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Engine Cleaning

Discussion in 'DIY (Do-It-Yourself)' started by kearnsclan, Mar 21, 2010.

    kearnsclan guest

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    Just cleaned my engine to try to find where I had an oil leak.
    Suspect VC gaskets.
    Think now is was loose PS reservoir hose connection and vanos solenoid gasket.
    Should be a simple fix..

    Used Simple Green to clean the engine......WOW!! Did a great job !!

    Hosed off the motor while running.

    Got this tip from a BMW tech !!
    • Member


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    do you have to do any hard scrubbing with the Simple Green? my engine looks terrible and I'd really like to clean it up

    kearnsclan guest

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    I didn't scrub at all. Pretty amazing stuff really. I have a VC leak and the engine and lower support frame was really grimy. Sprayed it on full strength, let soak for 10 min or se, then blasted it off with a garden hose attached to pistol-squeeze grip type nozzle.
    Even got crazy and jacked-up the front end and sprayed from underneath and blasted it clean with the hose.
    Now I can keep an eye on my oil leak and find any new ones, Hope this helps.....
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    John in VA

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    While you guys have engines with a lot of plastic bits, I'd be careful using Simple Green full strength. Make up several dilutions in different spray bottles - 1:1, 1:5, 1:10 SG to water - and try them out. I've seen strong SG solutions screw up the finish on aluminum.

    kearnsclan guest

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    Word to thw wise...

    Sounds like good advice. I'll try it out.

    callmasterIV guest

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    for the stronger stuff

    I just went through a head rebuild, and am sure the dirt in the compartment is 300k miles old:)
    As I diddnt wanna scrub with wirebrushes, ive used only
    2 Microfiber towels and the stuff i've been using Hoppes'9 Gunsolvent.

    Spray, let it soak, spray wipe...

    Cleans very well .
    Smelly! (for 50-90 miles) but ok.

    Causes carbonation!!! so for exterior use onyl.
    And there , after you got the grease off, id say use somethign else again to clear he solvent leftovers away.

    9$ usually for the bigger bottle, bottle lasts for a engine compartment.
    Works on hoses/rubber and plastic as well. Carbon fiber, i have no idea.

    faiyaza guest

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    While on? Really?

    I was nosing around my e90 engine compartment and saw all kinds of cabling and harnesses. Is there any kind of technique involved when hosing the engine down to avoid any electronics shenanigans?

    For the life of me, I never would have thought of doing it while on. I'm really surprised it works, but if the tech says its kosher...

    I'll need to drum up the nerve to try this one day. /me looks for the bottle of Jack in the cupboard
    • Member


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    When evaluating claims like this it helps to remember the phrase, "50% of all doctors graduated in the bottom half of their med school class."
    • Member

    Brian A

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    It's easy to do: just do it. It seems BMW engines are pretty tolerant to water spray. Give it a good spray with plain water first to see what needs solvent.

    Auto parts stores also sell biodegradeable engine cleaner. Probably best to do this all at a commercial car wash where oil is (hopefully) skimmed before waste water is returned to the sewer system.

    Yeah, rubber doesn't like degreaser very much, but I doubt it harms mechanical integrity. Likewise aluminium, although I let degreaser sit on my manifold for a while because I actually liked the patina it was creating.

    Engine cleaning is something you do every couple of years: not weekly like washing your car (well, okay, I only wash my car a couple of times a year).

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