Burning oil and oil in coolant expansion tank

jmiske4 · 10-26-2020, 11:32 AM

I have a 2008 bmw 335i convertible n54 engine I drove my car to school a couple days ago and burned a lot of oil about enough to bring up the check oil light in my car. I go to start it this morning and it brought up the check coolant light and checked the coolant expansion tank and there was no visible coolant and I looked down inside the tank and found a dark chocolate like substance I'm thinking it is oil but I'm not sure how to go about it because Im going to do a coolant flush and see what it might be and don't want to start the car without knowing what is wrong

m_thompson · 10-27-2020, 08:59 AM

Probably needs the oil filter housing gasket replaced.

e91Owner · 10-27-2020, 04:51 PM

Yep. Sounds like your OFHG is probably gone. You can probably see oil/salt residue pooling below the intake manifold.

jmiske4 · 10-28-2020, 11:13 PM

I had a dealer replace the ofhg before I posted this and I feel it might be residue oil but still so confused on the coolant

Peckarami · 10-29-2020, 02:28 AM

The OFHG has both oil and coolant passages. If the gasket between the oil and coolant has failed, that could be the source of the 'gunk' in the expansion tank.

I literally just replaced the oil cooler on my other halfs astra last week, same symptoms as you (oil in coolant) replace the cooler and no more oil in coolant.

I would have expected them to do a coolant flush if they replaced the OFHG though?

e91Owner · 10-29-2020, 05:12 PM

Quote:

Originally Posted by jmiske4

I had a dealer replace the ofhg before I posted this and I feel it might be residue oil but still so confused on the coolant

If the OFHG (which is a very thin gasket) goes, oil has the potential to be mixed with coolant since the gasket is both for the oil and the coolant going through the oil filter housing. Just watch a video on how to change it and it'll all make sense.

jmiske4 · 10-31-2020, 04:35 PM

I figured it out I'll need to do a coolant flush and throw some distilled water in it first then fill it with coolant after but thank you to all the people who commented and helped me understand if I should do anything different please let me know

10-26-2020, 11:32 AM	#1
jmiske4 New Member 0 Rep 8 Posts Drives: 2008 BMW 335i Join Date: Oct 2020 Location: pittsburgh pa iTrader: (0)	Burning oil and oil in coolant expansion tank I have a 2008 bmw 335i convertible n54 engine I drove my car to school a couple days ago and burned a lot of oil about enough to bring up the check oil light in my car. I go to start it this morning and it brought up the check coolant light and checked the coolant expansion tank and there was no visible coolant and I looked down inside the tank and found a dark chocolate like substance I'm thinking it is oil but I'm not sure how to go about it because Im going to do a coolant flush and see what it might be and don't want to start the car without knowing what is wrong __________________ JM
	Appreciate 0 Tweet Quote

10-27-2020, 08:59 AM	#2
m_thompson Major 133 Rep 1,416 Posts Drives: M-Sport 128i, 328xi, 3.0CS Join Date: Jun 2008 Location: New England, USA iTrader: (0) Garage List 2009 128i [0.00] 1972 3.0CS [10.00]	Probably needs the oil filter housing gasket replaced. __________________ '09 128i - Black Sapphire Metallic\Coral Red\Glacier Silver\N51 DISA\6MT\Navigation\Premium\M-Sport\Heated seats\Xenon\Headlights\iPod\Smartphone\Euro Delivery
	Appreciate 0 Quote

10-27-2020, 04:51 PM	#3
e91Owner e91Owner 425 Rep 1,129 Posts Drives: 2011 e91 & 2010 e60 Join Date: Mar 2018 Location: Out of the Office iTrader: (0)	Yep. Sounds like your OFHG is probably gone. You can probably see oil/salt residue pooling below the intake manifold.
	Appreciate 0 Quote

10-28-2020, 11:13 PM	#4
jmiske4 New Member 0 Rep 8 Posts Drives: 2008 BMW 335i Join Date: Oct 2020 Location: pittsburgh pa iTrader: (0)	I had a dealer replace the ofhg before I posted this and I feel it might be residue oil but still so confused on the coolant __________________ JM
	Appreciate 0 Quote

10-29-2020, 02:28 AM	#5
Peckarami New Member 2 Rep 24 Posts Drives: BMW E92 335i Join Date: Jun 2020 Location: Ipswich iTrader: (0)	The OFHG has both oil and coolant passages. If the gasket between the oil and coolant has failed, that could be the source of the 'gunk' in the expansion tank. I literally just replaced the oil cooler on my other halfs astra last week, same symptoms as you (oil in coolant) replace the cooler and no more oil in coolant. I would have expected them to do a coolant flush if they replaced the OFHG though?
	Appreciate 0 Quote

10-31-2020, 04:35 PM	#7
jmiske4 New Member 0 Rep 8 Posts Drives: 2008 BMW 335i Join Date: Oct 2020 Location: pittsburgh pa iTrader: (0)	I figured it out I'll need to do a coolant flush and throw some distilled water in it first then fill it with coolant after but thank you to all the people who commented and helped me understand if I should do anything different please let me know __________________ JM
	Appreciate 0 Quote