Priming An Engine

BBShark

Garage Monkey
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I am priming an engine and have been running the pump with a drill at 2500rpm (turning clockwise) for a long time, maybe 20 minutes. All I get is a little oil weeping out of the hole in the rockers.

I see videos where hole is shooting out when priming. Whats the problem?
 
I usually watch the gage, and keep at 40 or 50 psi for a while.

What does the gage read?
 
I don't have a gauge on it right now. Been investigating where the pressure sender should be and it looks like it's supposed to go in the port at the front of the engine on left hand side (BBC).
 
Any chance you have a reservoir system you are trying to fill/pressurize?
Just thinking of challenges I hope to face this winter (or next).

Cheers - Jim
 
I'm not saying this note pertains to your question, I am only relaying my (only) oiling problems in the past.

Years ago a buddy of mine had finished assembling his 454, and I got a call from him that he couldn't get any oil pressure while priming it, and wanted my opinion. I dropped by his house and looked at the situation. I noticed he wasn't seeing much "torque" on the drill motor while spinning the primer (an old modified distributor I loaned him). He was pretty bummed out, thinking that the oil pump or pickup tube was faulty, and he was going to have to pull the engine out again. I suggested that he take the filter off and run the primer a moment to confirm if there was any actual problem with the pump/pickup. Nothing happened for a moment, and then oil gushed out. He apparently had a good size air bubble in the pump that prevented it from priming/pumping. We put the filter back on, and the system primed as expected afterward.

Second story: A couple years later, while autocrossing my '84, I made a hard stop into a "garage stop" at the end of the run. The oil pressure went to zero, and stayed there. I shut the engine off for a moment, and then restarted. Still no oil pressure. Shit. I took a chance that the problem was a similar air bubble (and not a part failure in the engine), and reached under the car and unscrewed the oil filter. Cranked the engine until oil squirted out, and then replaced the filter. Started the engine and had oil pressure. I ordered an Accusump cylinder for it the next week, as I didn't want to risk encountering this issue again, particularly if I was at an actual track day.

Those are just my experiences with the oiling system. Let us know what you find out on your issue there.
 
I have been trying to figure out the correct location for an oil sending unit (for a BBC). When looking I found someone who had the same problem loosing oil pressure after hard braking.

There is a 3/8" pipe thread above the oil filter and that is apparently the bypass for the filter. The consensus seems to be not to use that. Also 70's BBC oil senders have a 1/8" or 1/4" thread. There is a 1/8 port above and to the left of the oil filter (next to the 3/8 port). Some say to use the 1/4" port at the front of the engine, on the left side right above the oil pan. This is apparently the furthest point from the oil pump and the best place to get an accurate pressure.
 
I rotated the engine in 15-20 degree increments then run the drill and did this until I had turned at least two revolutions. I also cranked the engine with the starter while running the drill.

I'm getting decent oil at the cylinders closest to the pump but not much at the front of the engine. Also getting good pressure.

I'm going to consider this done and put the distributor in.
 
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