Amount of oil in engine

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Hi guys
I am curious about how much oil is going through an engine when it is running and how much is in the pan
I dont think I have ever known this
Anyone know?
 
My 2.3L Mazda engine states that the dry engine holds 6.8 quarts and the refill is 6 quarts with filter. I would assume that ~ 6Qs is in the pan and 0.8Q is in the oil galleys and head. Ed
 
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Originally Posted By: Eddie
I would assume that ~ 6Qs is in the pan and 0.8Q is in the oil galleys and head. Ed

When it is running?
 
Depends on the RPM and the engine. One of the HiPo builders for the Ford Modular engine made fibreglass timing and valve covers and watched a DOHC engine running at ~6k RPM force all 6 quarts up to the heads within a few seconds.
 
Lots of variables involved here.

Windage, drainback capabilities, viscosity and longitudinal and lateral forces to name a few.

Our old AMG allowed actual monitoring of its sump's oil level whilst underway as well as when stationary.
Typically had around 2 quarts flailing about 'upstairs' during steady-state highway speeds (as measured from the sensor).

M112dynomodeoillevel.jpg
 
Very little oil is in the galleys and suspended as oil mist. Only a few ounces is in process of dripping back into the engine.

There may be a pint or so in an oil cooling loop. That often doesn't drain during a change.

Many engines do have some splash lubrication, where the crankshaft splashes oil onto the cylinder walls at the very bottom of the stroke. If the oil level is too low this doesn't happen. (If it's too high, the cranks drags through the oil and entrains air.) So you need some significant amount of oil in the system -- it's not as if 90% of the oil is sitting around in the sump solely waiting to be pumped.
 
I mean just in general
My 302 holds 6 qts so how much is up in the motor and how much is in the pan
I dont want the exact amount just a ballpark figure
 
on the Dyno here: Oil flow meter shows 2.5 to 5 gallons per minute oil flow when engine is fully warmed up, and the higher number is at a high rpm (7000) for a race engine. typical v8 engine 2.5 gallons per min. at 4500 rpm. cold flow is very low, maybe a quart a minute at best.
 
Thanks guys but I guess I am not making myself clear
All I want to know is when an engine is running about how much oil is in the pan and how much is circulating
I know there is some oil in the pan at all times but I dont know how much
I thought someone here would have an idea on this by now
 
I will take only a guess here, I belive only a Quart or less is removed from the oil pan and doing its job lubing and cooling upstairs at any given moment on a typical v-6 or v8 engine. (after its warmed up)
 
use the dipstick while your engine is running, and see how much lower it is.

there is your answer
 
There are a lot of factors here.
- return flow from the head(s)
- windage around the crank
- temperature
- viscosity
- rpm
- oilpan design
Generally there are things to awoid...
- letting the crank whip the oil into Cream is the worst and
should be avoided by almost any mean. ( good oilpan, scrapers , windage tray, not to much oil in it etc.)

An Engine running at high speed can easily keep a quart or
two of oil floating around. The worst example ive Heard of was how a Chrysler hemi could have 5 qt´s flying around the crank, the solution was a windage tray and a race pan. The cars came dilivered with the standard pan (had to fit on the car transporter ) and the dealer was supposed to change before delivery.
 
About half a qt on most daily drivers not much more.
Example, take a car with a simple on off switch low oil level monitor, its usually about 1 qt less than full before it comes on.
If more than a qt was in circulation the low oil light would illuminate.

It really has little to do with how much the pump can pump but how large the drain back holes are to keep the oil level in the pan. As long as they at least equal the pump capacity there should be no traffic jam.

Hole size is more important in an OHC engine than a push rod engine (except old air cooled).
The old push rod engine could dump oil back to the pan through the holes in the head for the push rods also.

Figure 4 x 1/2" holes in the head = 2" of drain back capacity, thats the same as roughly a 2" drain pipe. Not much oil is going to hang around.

Simple and non technical half arsed explanation.

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Originally Posted By: bdcardinal
Depends on the RPM and the engine. One of the HiPo builders for the Ford Modular engine made fibreglass timing and valve covers and watched a DOHC engine running at ~6k RPM force all 6 quarts up to the heads within a few seconds.
That can't be. The oil pump pick up screen must be submerged at all times or there will be an oil pressure loss.

Quote:
Many engines do have some splash lubrication, where the crankshaft splashes oil onto the cylinder walls at the very bottom of the stroke.
Does it? Any crankshaft splash into the oil at, say, 5000 rpm would cause immediate foaming of the oil and possibly damage the crankshaft...until the oil was too foamy to either be carried by the crank or too foamy to pump by the oil pump. Yes, oil is flying everywhere, and oil droplets in suspension will be whipped around by the moving parts. But hard parts dipping into the oil laying in the sump? I thought the 1954 pressure lubricated Chevrolet ended that.
 
Honda oil pumps flow between 55 and 65 qt/min at 6k rpm depending on the engine. The return rate capacity must be even higher since redline is much higher in some of the engines. Newer high-performance cars have variable displacement pumps.
 
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