Possible oil leak

bimmerlove335 · 05-14-2017, 12:05 AM

Hi all,

I recently had my oil filter housing gasket replaced. The oil level was dropping pretty quick before that. Now it seems to lose a quart about every thousand miles. I haven't seen any drops of oil on the ground under it or any serious oil in the engine bay. The only oil I've seen is behind the alternator kind of below the intake, but not sure if thats residual or not. The valve cover gasket definitely looks like it isn't leaking and I know the front main seal is good. What do you think it could be?

Thanks, Nate

juld0zer · 05-14-2017, 08:12 AM

Man that must've been a huge leak to have it lose that much oil that quickly..
Most of the soiling behind the alternator and on that slope on the block is just residue - should've cleaned it when you had the housing off

bimmerlove335 · 05-15-2017, 01:16 PM

It was all over he front of the engine, but I cleaned it off and it hasn't been oily since replacing the gasket. That's why I'm wondering what the problem is now.

juld0zer · 05-16-2017, 10:21 AM

Did you change the belt?
Did you replace the two small orings for the engine oil cooler lines?

Joebie · 05-16-2017, 10:30 AM

How many miles on your car? If its losing a quart every 1k miles it would definitely be seen dripping on the ground.

I suspect that if you don't see any drips, that the oil is instead being burnt. I think turbo seals might be the culprit.

Here's a test: Have a friend follow you as you drive. Engine brake for 1/8 of a mile, and then floor it. Ask your buddy to look for a cloud of blue smoke from the exhaust.

bimmerlove335 · 05-18-2017, 01:03 PM

Engine doesn't seem to smoke at all. Turbo's hold good boost. I notice a few small drips under my car but they look like they've been there a while. The front of the engine is completely clean. Front main bearing is obviously not leaking either. It could be a pan or rear main seal, maybe I'll drive up on ramps soon and take a look

bimmerlove335 · 06-05-2017, 09:29 PM

Update: Turbo seals definitely appear to be good. I do notice consistent drips under the car. When I put it up on ramps I noticed that there is oil leaking somewhere behind the AC pump/ alternator area. I'm confident it is not the OFHG. I don't believe it is the valve cover gasket because that area is dry. It seems to be lower down than the valve cover.. What do you think it could be?

ssdara · 06-08-2017, 11:41 PM

Mileage? Use a towel or tissue around your valve cover. You cant see some angles of it. High mileage could be bad oil pan leak around 100-120k miles

I would make sure the bolts on ofgh are at least hand tight too (depending on your strength u may need torque wrench and set proper torque)

bimmerlove335 · 06-10-2017, 02:16 PM

Ok. Will check that out. It kinda seems like a pan leak at this point, just wondering how the oil got above up close to the AC pump. I guess valve cover is still a possibility. Is there any way the PCV system could be leaking somewhere on the intake side of the engine?

Thanks for the replies!

05-14-2017, 12:05 AM	#1
bimmerlove335 Private 52 Rep 82 Posts Drives: Black '09 335i Join Date: Apr 2017 Location: PNW iTrader: (1)	Possible oil leak Hi all, I recently had my oil filter housing gasket replaced. The oil level was dropping pretty quick before that. Now it seems to lose a quart about every thousand miles. I haven't seen any drops of oil on the ground under it or any serious oil in the engine bay. The only oil I've seen is behind the alternator kind of below the intake, but not sure if thats residual or not. The valve cover gasket definitely looks like it isn't leaking and I know the front main seal is good. What do you think it could be? Thanks, Nate
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05-14-2017, 08:12 AM	#2
juld0zer Lieutenant Colonel 480 Rep 1,600 Posts Drives: Prev 135i 7DCT, Now 130i 6sp Join Date: Jul 2016 Location: 2153 iTrader: (0)	Man that must've been a huge leak to have it lose that much oil that quickly.. Most of the soiling behind the alternator and on that slope on the block is just residue - should've cleaned it when you had the housing off
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05-15-2017, 01:16 PM	#3
bimmerlove335 Private 52 Rep 82 Posts Drives: Black '09 335i Join Date: Apr 2017 Location: PNW iTrader: (1)	It was all over he front of the engine, but I cleaned it off and it hasn't been oily since replacing the gasket. That's why I'm wondering what the problem is now.
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05-16-2017, 10:21 AM	#4
juld0zer Lieutenant Colonel 480 Rep 1,600 Posts Drives: Prev 135i 7DCT, Now 130i 6sp Join Date: Jul 2016 Location: 2153 iTrader: (0)	Did you change the belt? Did you replace the two small orings for the engine oil cooler lines?
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05-16-2017, 10:30 AM	#5
Joebie Grandmaster 779 Rep 803 Posts Drives: 2018 ///M2 6MT Join Date: Dec 2014 Location: St. Louis iTrader: (0)	How many miles on your car? If its losing a quart every 1k miles it would definitely be seen dripping on the ground. I suspect that if you don't see any drips, that the oil is instead being burnt. I think turbo seals might be the culprit. Here's a test: Have a friend follow you as you drive. Engine brake for 1/8 of a mile, and then floor it. Ask your buddy to look for a cloud of blue smoke from the exhaust. __________________ Daily - 2018 Alpinweiß ///M2 6MT Exec Rain/Snow/Winter - 2011 328i 6MT Sedan - Black on Black, Sport Package Sold, But Not Forgotten - 2009 135i 6MT - Black on Black, M-sport, JB4
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05-18-2017, 01:03 PM	#6
bimmerlove335 Private 52 Rep 82 Posts Drives: Black '09 335i Join Date: Apr 2017 Location: PNW iTrader: (1)	Engine doesn't seem to smoke at all. Turbo's hold good boost. I notice a few small drips under my car but they look like they've been there a while. The front of the engine is completely clean. Front main bearing is obviously not leaking either. It could be a pan or rear main seal, maybe I'll drive up on ramps soon and take a look
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06-05-2017, 09:29 PM	#7
bimmerlove335 Private 52 Rep 82 Posts Drives: Black '09 335i Join Date: Apr 2017 Location: PNW iTrader: (1)	Update: Turbo seals definitely appear to be good. I do notice consistent drips under the car. When I put it up on ramps I noticed that there is oil leaking somewhere behind the AC pump/ alternator area. I'm confident it is not the OFHG. I don't believe it is the valve cover gasket because that area is dry. It seems to be lower down than the valve cover.. What do you think it could be?
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06-08-2017, 11:41 PM	#8
ssdara Second Lieutenant 65 Rep 285 Posts Drives: 2007 335i Sedan Join Date: Aug 2010 Location: Baton Rouge, LA iTrader: (1)	Mileage? Use a towel or tissue around your valve cover. You cant see some angles of it. High mileage could be bad oil pan leak around 100-120k miles I would make sure the bolts on ofgh are at least hand tight too (depending on your strength u may need torque wrench and set proper torque)
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06-10-2017, 02:16 PM	#9
bimmerlove335 Private 52 Rep 82 Posts Drives: Black '09 335i Join Date: Apr 2017 Location: PNW iTrader: (1)	Ok. Will check that out. It kinda seems like a pan leak at this point, just wondering how the oil got above up close to the AC pump. I guess valve cover is still a possibility. Is there any way the PCV system could be leaking somewhere on the intake side of the engine? Thanks for the replies!
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