How does the dry stump system work

The oil circuit schematic from the 360 owner’s manual is re-posted in this blog and shows all the routing….

Oil Disareator Refurbishment | Weekend Garage Monkey

The main flow of oil to the high pressure pump is gravity fed but of course the pump also sucks and helps gravity do it’s job.

Over filling the tank can lead to flooding the upper part of the intake manifold with oil. Many have used a turkey baster to extract surplus oil.

 

Your system is not even sort of different. If you can't see the dipstick and tank in that link then you may never understand how it works.

Dry sump is just that, the sump is dry during operation. The tank drains back into the sump when it's not running, which is why the oil check procedure is what it is.

The thing that might confuse you is, unlike a regular wet sump which has 1 oil circuit, the dry sump has 2. One to drain the sump and return it to the tank and one to empty the tank and pump it through the engine.

You can spend plenty of time on google learning what you need to know.

 

If there is no reading on the dipstick when cold why is it necessary to drain oil before removing the disaerator? Looking at the diagram of the system it would appear as if the bottom of the dipstick is below the bottom of the disaerator -- suggesting it can be removed without draining any oil.
Please correct me if I'm making the wrong assumptions.
Alan

 

I wasn't trying to be rude, but there are specifically 13 pictures of the tank/dipstick in that link. That's going to be all from me on this. I hope you find the resolution you seek.

 

The liquid oil leaves the bottom of the oil tank (at zero pressure) and is moved by gravity down to the inlet of the high pressure pump.

As Greg said, the scavenging pumps move more volume than the high pressure pump -- so when the engine is running, there's very little oil down in the bottom sump and most is up in the tank and cooler. The "danger" of being way overfull is that the crankcase ventilation system is also connected to the top of the oil tank (which is an oil vapor area, not an oil liquid area) where the intake system sucks out the oil/crankcase vapors back into the engine intake tract. If this upper area in the oil tank gets too "wet", the intake system will (wrongly) ingest liquid oil.

There is a separate drain plug on the bottom of the oil tank -- but using that would be the hard way to remove just a little oil. 2 possible methods IMO (if you are not way, way overfull), and no need to do either when the oil is hot:

1. Start the engine from cold, and run for maybe a few minutes, turn off engine, and use some sort of suction device to remove oil out the oil filler tube (after such a short run time the oil will not be hot, but the oil tank will be full -- but I note that a Mondial t has sort of a long oil fill tube so probably can't use a kitchen turkey baster directly).

2. Start the engine from cold and run for maybe a few minutes, turn off engine, then remove the engine oil drain plug on the bottom of the engine. Again, the engine oil won't be hot, and only a couple/few quarts should come out (as most of the oil will be up in the tank/cooler). You'll need to replace the bottom drain plug fairly quickly (so be ready with a new sealing washer) as oil will continue to run out thru the clearances in the high pressure pump head and engine bearings.

How overfull are you?

 

A foot or two of hose from the local auto parts store, fuel/oil resistant type slipped "tightly" on the end of the baster extends your reach to fluids. Take the baster with you to the store, be sure it is a tight fit and that it won't come off while sucking up fluids ..... Or you will have a much more serious issue.

 

Yes, that doesn't sound terribly overfull, but you probably need to recalibrate yourself -- on a 300~400 HP engine with no cooler that only holds 5 quarts oil total = way more important to get/keep it near the max mark; on a F that holds a ridiculous amount of oil = halfway between max and min is more than fine

 

Isn't there two quarts "spread" between the Min and Max marks on the dipstick??

That seems to be the case, on my cars.

 

Of course, if you had an air-cooled classic 911, you had an oil pressure AND oil level gauge in the dash as well as a dipstick in the dry sump accumulator tank.

 

Steve
Mine takes 10 quarts as my indie mechanic always gives me the last two quarts out of the case.
Alan

Tom
Thanks for the tip on the hose. I need to pull my disaerator as the paint is peeling and I didn't want to go under the car to drain any oil. Any idea how much to pull to get below the mounting so I don't spill any oil when I remove it?
Alan