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cleaning engine bay

Discussion in 'Maintenance & Upkeep' started by reggiecab2000, Aug 5, 2012.

  1. reggiecab2000

    reggiecab2000 Member

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    hey guys,
    im just curious as to the best, most effective, techniques/methods there are for completely washing/cleaning out underneath your hood???
    any advice is appreciated, just looking to thoroughly remove as much dirt/grime/crap as possible.
    thanks!
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  2. aloxdaddy99

    aloxdaddy99 New Member

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    I spray the engine bay with Simple Green let it sit for a few minutes than hose it down. You may need to do it a few times for the first time. But know when I wash the truck I also clean the engine bay. This helps with a few things. If I see a build up of a fluid or something I know there is a leak and it also keeps the engine bay looking clean.
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  3. PantheraUncia

    PantheraUncia New Member

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    I do something similar with simple green, then I scrub a little with a soft brush and then I wash it off with a pressure washer.

    Typically I will spray down the engine with the simple green or light degreaser, scrub it, and have the power washer ready, next I jump in and start the engine and then jump back out and hit it with the pressure washer.

    the reason for that is,

    if the engine is not running, you can potentially get it wet enough that it will not start back up if water gets somewhere it should not. The down side is, you have to get the simple green off before the engine gets too hot cause you do not want to crack the engine. ( that is why you start with it off, and then turn it on before hitting it with the water, the engine is cold so the water will not cause the engine block to crack, but the engine heats up quick, so it is a timing thing.

    Disclaimer: I am not an expert and if you drowned your engine by cleaning it and it will not start, or cause any damage of any kind to your engine; I am not liable for what you did.
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  4. Cheez

    Cheez Member

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    I'm going to go with simple green as well. I've just sprayed it under the hood before washing the truck. When I finish washing I just hose it off. I've done this for quite awhile so you may need a pressure washer depending on the grime thickness.
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  5. reggiecab2000

    reggiecab2000 Member

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    well so far simple green seems like a unanimous winner
    are there any electrical spots to really try to keep the water away from? or is it all fair game for the most part
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  6. PantheraUncia

    PantheraUncia New Member

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    My truck is the same year as yours, but I have the 5.3L engine.

    The last time I did it, I wanted to get as much grime off as possible. We don't have distributor caps on our engines, so almost anything is fair game.

    I tend to be careful around the fuel rails and coil packs to the left and right of the intake manifold and then the spark plugs. I did get too much water around my knock sensors and they were lighting up my dash with error codes for 2 months until they completely dried out (under the intake manifold) so be careful there.

    Also watch the spark plug wires and make sure they are tight around your plugs so water does not get in there.

    I also put the truck on ramps and degreased and power washed the under side of the engine/transmission also, but you can be less careful from the bottom.... any time it rains water splashes around under the truck.
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  7. ChevyBoy2009

    ChevyBoy2009 New Member

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    I would keep the water away from your alternator also
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  8. Skippy

    Skippy New Member

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    I take the vehicle to the car wash and use the Tire-degreaser (it's green usually when it finally comes out the hose) all over the engine. Occasionally, after some serious mudding, I have to wash first. I ALWAYS use the low pressure wash spot free rinse (usually pure water) to clean the engine compartment before (if muddy) and after the degreaser.

    When I spray the degreaser, I do it over EVERYTHING in the engine compartment. I've done this for years, and never had a problem. (It also helps that I use dielectric grease on 100% of my electrical connections, and those I work on. I go through a couple tubes a year.) It has the added value of making the black plastic stuff look great when you're done.

    Once I let the degreaser sit for a while (a couple of minutes) I wash it down with the low-pressure spot free rinse, until it's all washed away. The sole exception to the low pressure wash is when I'm trying to get the bug grime out of the radiator fins. I'll use the standard rinse, but always hold it well away from the fins (to not bend them under the pressure).

    I've done this with both the engine running and off, no problems either way.

    I do this to LOTS of vehicles I work on, as I find the engine compartment's nastiness is a real inhibitor to working on some parts or doing basic maintenance (like spark plug changes). Much easier to work in a clean environment. For 3 bucks and 5-100 minutes, it sure beats hand spraying things down with simple green! Since my shop prices are "free plus the cost of parts," (select clientele, don't bother asking if you can bring it over, it's pretty much a neighborhood and family thing I do as a hobby!), if a compartment is nasty, I require folks to clean it up before I work on it. I typically will just ride with folks over to the car wash (a couple blocks away) the day before we do the work.

    The only thing you have to watch for is getting the degreaser on paint. It WILL strip wax. Typically, I'll clean and throw a coat of wax over anything that gets splashed, afterwards. Easy to do with modern applications. The same should be done for Simple Green overspray as well.

    -Skippy
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  9. Enkeiavalanche

    Enkeiavalanche Moderator

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    White Lightning or Simple Green both work good There is also P-21 Moyorcycle cleaner that works great. As for High Preasure?? I would NOT use that. A light spray (more then a mist) Is all I would do and keep the water away from the Alt and Air cleaner.
    #9
  10. aloxdaddy99

    aloxdaddy99 New Member

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    When I come off the beach after a day of slinging sand the first car wash I see I stop. I do as Skippy described. I want to get all the sale water and sand off of anything that can be taken care of. I have done this on all my Jeeps as well as my truck. I try to keep my engine bay as clean as I keep my truck. Especially since I have painted the parts that I have. I have never had any kind of issue by doing this. It might not be the best to do but it is how I do it.
    #10
  11. pmf608

    pmf608 New Member

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    I just want to jump in here and caution anyone who uses a pressure washer to clean their engine - at least for those of us with the V8s anyway. I always assumed that as long as I kept the pressure away so that nothing was directly blasted, it wouldn't cause any problems. BUT, I rinsed my engine bay with a pressure washer on Thursday, and on Sunday I got a check engine light for a defective knock sensor. My research since then shows that apparently when you get that much water in there, it can sit below the intake manifold and corrode the knock sensors. A lot of the cases of bad knock sensors (P0332 code - only the rear knock sensor ever seems to get water damage) seem to happen a couple of days after the engine bay is washed. Sometimes it goes away, sometimes it doesn't. If my problem doesn't go away once its had a chance to dry, I'll have to replace both knock sensors and the wiring harness because I don't want to have to remove the intake again if the other one fails. The cost in that case would be about $200-$250 plus about 3 hours worth of labor... that adds up to about $500 or more total if you have a shop do it (at least in my area).

    Anyway, after all that, what I'm trying to say is just be sure to wash your engine bay carefully.
    #11
  12. reggiecab2000

    reggiecab2000 Member

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    well it sounds alot like some guys should do a nice how to, or DO and DONT section on this topic LOL
    might benefit alot of people
    #12
  13. reggiecab2000

    reggiecab2000 Member

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    okay so i just sprayed out my engine bay....
    i used skippys method, seems to have been good so far, started up and didnt die...
    however, ill use simple green and rags once i replace my fuel injectors to get down to the finer cleanliness...



    quick question... i know this aint the right thread but...
    ive had some misfiring problems for a few weeks, only on cold starts, and goes away once the engine is hot, but i noticed that after doing this engine wash and driving home then, to and from an autoparts store, it seems to have amplified the stumbling/misfiring. made it misfire while my engine was actually hot...
    so are fingers pointing more towards ignition caused misfiring now??? since being wet seems to have done this?
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  14. Skippy

    Skippy New Member

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    Two things. Not likely getting your engine wet would cause this. You'd have to actually break electrical connection at a fuel injector or spark plug. If you're concerned you might have done that, pull the electrical connections and smear some dielectric grease on them, and reconnect. If your misfiring is still there, you likely have a different problem (This is actually what I'm leaning toward anyway, since your engine was already misfiring...)

    When was the last time you changed plugs, and did you double check the gapping on them? Over time, the plugs' gaps will widen due to wear, takes a lot of voltage to cross that gap and a few misfires only amplify that due to fouling. I'd check plugs first, then check your fuel injectors. To determine if your injectors are firing, just hold a screwdriver against them (metal end on the injector) and the handle against your hear, you'll hear the tick tick tick from the pulsing if it's firing consistently.

    Beyond that, check your fuel pressure, and replace your fuel filter, if you've got one and haven't already done so.

    -Skippy.
    #14
  15. reggiecab2000

    reggiecab2000 Member

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    yes, i did those some time back, i actually created a thread about it on here recently, i was just too lazy to pop it up real quick, but nothing ignition I know of, but i will be replacing my injectors whenever they get here :)
    #15
  16. zigger215

    zigger215 New Member

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    Good way to test plugs and gaps, start truck, put foot on brake and gas (power brake). Apply small amount of load, if you have a plug issue, wire, plug, gap, you should here small popping and missing instead of a nice consistent groan.
    #16

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