine stand with the timing cover off and the cam and oil plugs out of it now. None of the passages are blocked. Pickup is clear. Oil pump and timing cover gaskets were sealed well. Where else should I look where it could be sucking air?

[tarior]

The only thing I can think of is a cracked pickup tube, or blocked inlet.

[Lifted79CJ7]

Have ya tried blowing out the oil passages with compressed air to see if it is clogged?

[dtaylor73]

OK, here's what I checked on oil passages and more info.

Pickup I can easily blow thru. Plug the big end of pickup and blow thru threaded end and nothing comes out and I don't see any cracks so I think the pickup is good. The screen is clean. Pick up to pan clearance was 3/8" plus the thickness of the pan gasket.

Block passage from pickup to timing cover I can clearly see all the way thru it and it's clear. The two oil passages by the lifters I can easily see they are clear. The "Y" at the front of the lifter valley I can see thru both legs and they are clear.

All the passages in the timing cover are clear as are the filter adaptor passages.

The new gears in the new timing cover stuck out past the cover .006" used with a .009 thick gasket. Gear to side of housing clearance less than .0015" using a feeler gauge. The fit between the oil pump drive shaft and housing is excellent.

I had a Fram oil filter on which I had mostly filled with oil on a members suggestion. There was a little over four quarts of 10W40 in the stock pan when I drained it.

I used a Bosch 1/2" drill set on both low and hi speed (3000 rpm max) and let it run trying to get the pump to prime. I had packed the gears with vaseline, so I then pulled the pressure relief plunger out, cleaned and reinstalled it. It appears to be seated. Tried again and zippo.

Is there some trick to priming these things? Maybe I didn't stick enough PB in there. When I tore it apart both holes in the gear cavity were open (not plugged up with PB) so I don't think that could be the problem. In fact, as far as I can tell, the oiling system is good as new. My distributor rotates clockwise looking down at the rotor so that is the direction I spun the priming tool.

I'm out of ideas. When I get another set of gaskets it's goin back together and I'll try again.