Can a High Volume oil pump suck the floor up?

[fullmetaljacket]

This question is pertaining to my last about distance from the oil pan floor, so if the oil pump pick up is too close to the oil pan sump floor, can it suck it up to a certain degree?
I ask this because both my old pick up and new one supplied with the deep sump 7 quart pan are hanging a 1/2 inch off the floor whereas 1/4" to 3/8" is acceptable. Why would they both be set up that high?

As far as I know, the engine has always had good oil pressure with the pick up a 1/2" above the floor. This engine was put together by a professional assembler who worked Pro-stock motors. I'm just perplexed that nothing has happened or am I just lucky?
My new pan has small baffle ledges up top and a trap door down by the floor whereas my old steel pan just had baffles up top and no doors.

 

[WS23U1]

Don't know but my wife can.

 

[Curiousyellow71]

This question is pertaining to my last about distance from the oil pan floor, so if the oil pump pick up is to close the oil pan sump floor, can it suck it up to a certain degree?
I ask this because both my old pick up and new one supplied with the deep sump 7 quart pan are hanging a 1/2 inch off the floor whereas 1/4" to 3/8" is acceptable.

I don't see how it could actually pull the pan in. I don't really see where a 1/8" higher is going to affect the pickup other then the pump does not have access to as much oil. We have a pan that was crushed from a wheelie then hitting the brakes. We beat it back out and kept running it. If any pan would get sucked in..it was weakened. Never gave us a issue.

 

[fullmetaljacket]

Oh, and both my old and new pans have strengthening ribs on the bottom.

 

[dvw]

Nope

 

[fullmetaljacket]

Nope

Duly noted.
1/4" to 3/8" off the floor I will have it set for sure. I'll just have to weld a 1/4" section of tube to the existing pick up tube because as it is now, by the time it tightens nicely in the block, the screened pick up box is 1/2" off the floor. Both pick ups oddly enough are short by a 1/4 " or so.
I don't want to give it one less turn into the block with locktite just to meet the optimum level.

 

[Dave6T4]

I would not worry about it. With a 7 qt. pan, you have at least 2 extra qts. of oil in there, so the pickup should always be in oil.

 

[fullmetaljacket]

I would not worry about it. With a 7 qt. pan, you have at least 2 extra qts. of oil in there, so the pickup should always be in oil.

This is what I was thinking, but now that I have my first trap door pan, I don't know how the oil around the pick up may act under hard acceleration. The car carries the wheels up about a whole foot, and then comes down quick, so oil is not always out back.
I mean, with a regular deep sump 7 Qt pan, it seemed to never starve for oil since the engine is still clean and mean.
Very confusing.

 

[HEMI-ITIS]

That is sweet oil pan, With the deep sump and the trap flaps DVW wheelies are safe.

 

[LemonWedge]

Benchracing every topic possible is what this forum is all about. But we just may be overthinking this one a touch, FMJ. It makes sense to me that deeper the pan is, and the more oil it carries, the further away from the bottom of the pan the pickup can safely be. The extra 1/8” also gives more volume of oil waiting “at the mouth” of the pickup.

 

[Geoff 2]

With a deeper pan, you can add more oil [ 7 qts ]. Less risk of the pan being sucked dry. why 1/2" off the floor? My guess is that the extra distance provides smoother flow/less turbulence into the pick up entrance.

 

[j-c-c-62]

I rather doubt "turbulence" (random chaotic flow) with an effectively non compressive liquid with this viscosity is much of a concern in the first place but is possible.

 

[dvw]

In the words of a very smart guy, John Kasse. If there is a line of sight between the crankshaft and the oil pickup you are going to have a problem.
Doug

 

[Kern Dog]

Don't know but my wife can.

Yeah, I heard that too.

Kidding! Hey man, YOU opened the door on that and left it wide open!

 

[moparedtn]

Don't know but my wife can.

 

[fullmetaljacket]

In the words of a very smart guy, John Kasse. If there is a line of sight between the crankshaft and the oil pickup you are going to have a problem.
Doug

Doug. I guess I get what you are saying? I'm going to elongate the pick up tube to reach the desired height of 1/4" off the floor.

 

[Curiousyellow71]

Might want to figure out how much your gaining by lowering it a 1/4". I think likely 1/2 to 3/4 of a pint. Which may not be worth it?
If the pickup is plated, welding makes it blister off. The ones I tweeked I had to use a die grinder to knock off the scale. I'd rather mess with a pickup with no plating. But some time you have no choice.

On a side note. We have done several different brands of engines recently that had rectangular pickups with 7 quart pans. 1/2" seems to be the norm.

 

[fullmetaljacket]

Might want to figure out how much your gaining by lowering it a 1/4". I think likely 1/2 to 3/4 of a pint. Which may not be worth it?
If the pickup is plated welding makes it bloster off. The ones I tweeked I had to use a die grinder to knock off the scale. I'd rather mess with a pickup with no plating. But some time you have no choice.

On a side note. We have done several different brands of engines recently that had rectangular pickups with 7 quart pans. 1/2" seems to be the norm.

CuriousYellow, here's my old pick up with what I guess you're describing as a rectangular pick up.
It sits 1/2" off the floor.
Why I was bringing this whole thing up was that my new 7 qt pan has a trap door whereas my old 7 qt pan did not. The concept of the door is to direct oil to the pick up on acceleration and keep it in the main sump area during deceleration, but will the pump starve if the pick up is too high. Am I brain farting here?

 

[RemCharger]

As far as I know, the engine has always had good oil pressure with the pick up a 1/2" above the floor. This engine was put together by a professional assembler who worked Pro-stock motors. I'm just perplexed that nothing has happened or am I just lucky?

Sounds like you're praising the builder and questioning his intelligence and ability all at the same time? I'd leave it where it was, you're nit picking over 1/8 ".

 

[j-c-c-62]

CuriousYellow, here's my old pick up with what I guess you're describing as a rectangular pick up.
It sits 1/2" off the floor.
Why I was bringing this whole thing up was that my new 7 qt pan has a trap door whereas my old 7 qt pan did not. The concept of the door is to direct oil to the pick up on acceleration and keep it in the main sump area during deceleration, but will the pump starve if the pick up is too high. Am I brain farting here?

View attachment 1818917

Trying to understand the PU pictured above. What exactly does that ring in the screen indicate directly below the tube?