I have used a variety of items.
Oven cleaner is the mack daddy of them all. I've never cleaned my m54 with it though.....but it gets rid of everything. For the dirtiest of engines. Removes caked oil......acidic. I would use this on my m54....but its never been dirty enough to warrant the big dog
Auto parts store.......foamy engine bright......does well use it for years. Not for the dirtiest but definitely for the dirty. Removes caked oil.....let it soak in
And then there's the way I do it normally. When I was in the car wash business I learned a lot about the soaps. Basically the way it cleans your car.(and some of you might not like the idea of this)
It uses acid.....to eat a micron layer of clear coat off of your car. So small you could wash for 20 years and it wouldn't eat the clear off. When the clear gets eaten the dirt goes with it. You are removing the base that the dirt is held on. My dad ruined several paint jobs getting the acid part of his soap manufacturing line to work right. The stuff you buy or use has had the bugs worked out for years now. This was back in the 70s.
So now we get into the pre soak, tire cleaner, super wheel cleaner at the self serve car wash.
These soaps need to be washed off right away.......don't pre soak it and then drive somewhere with any of these on the car still. Make sure you have enough money to wash them off.
Because they have more acid than the regular soap....they are stronger soaps for this reason.....if left on they will eat into lexan windows......not a big deal just wash it off right after you apply it.
Now that you know the nature.......I use super wheel cleaner or pre soak on my engine. It is perfect for cleaning them. My engine bay is spotless. It works very well and you will love the results.
On another note.......stay away from the exhaust manifold. I haven't cracked my BMW manifold. But I did crack another car I had. The cold water cools it down too fast and the metal separates. Don't be afraid of it.....just don't douse it with water......if you wait for the car to cool down......and you can touch the manifold.....you are fine. Just be cautious. Ideally ......warm engine is better.....and I don't mean you just drove the car and shut it off warm......I mean let it cool for half an hour warm. When you can touch the exhaust manifold and not have a third degree burn then the manifold is for sure safe to wash . ......I am not liable if you burn yourself touching manifold....just don't be stupid
Then there is something 90% of the human population doesn't know. And I have tried this on many older cars.....but have not tried it on the BMW yet. I don't know the effects.....it works on glass but I have not tested it on the carlex style windows because the idea is new and I have not completely tested it yet. It was tested on my 79 trans am and my 86 omni GLH. I was amazed at the result....then we tried it on a Ken worth semi truck....and it worked there too.
So what is it........CLEANING YOUR WINDSHIELD WITH STEEL WOOL.
You would think it scratches it....but it doesn't. It makes it look new. It might even take the sandblasted effect out of an older windshield. I don't know.....when I heard it I didn't believe it. So I tried it and now experimenting.
If your not comfortable trying it......DONT. there are you tube videos on it and from what I can see.....it works. Will I try it on my e46 glass.? The windshield..... yes.....the side windows...with caution. It was taught to me by an old glass guy.
My friend had a car in his shop....his son wrote his name in the dust on the back window. My friend left it there.
When he washed the window his sons name was etched in the glass. No amount of polishing with mothers polish or washing took it out........I used...... with no water on his dusty window. Steel wool.....the window looked new.....the car was a 1986 honda. The reason I didn't use water was because I wanted to see if the steel wool would used the dust to make scratches......it cut through the dust dry and still polished the window. If someon wants pictures I'll post them.
Last edited by glhx; 02-15-2013 at 02:00 AM.