Battery Tender recommendations

[mr2mike]

Yeah, here's what condensation and oil does when you don't get the vehicle hot enough.

[bjstare]

^thats exactly what I was thinking about when I said to never start it unless you intend to drive. If you don’t get enough heat in the engine and fluids, condensation builds up and fucks ‘er. And obvi, the battery drain thing, but that’s less consequential.

[Flexray]

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Yeah, here's what condensation and oil does when you don't get the vehicle hot enough.

What type of failure would this condensation build up cause? If my N52 also has this milky substance what type of repairs can I be expecting?

[mr2mike]

Honestly, I think it's the ccv vent system that gets plugged with this gunk then causes issues.
Replace or at least inspect your whole ccv/pcv valve system and lines. A few hundred bucks in parts.
The ones on here were definitely a reduced inside diameter with the sludge.

[Flexray]

Isn't the whole purpose of crankcase ventilation to remove blow by so sludge doesn't build up?
I bet that engine had a broken ventilation hose, and the sludge build up is from a malfunctioning system and not from being started randomly.

2500 rpm, unloaded for 15 min will get you 100C oil temp, a open thermostat, and more amps thrown at the battery.

[ExtraSlow]

What are we even arguing about here?

[killramos]

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What are we even arguing about here?

I think it’s the starting your parked car up once a month thing

[ExtraSlow]

Fucks sakes I'm sure I said something smart about that previously, but there's no way I'm finding it, and I'm not sober enough to write it again. But tldr, don't.

[mr2mike]

I don't disagree with you. It's not from running for 10min in winter. Bmw is known for plugged up ccv systems.

But was showing what you'll get if you do run intermittently in winter for your summer ride. Not worth it. That sludge will go elsewhere.

[Flexray]

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I don't disagree with you. It's not from running for 10min in winter. Bmw is known for plugged up ccv systems.

But was showing what you'll get if you do run intermittently in winter for your summer ride. Not worth it. That sludge will go elsewhere.

I'm not following you here. How will running the engine for a few minutes cause sludge?

This is my understanding of how crankcase ventilation systems works. When a cylinder hits the power stoke and the air/fuel mixture is burned, a byproduct of combustion is water vapor. Some of this exhaust leaks past the piston rings and into the crankcase. While the blow by-gasses (exhaust gases) travel around the rings and through the crankcase and it mixes with oil. This happens no matter what temperature the engine is at.

The crankcase is under negative pressure from a intake manifold vacuum source. The crankcase vapors get sucked through a port in the block or valve cover, sometimes through a oil/vapor separator, then through a orifice or diaphragm valve and into the intake manifold to be burned.

The crankcase is under a vacuum whenever the engine is running, there is a constant flow of fresh filtered metered air that travels through the crankcase. Even when you shut off the engine the crankcase will only hold a few liters of fairly fresh air that could maybe condense.

When a ventilation hose breaks, the intake manifold vacuum source will suck unmetered fresh air from outside the engine instead of sucking out the crankcase. This causes the blowby gasses to not be removed from the crankcase, that will condense and sludge up and set lean air fuel ratio trouble codes. The diaphragm in the pcv metering valve can also tear, applying full intake manifold vacuum to the crankcase. The engine will make a weird weezing sound as air gets sucked past seals and gaskets. It's not just BMW, all modern day engines fail like this.

I think being worried about condensation is stupid.

[mr2mike]

Keep starting your parked car in winter. I don't care.
I don't and my oil is cleaner when I drain it before spring start up.

Literally showing you proof that sludge happens. Short drives and the motor temps are not to operating temp by the time this bmw gets parked for the day.
So really, this situation is even better than idling your summer supercar for 30min in your garage and it still causes oil condensation sludge.
Does it cause unrepairable damage? Probably not. But if your summer super car is tuned up, over time you probably don't want this plugging up your lines.

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2500 rpm, unloaded for 15 min will get you 100C oil temp, a open thermostat, and more amps thrown at the battery.

In a heated garage maybe.
-30 parked outside. 100% does not or my oil temp sensors are all garbage.

[Flexray]

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Keep starting your parked car in winter. I don't care.
I don't and my oil is cleaner when I drain it before spring start up.

Literally showing you proof that sludge happens. Short drives and the motor temps are not to operating temp by the time this bmw gets parked for the day.
So really, this situation is even better than idling your summer supercar for 30min in your garage and it still causes oil condensation sludge.
Does it cause unrepairable damage? Probably not. But if your summer super car is tuned up, over time you probably don't want this plugging up your lines.

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In a heated garage maybe.
-30 parked outside. 100% does not or my oil temp sensors are all garbage.

The valve cover you posted, that engine has a problem.And I don't think it's from short tripping.