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Obviously it starts in the sump, gets picked up by the pump, and probably sent through the filter, but where does it go from there? Any super secret BMW diagrams floating around out there?
 

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It goes from the sump to the pump.
All pumped oil goes from the block to the oil filter and back to the block.
A small amount is returned to the pump to lube the pump bearings on the scavenge side.
The rest flows up at the front of the block and through the oil cooler.
The oil exits the cooler into the main gallery which runs front to back in the floor of the valley.
From the front of the gallery it supplies the cam chain guide that does the tensioning.
Also from the front it supplies both heads.
Along the gallery it supplies each crank main bearing.
From the back of the gallery it tees off and supplies the two piston squirter galleries which run along the sides of the block.

The supply to the heads goes across the front of the heads and supplies two galleries that run front to back that supply the the bearings and lifters on each cam.
The stamped steel galleries that run across the top of each cam are also supplied to lube the cam lobes and generally splash oil around.
The galleries across the front of both heads supply the between-cam chain tensioners, and the supply to the VANOS units.
The gallery across the front of the RHS head supplies the main chain tensioner.
 

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Question concerning oil scavenge system and oil solenoids in the oil pan:

Usually S62 takes about 6.8 to 7 litres of oil with filter. If you have empty oil solenoids in the oil pan after some more invasive repair, it takes about 1 litre more. What actually happens to that 1 litre of oil? I mean is that 1 litre "passively" trapped somewhere in the block or solenoids waiting 0.9g cornering force to be exceeded (solenoid activation limit)? Or is there constant oil flow through the solenoids so that there is effectively about 8 litres of oil circulating in the system even the solenoids are inactive?

Just curious...
 

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Thanks to 68FB for somehow managing to obtain a copy of the original BMW designer's engineering diagram of the S62 engine oil flow paths. Mightily impressed with their technical prowess! :)
 
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Regarding the question about held-up oil, each head drains into the large oval holes in each side of the block and down through the large galleries cast into the block seen in this pic to the sump:

210520121237.jpg

The oil comes out into the sump through the large round holes shown below (5 on one side and 4 on the other due to cylinder offset, I guess):

honedblock3.jpg

One of the large round holes on each side of the block mates up to the high g section of the solenoid valve (SV). The rest of the holes drain into the sump. The dedicated high g drain shows up here, second from the back on each side.

200520121213.jpg

With the windage trays removed in the pic below, you can see how the normal oil drain from the heads ends up in the upper sump and flows "downhill" to the two small catchment sumps at the rear of the engine. Splash oil from the crank bearings and piston squirters also drains into these two sumps.

The two scavenge pumps built into the main oil pump continuously suck the oil out of the small sumps through the cross-over tubes and pump it into the lower oil sump.

The oil draining from the heads down the two dedicated high-g drain ports flows through passages cast into the upper sump to the closed port of each SV so it is trapped and backfills up to the heads.

OILPAN004.jpg

The cast-in passages for the high g oil pathway to the SV's show in this pic (the outer ones). The inner "passages" are just to provide clearance for the oil tubes. The SV mounting locations are also show.

IMG_20111005_211630.jpg

When running high g's (>0.9g according to the training manual), oil piles up in outer side (relative to cornering direction) of the outer head and in the outer side of the upper sump. One SV opens so that one scavenge pump is now dedicated to sucking oil down from the outer head. The other pump continues to empty the upper sump but now, courtesy of the cross-over tube, it's just sucking from the small sump on the outer side of the upper sump.

Anyway, to answer the question asked about oil held up in the dedicated, and normally closed, head drain passages, I have to think BMW was smart enough to pulse the SV's open once in a while to allow held-up oil to drain. When I get my car out in the Spring, maybe I'll check.
 

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I've sometimes wondered about this as well. When changing the oil, I'm not so sure that the oil in the high G drains is drained into the sump(s).

When I changed my rod bearings, I left it a day or two before I drained the oil. When I removed the solenoids I'm sure I filled a 1l container for each side, so 2l in total was held behind the solenoids. I reckon that this shows that the solenoids seal pretty well and aren't cycled at shutdown.

This means that a normal oil change will leave about 2l of the old oil remaining in the engine. I don't know whether cycling the ignition key would cause the solenoids to open (enough to drain the chambers?) but it would be nice to be able to remove more of the oil, or at least have much less than 2l remaining. I've not noticed or read any instruction from anyone regarding a method of emptying these drains/cycling the solenoids, or to have the ignition 'on' whilst draining the oil...

Also, the secondary (ie higher, rear-most) sump holds quite a bit of oil. When this was removed, I had a lot come out of it, even with the solenoids removed. However, do bear in mind that I had the front of the car up in the air by about 3feet, so this might be expected :) With the car on a flat surface it's likely that this would drain into the lower oilpan.

Currently the only way I can see to empty the drains is to remove the solenoids, but I don't think they were made with removing them often in mind (and you would need three new 'O' rings per solenoid, all different sizes, six in all if you wanted to do it properly). I suppose it would be possible to make up a little device to connect to the solenoids that would open them, they only have a pretty ordinary two pin 'injector' type connector.

Am I correct in thinking that the solenoids have three working positions? One is closed (no oil flow), other is fully open (so in high G, feeding direct to the scavenge pump). Is the this another position where the oil drains as usual to the upper sump, through (or past) the solenoid 'valve'? I remember wondering about this whilst I had things in bits, but I didn't want to mess around too much with them as I didn't want to break them! If there is a third, drain position, then it would be possible to activate or move the solenoid to this position to empty the oil.

Thinking further about it, if this is so, the normal 'ignition on' key position should do it, as you would think that the car would be started with 0 lateral G, thus a standard draining of the heads direct to the sump would be best. This would also be true for normal driving conditions, the oil draining directly into the sump through the drain tubes and the solenoid valves.

It might be worth it for us to drain the oil with the ignition 'on' to see if we get more oil from the engine? This is the simplest way to see if this is true I suppose.
 

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I agree the SV's aren't cycled at shutdown. A lot drained out of mine when I did the chain guides. But, like I said above, I have to assume BMW pulses them occasionally while driving to drain them so they refill with fresh oil to ensure we don't all have the original 15 year old fill trapped in there.

You can cycle the SV's with DIS, although IIRC, DIS just snaps them open and closed so you can check for the click, so it may take many cycles.

With only a supply and ground wire, the SV's will only have two positions: the normal deenergized one that the spring drives the spool to with no power supplied, which allows the scavenge pumps to suck continuously from the two small sumps at the back of the upper sump, and the other position the spool moves to when the DME energizes the coil, which connects the scavenge pump to the dedicated head drain passage.

IMG_0268x.JPG
 

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It goes from the sump to the pump.
All pumped oil goes from the block to the oil filter and back to the block.
A small amount is returned to the pump to lube the pump bearings on the scavenge side.
The rest flows up at the front of the block and through the oil cooler.
The oil exits the cooler into the main gallery which runs front to back in the floor of the valley.
From the front of the gallery it supplies the cam chain guide that does the tensioning.
Also from the front it supplies both heads.
Along the gallery it supplies each crank main bearing.
From the back of the gallery it tees off and supplies the two piston squirter galleries which run along the sides of the block.

The supply to the heads goes across the front of the heads and supplies two galleries that run front to back that supply the the bearings and lifters on each cam.
The stamped steel galleries that run across the top of each cam are also supplied to lube the cam lobes and generally splash oil around.
The galleries across the front of both heads supply the between-cam chain tensioners, and the supply to the VANOS units.
The gallery across the front of the RHS head supplies the main chain tensioner.

Forgot a couple of paths:

Out of the RMS, thru' the bell housing and onto the floor.
Out of the valve cover gaskets, down the sides of the block and onto the floor.
 

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Is that the rare S62 training manual? How many pages is there in the S62-related section?
 

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Is that the rare S62 training manual? How many pages is there in the S62-related section?
Yes it is the technical training manual for BMW M and covers the S62. There are 25 pages on the S62 specifically, 21 pages on the E39 M5 and 44 pages on the MS S52 engine management system.

Wish I knew photoshop so I could have made it a bit more convincing...
 
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