It can cause problems when raining even when the car is parked. The water drops into the spark plug wells. Don't forget to put it back before the winter.

 

The coils have a built-in gasket that seals to the cylinder head. There should be no problems with water intrusion unless one does something silly like pressure-wash the engine.

 

Makes no difference. First off, the amount of heat it traps is negligible. Second, oil and water temperatures are thermostatically controlled by the DME--it won't run any cooler, because the DME will simply adjust the thermostats to bring the temperature back up to the target range. Finally, you're wrong about its purpose, which is purely cosmetic.

Modern engines are swathed in a mass of plumbing and control harnesses, and stuffed into cramped engine bays. Rather than expend time, money and precious under-hood space to make all of the oily bits aesthetically pleasing (as in the old days), the modern solution is to just slap a lid over them.

 

Makes no difference. First off, the amount of heat it traps is negligible. Second, oil and water temperatures are thermostatically controlled by the DME--it won't run any cooler, because the DME will simply adjust the thermostats to bring the temperature back up to the target range. Finally, you're wrong about its purpose, which is cosmetic.

Thanks for answering my question. I don't believe your answers are 100% correct, and I welcome debate -- after all, I didn't design the thing.

Firstly, although temperatures are thermostatically controlled, when it's 105F outside and I'm in slow moving traffic, the thermostatic control has its limits. At the end of the day, engine heat must be radiated out of the engine by airflow over the engine, oil cooler and radiator. The electronic controls cannot change this. I found one day that I could not get my AC to blow cold air; I believe this was because the computers shut down the compressor to aid in engine cooling. The AC came back later and worked just fine. The N55 engine manual states that this is exactly what happens when engine temp gets too high.

Secondly, you can see that underneath the plastic engine cover, there is a fairly thick layer of rubber. This clearly isn't cosmetic, it is there either to reduce engine noise or else to provide thermal insulation. This thermal insulation can help capture heat over the valve train during cold starts in cooler weather. This would reduce engine wear; it makes sense. But in very hot weather, the rubber will clearly trap heat and prevent cool airflow over the top of the engine (unless there is some scoop I don't know about which forces cool air between the engine and engine cover).

That's my thinking, and I welcome your opinions on the subject.

 

Was your car actually running hotter than normal prior to removing the cover?

My experience has been that these cars are very good at regulating their temperature.

We have run hard in Death Valley numerous times, uphill in very high temps and I have never seen it increase by more than 10 degrees (260F with N54,and 250F with the N55) and never had any overheating issues.

How the N58 will fare will have to wait till next spring, but I am confident it will be fine.


jummo

 

Was your car actually running hotter than normal prior to removing the cover?

My experience has been that these cars are very good at regulating their temperature.

We have run hard in Death Valley numerous times, uphill in very high temps and I have never seen it increase by more than 10 degrees (260F with N54,and 250F with the N55) and never had any overheating issues.

How the N58 will fare will have to wait till next spring, but I am confident it will be fine.

jummo

I just did a run from Indio to Phoenix today, 105 outside no temp increase noted.

Sent from my SM-G930T using Bimmerfest mobile app

 

With the hot summer temperatures, and no rain whatsoever here in California, I removed the plastic engine cover and put it in my garage. My thinking is that this will help the engine run a little cooler, and I don't think there is any benefit to the cover other than some sound insulation it provides. I'll probably replace it in the Fall or Winter, when it can serve its purpose which, I think, is to aid in warming the engine on cold starts.

Any thoughts on this?

Thought: There's one way to find out.

Thought: BMW Engineering resolved heat issues in the design phase

Thought: Gonna be noisier

 

Thought: Who cares?

Thought: Isn't there something better to waste your time?

Just a thought (or two):yikes:

 

My thinking is that the plastic cover holds and protects the acoustic foam thing. Without the plastic cover, the foam material can be "dislodged" and fails to isolate engine noise.

 

Yeah, the foam is part of the plastic cover; they're attached. And they're both sitting in my garage now.

 

These cars are sold globally in some extreme climates both hot & cold. Personally don't believe pulling the cover will do anything toward improving overall performance.

A motor is a heat engine & the cooling system is designed to keep the heat from getting excessive & out of spec. The cover is not an after thought (hey lets make the engine look cool) no pun intended but part of the whole design.

 

My guess the plastic cover by itself is not too critical, but the plastic cover holding the foam material as a unit serves as noise and heat insulation(plus protecting the components), and plays a part in the overall system design.

 

Last 3 turbos 250 was normal winter & summer.

 

It sounds counterintuitive, but keep under-hood aerodynamics in mind. Engine covers trap heat at a standstill, but are often designed to route air to desired parts of the engine bay when moving. Similar to brake ducts - you can remove them, but doing so may prevent cooling air from reaching where its needed most.

 

Yeah... but no. The cover doesn't have any cooling ducts from a fan or from the grill intake.

 

The OP has convinced himself that he knows something that others don't.

He's on to something and only his perceived anecdotal experience matters.

Those Germans who designed the engine knowing that they would have to shroud it in plastic, and it would have to face stop and go traffic in high temperatures?

They don't live in SoCal and don't get it.

The rest of us who might live in the southwest and see high temperatures?

No, not like LA babe. You don't know. Even though it would appear his car didn't actually overheat, he believes this solves a problem that may not have actually occurred.

Why try to reason with this?

A better topic might be:

"Is AWD with all season tires better than RWD with summer tires in the snow, if I live somewhere where it never snows?"

'If I use ECO Pro enough can I recoup the extra money I spent to buy a car that would have otherwise been fun to drive?"

"I wasn't having this problem, and here's how I fixed it and why you're wrong."

"Anyone else find extra, unnecessary parts under the hood?"

Sometimes in life it's better to JNA, just nod along.

jummo

 

The OP has convinced himself that he knows something that others don't.

He's on to something and only his perceived anecdotal experience matters.

Those Germans who designed the engine knowing that they would have to shroud it in plastic, and it would have to face stop and go traffic in high temperatures?

They don't live in SoCal and don't get it.

The rest of us who might live in the southwest and see high temperatures?

No, not like LA babe. You don't know. Even though it would appear his car didn't actually overheat, he believes this solves a problem that may not have actually occurred.

Why try to reason with this?

I started this thread and asked for people's thoughts. You don't have any, so you turned to insulting me. Do you feel better now that you've insulted a perfect stranger for the crime of asking a question?

Meanwhile, I've researched more. In the automotive engineering industry, these covers are called "engine beauty covers," and their purpose is indeed engine beauty, and they also provide sound insulation to reduce cabin noise.

In some designs, these covers house critical components, such as air intake or attachment points for hoses and electrical components. You can't operate such car without them. And in some applications, these covers are sealed, meaning they contain liquids such as coolant. But this isn't the case with the N55 engine cover; it just has a rubber-like insert which provides sound insulation.

http://www.dupont.com/industries/au...ndustries/automotive/powertrain-engine-system/articles/gm-zytel-innovation.html

Engine covers and housings provide the function as an effective seal containing critical gases and fluids, and they perform many additional functions such as vibration isolation, pressure regulation of blow-by-gases, the extraction and return of oil-mist from blow-by-gases and a attaching locations [sic] to secure other components.

I could not find any auto industry-related indication that these covers are part of the engine's thermal control system. I did find several examples of recalls of these shields, particularly a Fiat in which the shield would come loose, hit the exhaust manifold, and catch fire.

 

An engineer from a car company told me that the engine cover has a purpose. It's there to route air where it needs to.

As for your coolant temps, you can check this in the cluster menu (unlocking with the total of your last 7 vin digits). i used to do this in my old m135i as i was curious to see oil and water temps.

 

I imagine that the foam and the rubber lining serve at least two purposes:

1) Sound deadening; and
2) Thermal insulation that keeps the hood temperature lower

My thought about #2 is that this protects the hood's paint and clearcoat directly above the engine cover. Ever seen older cars with those spots on the hood where the clear coat has flaked off and the paint has faded? I doubt that the engine cover completely prevents that, but it probably helps significantly to reduce it or delay it from happening.

 

This reminds me of a forum post that showed a picture of F30 hood covered in snow, with a specific distinct pattern not covered(due to heat from engine bay). It was a cool picture, and left an impression that it was explicitly designed/done that way.

http://f30.bimmerpost.com/forums/showthread.php?t=1196118

 

there is no good reason to leave it off on purpose.

 

Totally agree.

 

Hood heat is an issue. One of the pop up warning messages on the dash warns of high hood tempratures.

 

I think that is different. I've only seen that warning when the car was at operating temps and I opened the hood. Then it warned me of hot temperatures and to be careful what I touched. I don't think the warning is an overheating warning.

Sent from my Galaxy S8+

 

If the engine cover keeps too much heat in, why don't we simply remove the hood too?

 

Or with that reasoning, why not remove the engine all together. Then heat or sound will not be an issue at all:rofl:

 

Yeabut, it has a roundel.. I think it's there to heat some part up more quickly

 

Here's our X5 35i with N55 engine running fine with plastic engine cover on and a/c running med-high.

Here's my 335i also with plastic engine cover running fine with a/c blasting. Oil temp is always around 205F for me around town, but on long highway drives it goes to 240-250. Probably switching between performance vs efficiency maps.

In Phoenix we consider 105F in summer to be a pretty nice day. If anybody's a/c is shutting off due to overheating in anything short of 120F weather, I'd be making a trip to the dealer.

 

Here's our X5 35i with N55 engine running fine with plastic engine cover on and a/c running med-high.

In Phoenix we consider 105F in summer to be a pretty nice day. If anybody's a/c is shutting off due to overheating in anything short of 120F weather, I'd be making a trip to the dealer.

I took my car to the dealer for an unrelated issue and they applied a service bulletin fix which replaced the 400 watt engine cooling fan with a 600 watt fan. So there is (was) a cooling issue.

I showed the master tech my engine bay and told him I'd removed the engine cover for the summer. He didn't think it was a bad idea at all. More cooling is better.

 

Update: We had another hot day this weekend and I went for a very long drive in the middle of the afternoon. The plastic engine cover remains in my garage. After this drive, I parked and immediately touched the hood of the car, which was cool to the touch. Mind you, my car is white, and I'd expect a hot surface if the car were dark. But the hood is cool after a very hot run. There is insulation affixed to the underside of the hood which dissipates heat away from the hood very well. Even though the plastic engine cover (which I removed) will get very hot, the temperature of the paint on the hood isn't affected.

So I see no reason not to remove the plastic engine beauty cover to improve cooling on the E55 engine. I'll put it back on in the winter, to improve cold starts by insulating the engine.

 

We've given you lots of reasons to keep the cover on. You decided that the engineers don't know what they're doing, though.

 

I respect and appreciate all the time. But none of the reasons provided were fact-based:
1) The BMW Engineers are smart and put the part there for a reason: True, but the reasons were appearance and sound deadening. These reasons are known. But there's no evidence that it improves airflow and engine cooling. My data show that the beauty cover gets extremely hot, while the hood remains cool even when the beauty cover is removed. I may even test whether exterior hood temperature increases when the beauty cover is present.

2) The cover presents good paint from wearing out: In my tests, it appears that the insulation affixed to the underside of the hood accomplishes this feat, not the engine beauty cover. There is no evidence of this, and the heat containment of the beauty cover could exacerbate paint wear, not prevent it.

3) Cold engine warm up: It is possible that the substantial insulation of the beauty cover reduces engine wear during cold start by improving engine warm up from a cold start. For this reason, I will reinstall the cover before winter.

The technician at my dealership didn't have any concern that I removed the cover. I just really doubt this is going to cause a problem. More importantly, there's no fact that any damage can occur.

Last point: For all the talk of "Engineers test airflow so perfectly, etc," my dealership replaced my engine cooling fan with a 50% higher wattage unit. So there was a cooling problem with these engines and all of the engineering simulation didn't catch it.