Looking for some advice- weird looking oil

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I'm confused, I'll admit I know little about that particular motor, but how is a serpentine belt failure going to put metal in the oil?
It gets chewed into pieces and those pieces block the screen of the oil pickup tube causing oil starvation. Some pieces can get into the timing chain. Typical BITOG mantra of "oil is cheaper than replacing leaky gaskets." doesn't fly with this engine family.


 
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It gets chewed into pieces and those pieces block the screen of the oil pickup tube causing oil starvation. Some pieces can get into the timing chain.


I actually have no words. How did they manage to actually invent a failure mode that actually drags pieces from outside to inside the engine....causing engine failure no less. Over something as simple as an accessory belt.
 
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I actually have no words. How did they manage to actually invent a failure mode that actually drags pieces from outside to inside the engine....causing engine failure no less. Over something as simple as an accessory belt.
Less pulleys? Electric water pumps and electric steering don't need pulleys to function. There's an aftermarket solution, but the real solution is to not let chronic oil leaks fester.
 
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I'm confused, I'll admit I know little about that particular motor, but how is a serpentine belt failure going to put metal in the oil?
Gets sucked in through front crank seal, pieces of belt block oil passages and starve engine of oil. Common victim are rod bearings.
 
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Less pulleys? Electric water pumps and electric steering don't need pulleys to function. There's an aftermarket solution, but the real solution is to not let chronic oil leaks fester.
Well this one doesn’t have electric steering but yeah, no water pump pulley.
Not letting oil leaks forever and changing thing in time and no problem. I do have steel plate on mine just bcs. I track car so who knows.
 
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Well this one doesn’t have electric steering but yeah, no water pump pulley.
Not letting oil leaks forever and changing thing in time and no problem. I do have steel plate on mine just bcs. I track car so who knows.
I was wondering if someone made a guard for that. Of course fixing the leak is the best, but be nice to have extra protection just in case the belt fails for some other reason.
 
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I was wondering if someone made a guard for that. Of course fixing the leak is the best, but be nice to have extra protection just in case the belt fails for some other reason.
Yeah. Very simple solution.
I have different one, but this is how it looks:
 

ktish

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OP, any update?
Yes, but no. Decided based on feedback here to drain this fill at 500 miles and send it off for UOA. Then switch to M1 Euro for the superior cleaning abilities. Unfortunately, the starter on the car died and I just got it repaired so I haven't been putting miles on. Hopefully will be able to put some miles on it this coming weekend.
 

ktish

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Update: Sent in the oil for UOA and just got the results back. Have been driving the car in the mean time, probably close to 2k miles since the original purchase and over 1k since the oil was sent off for the UOA. No real changes to note in the behavior of the car. Attached is the UOA. So I'm not entirely sure what was going on as there was no metal in the oil filter(s) that I've cut open from the car.
Yeah. Very simple solution.
I have different one, but this is how it looks:

There was a good discussion about the bolts used by these kits on e90post where some users were expressing concern that the included bolts (non aluminum) wouldn't play nice with the magnesium/aluminum block on these n52's. Would be curious to hear what everyone here has to say on the subject.
 

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Keep driving and do UOA at 5k.
I personally didn’t have any issues with those bolts. Don’t forget that that is just shield.
But, if you are not comfortable with it, make sure you have OE belt or Continental one, OE tensioner or INA tensioner, change belt every 60k and don’t allow oil from leaking OFHG to get onto belt or tensioner.
Only reason this is an issue bcs. people neglect OFHG leak or never change belt.
 
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This engine was prone to ticking due to leak down from the valves. Also, there was an issue where some of the head bolts weren't torqued or over torqued. I can't remember. The bolts were aluminium TTY.

BMW addressed the ticking with a revised cylinder head. You may want to have someone check the head bolts.

The block has a magnesium core and rest is aluminium.
 
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BMW E90 electric water pumps suffer frequent failure between 60k miles and 100k miles. What happens is the motor overheats as there is no insulating member in the electric motor to pump shaft. So, the heat from the pump gets transferred to the motor. If you change the pump you need to change the thermostat as the thermostat has to come out when changing the pump. Why did BMW do this? To increase the car's mileage by 0.01mpg!
 
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BMW E90 electric water pumps suffer frequent failure between 60k miles and 100k miles. What happens is the motor overheats as there is no insulating member in the electric motor to pump shaft. So, the heat from the pump gets transferred to the motor. If you change the pump you need to change the thermostat as the thermostat has to come out when changing the pump. Why did BMW do this? To increase the car's mileage by 0.01mpg!
No BMW did it for numerous reasons:
1. It decreases load on engine.
2. It is more effective cooling.
3. You can manipulate cooling. There 4 cooling plans in E90 where DME adjusts cooling based on the load. In 335, 135 you can actually manipulate cooling with coding if vehicle is serious track car.

Other manufacturers have their water pumps failing at that mileage too. BMW electric water pump on N51/52/53 lasts as long as regular ones on naturally aspirated engines of other manufacturers. Difference is that DME can notice failing electric pump earlier than regular.
 
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BMW E90 electric water pumps suffer frequent failure between 60k miles and 100k miles. What happens is the motor overheats as there is no insulating member in the electric motor to pump shaft. So, the heat from the pump gets transferred to the motor. If you change the pump you need to change the thermostat as the thermostat has to come out when changing the pump. Why did BMW do this? To increase the car's mileage by 0.01mpg!
It actually frees up some horsepower and allows for better FE and performance. The pumps have been upgraded a couple of times.
 
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sometimes engine condensation in the sump creates an oil mix which can make it clowdy.

If this is the case, then short drive with cold engine is the main culprit.

In worse cases, it will form a sticky yellow deposit "mayonaise" inside the oil filler cap.

If the cloud is more like sediment then the UOA should help explain
 
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