Oil leak at bottom of Alternator E90 320i 2006 N46 Engine

ShakeelAwan · 02-03-2018, 05:41 PM

Hi all,
The battery warning light came up in morning but went away after few minutes.
The alternator looked fine from top but oil is there at bottom. I can't even see much from passenger's side. Looks like right under it. So put my mobile phone in and made a video.
The valve cover and filter housing gaskets look okay.
Kindly see the video and help me identify source of this oil leak.

https://youtu.be/AqbS_IvjnCA

Thank you so much for your time.

BravoJohny33 · 02-03-2018, 05:47 PM

oil filter housing gasket?

ShakeelAwan · 02-03-2018, 08:06 PM

Thanks Johny.
I had removed acoustic cover hoping it would be oil filter housing gasket as it was fairly easy DIY as compared to one on N46 engine @ E46.
However, there was just a pencil thickness and 4 inch oil area, it was dryed and doesn't look like it got till end and also couldn't see any fresh oil. I also checked the area around this gasket with my hand. Looks clean, no oily residue. May be previous owner changed it or it may have occurred during oil filter change. I just bought it last week; thinking all my life BMW would be the best. Only realizing later it's seals and rubber quality.
Lastly, there is no oil at top of alternator.
I am just new to BMW and have no idea what is next below the oil filter housing gasket and that too towards cabin side; so as oil is leaking at generator bottom and cabin side area.

maxoutput · 02-03-2018, 08:21 PM

Theres not a lot over that side that could cause oil to collect theare, oil filter gasket or oil cooler gasket on the side of the filter housing would be prime suspects.
The inlet manifold sits over the top and unless oil is leaking from there I can’t see how any oil would migrate there from anywhere else. Have you checked the CCV pipework hasn’t split anywhere?

ShakeelAwan · 02-03-2018, 08:53 PM

^Thanks Mate. Both side and bottom gasket on oil filter housing look okay.
I will check the CCV hoses. Besides the car does smoke a little puff or so when I blip throttle after few minutes idle. So thinking to replace CCV. In this regard, I don't find much info on net for N46 engine @ E90. It looks somewhat different to most N46 engine @ E46 videos. I will appreciate any reference in this regard.

maxoutput · 02-04-2018, 12:56 AM

The valve stem seals go hard on the n46 , this causes a puff of blue smoke after the engine has idled a while then revved. A faulty CCV can also cause this but in my experience it’s usually the valve stem seals.

ShakeelAwan · 02-04-2018, 04:25 AM

Regarding CCV vs Valve stem seals; I have heard that if upon blip smoke is too much, it is valve stem seals, if little it's CCV and also that untill one replace's CCV, weakest seals around engine will keep leaking. Further that valve stem seals will smoke at startup too. Mine doesn't smoke at startup or even during normal start at traffic lights. Only smokes little after hard revvs in idle, and that too at 1st couple of blips. Lastly I was more concerned about smoke colour it was bluish rather pure white, and smell similar to blowby. so piston rings...But mechanics say, if it is piston rings, Car will always smoke. So what is causing this smoke. Also where can I get any good write-up on CCV for N46@E90 320i.

02-03-2018, 05:41 PM	#1
ShakeelAwan Registered 1 Rep 4 Posts Drives: BMW 320i 2006 Join Date: Jan 2018 Location: Sydney, Australia iTrader: (0)	Oil leak at bottom of Alternator E90 320i 2006 N46 Engine Hi all, The battery warning light came up in morning but went away after few minutes. The alternator looked fine from top but oil is there at bottom. I can't even see much from passenger's side. Looks like right under it. So put my mobile phone in and made a video. The valve cover and filter housing gaskets look okay. Kindly see the video and help me identify source of this oil leak. https://youtu.be/AqbS_IvjnCA Thank you so much for your time.
	Appreciate 0 Tweet Quote

02-03-2018, 05:47 PM	#2
BravoJohny33 Major 310 Rep 1,016 Posts Drives: BMW 2010 Join Date: Mar 2016 Location: GA iTrader: (0)	oil filter housing gasket?
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02-03-2018, 08:06 PM	#3
ShakeelAwan Registered 1 Rep 4 Posts Drives: BMW 320i 2006 Join Date: Jan 2018 Location: Sydney, Australia iTrader: (0)	Thanks Johny. I had removed acoustic cover hoping it would be oil filter housing gasket as it was fairly easy DIY as compared to one on N46 engine @ E46. However, there was just a pencil thickness and 4 inch oil area, it was dryed and doesn't look like it got till end and also couldn't see any fresh oil. I also checked the area around this gasket with my hand. Looks clean, no oily residue. May be previous owner changed it or it may have occurred during oil filter change. I just bought it last week; thinking all my life BMW would be the best. Only realizing later it's seals and rubber quality. Lastly, there is no oil at top of alternator. I am just new to BMW and have no idea what is next below the oil filter housing gasket and that too towards cabin side; so as oil is leaking at generator bottom and cabin side area.
	Appreciate 0 Quote

02-03-2018, 08:21 PM	#4
maxoutput Private First Class 33 Rep 182 Posts Drives: E90 2005 Join Date: Sep 2016 Location: U.K. iTrader: (0)	Theres not a lot over that side that could cause oil to collect theare, oil filter gasket or oil cooler gasket on the side of the filter housing would be prime suspects. The inlet manifold sits over the top and unless oil is leaking from there I can’t see how any oil would migrate there from anywhere else. Have you checked the CCV pipework hasn’t split anywhere?
	Appreciate 0 Quote

02-03-2018, 08:53 PM	#5
ShakeelAwan Registered 1 Rep 4 Posts Drives: BMW 320i 2006 Join Date: Jan 2018 Location: Sydney, Australia iTrader: (0)	^Thanks Mate. Both side and bottom gasket on oil filter housing look okay. I will check the CCV hoses. Besides the car does smoke a little puff or so when I blip throttle after few minutes idle. So thinking to replace CCV. In this regard, I don't find much info on net for N46 engine @ E90. It looks somewhat different to most N46 engine @ E46 videos. I will appreciate any reference in this regard.
	Appreciate 0 Quote

02-04-2018, 12:56 AM	#6
maxoutput Private First Class 33 Rep 182 Posts Drives: E90 2005 Join Date: Sep 2016 Location: U.K. iTrader: (0)	The valve stem seals go hard on the n46 , this causes a puff of blue smoke after the engine has idled a while then revved. A faulty CCV can also cause this but in my experience it’s usually the valve stem seals.
	Appreciate 0 Quote

02-04-2018, 04:25 AM	#7
ShakeelAwan Registered 1 Rep 4 Posts Drives: BMW 320i 2006 Join Date: Jan 2018 Location: Sydney, Australia iTrader: (0)	Regarding CCV vs Valve stem seals; I have heard that if upon blip smoke is too much, it is valve stem seals, if little it's CCV and also that untill one replace's CCV, weakest seals around engine will keep leaking. Further that valve stem seals will smoke at startup too. Mine doesn't smoke at startup or even during normal start at traffic lights. Only smokes little after hard revvs in idle, and that too at 1st couple of blips. Lastly I was more concerned about smoke colour it was bluish rather pure white, and smell similar to blowby. so piston rings...But mechanics say, if it is piston rings, Car will always smoke. So what is causing this smoke. Also where can I get any good write-up on CCV for N46@E90 320i.
	Appreciate 0 Quote