Why oh why. Sudden oil pressure drop.

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Quick question before I begin the evaluation. Would it be bad to hook up an air pressure line with say 40 psi to the second port at the back of the motor to test the gauges. In other words, adding air pressure to the system at the port just 6 inches from the other port? This would be just to check the gauges for a few seconds.
I will still pull the distributor and drill the pump counterclockwise with an analog gauge installed before starting the motor.
I also found that the super sniper efi has a setting that can be enabled that if oil pressure drops below XX psi for XX seconds it will shut down ignition. This is a fail safe that I would configure.
 
You don't need a gauge. Take the sender out . Start it with the pedal to the floor and see if the oil hits the hood. LOL
 
I would not put air in there. Chances that the sender port is plugged is zero. Well, LOL pretty small.

1...Hook up manual gauge. You can even use your compression gauge, mine uses common air hose quick connectors that make it easy to adapt
2...If pressure is low I would start by pulling and critically examining the dist, intermediate gear, and look down there with a flashlight and see what. Damaged cam gear, filings, etc.
3...Then pull oil pump and examine, look for busted 'o' rings, etc.
4....It is not that "un" popular to have a cracked pickup tube.
 
I've had a brand new Wix filter on a 2.7 cause this sort of problem (low oil pressure at idle). New Wix fixed it.
I had a bad cam bearing in a 273 cause low oil pressure at idle (missing material from oil hole to air).
Also, assuming hydraulic lifters? Any noise, miss, or other change in the way the engine was running? If it was still running good with no noises, it probably still had oil pressure.
 
Well this is not good. I hooked up an analog gauge and tried with a drill but nothing at all. I tried to burp the oil filter by loosening it, nope. I then removed the pump and it looks good to me. No scratches at all and the O-rings are perfect. This pump is not that old. This is the second time I have lost oil pressure. Last time it was the pickup. Looks like I have to drop the pan and take a look at this pickup. I even made accommodations for the pickup to not seal on the floor of the pan. YET, there were no noises when it was running. The oil was off for maybe 15 seconds or less at most. Only the time to pull up the driveway. 70 feet or so. It might have been ok until idle dropped to 950 idle speed.

Has anyone gone to an external pickup for the oil pump and used a milodon pro touring pan??
Solid flat tappet lifters
 
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I'm thinking that if you cracked another pickup, it must be stressed in some way, and my first thought is "the pan." Look for wear/ rub marks, etc. Keep in mind that skillions of B/RB Mopars ran for decades and I'm joking. I know you realize that
 
67Dart273 said:
I'm thinking that if you cracked another pickup, it must be stressed in some way, and my first thought is "the pan." Look for wear/ rub marks, etc. Keep in mind that skillions of B/RB Mopars ran for decades and I'm joking. I know you realize that
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I did bump it on the rolling jack that crosses the 4 post lift but it does not look bad.
 
Also there's been a couple cases--not necessarily B/RB but Mopar V8--where the pin sheared on the intermediate gear and WAS NOT immediately evident
 
If your oil pickup is sitting on the oil pan floor in any shape or form, as you tighten your pan it puts stress on the oil pump pickup tube.

The weakest part of the pickup tube is at the the threads where it screws into the oil pump. Thread area could have easily split open.
 
George Jets said:
If your oil pickup is sitting on the oil pan floor in any shape or form, as you tighten your pan it puts stress on the oil pump pickup tube.

The weakest part of the pickup tube is at the the threads where it screws into the oil pump. Thread area could have easily split open.
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I don’t know about v8’s but for slant six motors the FSM specifies that the oil pick up is an interference fit to the oil pan floor. My assumption is that mopar v8 engines of the same era would have the same fit requirements for the oil pick up tube.
My ‘engineering’ guess for the interference requirement is so the oil pick up tube is locked in place at both ends. If the tube that is deepest in the pan was allowed to dangle, there is a good probability that at some rpm it would vibrate harmonically and that would surely crack the tube at the fixed end.
 
Kent mosby said:
Good idea, thanks. That would be a stripped gear. I have a bronze gear drive. Hopefully that is not it.
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Bronze gear on a solid flat tappet cam?
I'm not sure that's recommended, I could be wrong but it's not the same billet as the solid roller cam.
My builder told me don't get a bronze gear.
 
Kent mosby said:
Well this is not good. I hooked up an analog gauge and tried with a drill but nothing at all. I tried to burp the oil filter by loosening it, nope. I then removed the pump and it looks good to me. No scratches at all and the O-rings are perfect. This pump is not that old. This is the second time I have lost oil pressure. Last time it was the pickup. Looks like I have to drop the pan and take a look at this pickup. I even made accommodations for the pickup to not seal on the floor of the pan. YET, there were no noises when it was running. The oil was off for maybe 15 seconds or less at most. Only the time to pull up the driveway. 70 feet or so. It might have been ok until idle dropped to 950 idle speed.

Has anyone gone to an external pickup for the oil pump and used a milodon pro touring pan??
Solid flat tappet lifters
Click to expand...
I have external with swinging pick up but a pro-stock pan & run a solid flat tappet
 
MOPARMAGA said:
Bronze gear on a solid flat tappet cam?
I'm not sure that's recommended, I could be wrong but it's not the same billet as the solid roller cam.
My builder told me don't get a bronze gear.
Click to expand...
Check that, a Pinned HD gear Steel not bronze
 
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my68barracuda said:
I don’t know about v8’s but for slant six motors the FSM specifies that the oil pick up is an interference fit to the oil pan floor. My assumption is that mopar v8 engines of the same era would have the same fit requirements for the oil pick up tube.
My ‘engineering’ guess for the interference requirement is so the oil pick up tube is locked in place at both ends. If the tube that is deepest in the pan was allowed to dangle, there is a good probability that at some rpm it would vibrate harmonically and that would surely crack the tube at the fixed end.
Click to expand...
Correct. It is also the same for V8s. The pickup is designed to rest on the bottom of the pan.

Kent, did you closely inspect the female drive hex in the pump and the pump drive shaft as well?
 
Screw it in more this time.

If it swings just past where you need it... take it another turn around to get it there.
Dont use teflon to hold it, just tighten it another turn. I'd use a skin of rtv on the thread just for added seal.
 
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