M30 oil filter housing and check valves

dang

dang

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Can someone explain to me when and how the different M30 motors and oil filter housing use check valves for the oil? There's different oil filter configurations and block designs but I'm confused about which setup to use on a M30B35 out of a '92. I have a filter housing from the '69 motor and Mike Gobel offered a top bolt style housing.

How do the different designs work?
 
Quick comments...

The early filter was too damn close to the hot lead on the back of the alternator.
When techs got lazy and “forgot” to disconnect the battery and the rubber boot on the positive terminal was rotten or missing- all hell broke loose.

The m30b35 housing has a notorious dry start problem where oil flows back into the block.

The best answer for me is the euro bottom drain on the oil cooler m30 version-
Easy to drain, holds it oil, farther from the alternator.
 
sfdon said:
Quick comments...

The early filter was too damn close to the hot lead on the back of the alternator.
When techs got lazy and “forgot” to disconnect the battery and the rubber boot on the positive terminal was rotten or missing- all hell broke loose.

The m30b35 housing has a notorious dry start problem where oil flows back into the block.

The best answer for me is the euro bottom drain on the oil cooler m30 version-
Easy to drain, holds it oil, farther from the alternator.
Click to expand...
I've already plugged the oil passage in the block and shortened the terminal on the alternator when it was on the old block. So if I use the older bottom bolt unit or the newer top bolt unit it will function the same as far as oil drain down? My understanding was the dry start problem was primarily with the filter housing with the top mounted cartridge, so when the check valve goes bad the filter has to fill up before oil pressure will build. With bottom cartridge units and a plugged oil passage mod, is there a check valve in the system?
 
There is a pressure bypass for when filter gets clogged looks like a check valve.
If oil is draining up you have bigger problems. That's why we keep the rubber side down when we drive hard.
:)
 
Markos said:
I don’t want to get too technical for you Don, but I am pretty certain that in Australia oil does drain up.
Click to expand...

I think thats when fluids drain backwards in the lower hemisphere- called the Corona effect?
 
So it doesn't matter if I use an early or late bottom filter housing (bottom vs top bolt), other than convenience.
 
From my previous life...


Oil pressure slow to appear on startup


Oil pressure slow to appear on startup

I put a 91 M30B35 in my Bavaria recently and the oil pressure is very slow to catch on a cold start. I used the original oil pump and added the pickup and pan that fit the E3. Once the pressure has been established it works very well, 70# while cruising down the road at 3000 rpm. I changed...
e9coupe.com e9coupe.com
 
Mike Goble said:
From my previous life...


Oil pressure slow to appear on startup


Oil pressure slow to appear on startup

I put a 91 M30B35 in my Bavaria recently and the oil pressure is very slow to catch on a cold start. I used the original oil pump and added the pickup and pan that fit the E3. Once the pressure has been established it works very well, 70# while cruising down the road at 3000 rpm. I changed...
e9coupe.com e9coupe.com
Click to expand...
Good info. My small brain is still having trouble understanding how it all works. You would think that a filter canister hanging down would always have oil in it. The oil either gets siphoned out somehow or is pushed out and not replaced when the motor stops, which would explain the check valve I guess. Or...

Either way I suppose the way to go is to use Mike's filter housing. :)
 
Dan- you want the setup from a e28 535i.
Not the original and not the b35.
 
sfdon said:
Dan- you want the setup from a e28 535i.
Not the original and not the b35.
Click to expand...


So the one on the right is what we want, right?

Came off an E12.

oil-filter-holder.jpg
 
Coriolis acceleration, involves a double dot product with vectors etc. Basically unsolvable equation but it's real. I still recall deriving it in my fluid dynamics class. Ahhh, to only know as much as I have forgotten.
 
I’m trying to make sense of this thread. I see above that an e12 filter canister is recommended over the stock e9 one but then there’s the linked thread which recommends the later e28 canister over an earlier one. And also that oil won’t drain up.
Is there a definitive reason not to use your factory e9 canister other than convenience?
@dang - did you find a solution?
 
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