What I do is remove the air cleaner box and computer, then I zip tie a plastic bag over the computer's electrical harness connector and the throttle body inlet. After everything is washed and rinsed, I dry the engine with the blower port of the garage vacuum.
Engine Bay Cleaning
- Thread starter NewEnglander
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Here's a guy going to town at the self-serve car wash with no prep:
https://www.youtube.com/watch?v=3JXxCGUZVYw
https://www.youtube.com/watch?v=3JXxCGUZVYw
I go to the car wash and spray soap on the entire engine compartment, then rinse. My practice is to not get the nozzle closer than 3 feet from any part or component. The bay is really getting soaked with soap and water, not directly hit with high pressure. I've done this with every car I have owned over the last 25 years and have never had a single problem. My engine bays look brand new for the lifetime of the vehicle.
I've cleaned a lot of engine bays and here are my observations:
1. Only use a hose with a nozzle that sprays. You don't want power washing here, you also don't want such large amounts of water to pour out like out of an unrestricted opening of a garden hose or pouring water from a jug or anything like that. Both are too much.
2. Before starting, find all of the places that could be potential problem places and check them or seal them. Here are some examples:
* Under hood fuse boxes: Check that the rubber seal on the lids are still working.
* All fluid reservoirs: Check that the caps on the fluid reservoirs are all sealed.
* Dipsticks: There have been cases in the past where dipsticks were not water tight. You'd be surprised at how bad of a seal some dipsticks have. I don't take chances here with a hose when I can just go over it manually with a wet towel and not worry about it. Honda has had some really loose dipsticks and Chrysler had a recall on some of their automatic transmissions because a bad dipstick seal allowed water contamination. Find the location of the dipsticks and avoid these areas entirely (tape a shopping bag around the top or something).
* Intake piping: If you have a vacuum leak your engine would probably run like garbage but there have been cases where people had tears in their intake snorkel past the MAF and didn't even know it. Along the same vein make sure the lid on your air cleaner box is properly secured.
3. I wouldn't use a degreaser, only water but that's just me. The only time I would use a degreaser is if there was serious oil to clean up and then I'd be very careful about where to spray it. I've used degreasers in the past and have had problems arise. One example was where a little degreaser mixed with some water ended up past a plug wire boot seal and the spark plugs ended up completely corroded (as in ashy white).
4. If you hose a hose spray like I mentioned above, electrical connectors and even the alternator are safe to skim by with the spray, as long as you don't focus on them for any length of time.
5. I usually use the hose only to wet down the engine and hose off any loose dust, dirt, salt or debris, then I use a wet microfiber towel (along with water in a bucket) to manually wipe down all of the areas and physically clean the dirt off. The areas you didn't hose off like dipsticks are handled manually with the towel.
6. Keep moving the hose around, don't flood any areas. Be mindful of water possibly building up and ended up going past reservoir cap seals for example. Also be mindful that some things like dipsticks could be in recessed places where water could build up and force their way past the seal. For example some Honda AT's have dipsticks that are on the transmission case itself, not a tube attached to the case. On some of these it is possible to have water build up around the recessed dipstick if you're not careful.
7. Wring out the microfiber towel so that it's damp but not soaked and use it to soak up and dry all of the areas that you went over wet.
8. If you have an air compressor (pneumatic or electric), use it to blow the air out of the engine bay to speed up drying. This is optional.
1. Only use a hose with a nozzle that sprays. You don't want power washing here, you also don't want such large amounts of water to pour out like out of an unrestricted opening of a garden hose or pouring water from a jug or anything like that. Both are too much.
2. Before starting, find all of the places that could be potential problem places and check them or seal them. Here are some examples:
* Under hood fuse boxes: Check that the rubber seal on the lids are still working.
* All fluid reservoirs: Check that the caps on the fluid reservoirs are all sealed.
* Dipsticks: There have been cases in the past where dipsticks were not water tight. You'd be surprised at how bad of a seal some dipsticks have. I don't take chances here with a hose when I can just go over it manually with a wet towel and not worry about it. Honda has had some really loose dipsticks and Chrysler had a recall on some of their automatic transmissions because a bad dipstick seal allowed water contamination. Find the location of the dipsticks and avoid these areas entirely (tape a shopping bag around the top or something).
* Intake piping: If you have a vacuum leak your engine would probably run like garbage but there have been cases where people had tears in their intake snorkel past the MAF and didn't even know it. Along the same vein make sure the lid on your air cleaner box is properly secured.
3. I wouldn't use a degreaser, only water but that's just me. The only time I would use a degreaser is if there was serious oil to clean up and then I'd be very careful about where to spray it. I've used degreasers in the past and have had problems arise. One example was where a little degreaser mixed with some water ended up past a plug wire boot seal and the spark plugs ended up completely corroded (as in ashy white).
4. If you hose a hose spray like I mentioned above, electrical connectors and even the alternator are safe to skim by with the spray, as long as you don't focus on them for any length of time.
5. I usually use the hose only to wet down the engine and hose off any loose dust, dirt, salt or debris, then I use a wet microfiber towel (along with water in a bucket) to manually wipe down all of the areas and physically clean the dirt off. The areas you didn't hose off like dipsticks are handled manually with the towel.
6. Keep moving the hose around, don't flood any areas. Be mindful of water possibly building up and ended up going past reservoir cap seals for example. Also be mindful that some things like dipsticks could be in recessed places where water could build up and force their way past the seal. For example some Honda AT's have dipsticks that are on the transmission case itself, not a tube attached to the case. On some of these it is possible to have water build up around the recessed dipstick if you're not careful.
7. Wring out the microfiber towel so that it's damp but not soaked and use it to soak up and dry all of the areas that you went over wet.
8. If you have an air compressor (pneumatic or electric), use it to blow the air out of the engine bay to speed up drying. This is optional.
Originally Posted By: NewEnglander
Anyone ever use the Gunk Foam Engine Cleaner? I heard about this process (foam) a while back and seems straight forward. Cover your engine in it and lightly rinse with water.
I have. You better hope you rinse all of it. If even a little ends up somewhere mixed with water, it will corrode metals. In my case, some of it ended up past spark plug seals somehow (I didn't even shoot the area directly) and corroded the insulator and fastener part of the spark plugs.
Anyone ever use the Gunk Foam Engine Cleaner? I heard about this process (foam) a while back and seems straight forward. Cover your engine in it and lightly rinse with water.
I have. You better hope you rinse all of it. If even a little ends up somewhere mixed with water, it will corrode metals. In my case, some of it ended up past spark plug seals somehow (I didn't even shoot the area directly) and corroded the insulator and fastener part of the spark plugs.
Originally Posted By: WobblyElvis
I was told by an auto detailer that cleaning an engine was something you should never do. He did it for a living but thought it lead to corrosion and other problems. It sure would be nice to have a clean engine but I just live with the dirt. I live in the rust belt, maybe it's a different story in other environments.
that's nonsense. that would be a "detailer" you need to stay away from
I was told by an auto detailer that cleaning an engine was something you should never do. He did it for a living but thought it lead to corrosion and other problems. It sure would be nice to have a clean engine but I just live with the dirt. I live in the rust belt, maybe it's a different story in other environments.
that's nonsense. that would be a "detailer" you need to stay away from
Originally Posted By: funkymonkey1111
Originally Posted By: WobblyElvis
I was told by an auto detailer that cleaning an engine was something you should never do. He did it for a living but thought it lead to corrosion and other problems. It sure would be nice to have a clean engine but I just live with the dirt. I live in the rust belt, maybe it's a different story in other environments.
that's nonsense. that would be a "detailer" you need to stay away from
Agreed. Everything in the engine bay is designed with the expectation that it will be both directly and indirectly exposed to water. Unless I had a pre-2000 car (and maybe not even then) I'd have no hesitation whatsoever to use my normal engine cleaning method:
1. Spray degreaser/soap on a cool engine bay
2. Light mist with hose to activate and spread the soap
3. Let sit for a few minutes
4. Agitate with brush or mitt where/if needed
5. Rinse with a heavy spray from the hose
6. Close hood, turn engine on, let heat evaporate the remaining water
7. Inspect and repeat any steps if necessary (it's usually golden the first time)
Originally Posted By: WobblyElvis
I was told by an auto detailer that cleaning an engine was something you should never do. He did it for a living but thought it lead to corrosion and other problems. It sure would be nice to have a clean engine but I just live with the dirt. I live in the rust belt, maybe it's a different story in other environments.
that's nonsense. that would be a "detailer" you need to stay away from
Agreed. Everything in the engine bay is designed with the expectation that it will be both directly and indirectly exposed to water. Unless I had a pre-2000 car (and maybe not even then) I'd have no hesitation whatsoever to use my normal engine cleaning method:
1. Spray degreaser/soap on a cool engine bay
2. Light mist with hose to activate and spread the soap
3. Let sit for a few minutes
4. Agitate with brush or mitt where/if needed
5. Rinse with a heavy spray from the hose
6. Close hood, turn engine on, let heat evaporate the remaining water
7. Inspect and repeat any steps if necessary (it's usually golden the first time)
i would not bother, you can cause damage and really gain nothing. keep areas such as oil fill/cap, radiator fill, windshield wiper fill, etc clean but besides that I would just leave it.
What I used to do was cover the alternator and the computer with aluminum foil. It molds to the parts shape. Then, spray EVERYTHING with full strength SIMPLE GREEN. I would use a parts washer brush to clean the very heavy soiled areas. After about 20 minutes soaking, rinse. Run the engine, go for a ride, etc. Let the engine cool down and use Silicone spray EVERYWHERE! Wipe down the hoses and any excess Silicone spray and your engine bay will be very protected and look brand new.
I'd caution against using Simple Green on a modern engine, esp. full strength. It has been known to be hard on chemical conversion coatings and certain metal plating (like zinc) which can leave bare aluminum or steel exposed to corrosion or rust. BlueOvalFitter may be saved by his dousing with silicone spray but I'd encourage others NOT to use this product for this purpose. IF you do, rinse, rinse, rinse again, and treat the bay with some sort of dressing.
Originally Posted By: gofast182
I'd caution against using Simple Green on a modern engine, esp. full strength. It has been known to be hard on chemical conversion coatings and certain metal plating (like zinc) which can leave bare aluminum or steel exposed to corrosion or rust. BlueOvalFitter may be saved by his dousing with silicone spray but I'd encourage others NOT to use this product for this purpose. IF you do, rinse, rinse, rinse again, and treat the bay with some sort of dressing.
Simple Green Extreme is aluminum safe. Works pretty well too.
I'd caution against using Simple Green on a modern engine, esp. full strength. It has been known to be hard on chemical conversion coatings and certain metal plating (like zinc) which can leave bare aluminum or steel exposed to corrosion or rust. BlueOvalFitter may be saved by his dousing with silicone spray but I'd encourage others NOT to use this product for this purpose. IF you do, rinse, rinse, rinse again, and treat the bay with some sort of dressing.
Simple Green Extreme is aluminum safe. Works pretty well too.
Originally Posted By: rooflessVW
Originally Posted By: gofast182
I'd caution against using Simple Green on a modern engine, esp. full strength. It has been known to be hard on chemical conversion coatings and certain metal plating (like zinc) which can leave bare aluminum or steel exposed to corrosion or rust. BlueOvalFitter may be saved by his dousing with silicone spray but I'd encourage others NOT to use this product for this purpose. IF you do, rinse, rinse, rinse again, and treat the bay with some sort of dressing.
Simple Green Extreme is aluminum safe. Works pretty well too.
There ya go. Haven't seen that around but that looks like what you'd want to use.
Originally Posted By: gofast182
I'd caution against using Simple Green on a modern engine, esp. full strength. It has been known to be hard on chemical conversion coatings and certain metal plating (like zinc) which can leave bare aluminum or steel exposed to corrosion or rust. BlueOvalFitter may be saved by his dousing with silicone spray but I'd encourage others NOT to use this product for this purpose. IF you do, rinse, rinse, rinse again, and treat the bay with some sort of dressing.
Simple Green Extreme is aluminum safe. Works pretty well too.
There ya go. Haven't seen that around but that looks like what you'd want to use.
I use purple power degreaser, it’s cheap and powerful. But yes, thoroughly rinse and rinse again
I personally do the following:
1) Wrap open intake and alternator with plastic bag, remove engine cover.
2) Liberally spray Meguiar's Super degreaser (diluted 4:1 as per instructions on the bottle) on a cool engine , letting it soak for about 5 minutes
3) Agitate the spots where more dust/grease may accumulate - a small wheel brush is all I use
4) Wash with free-flowing water (I do not blast water everywhere).
5) Use leaf blower or shop vac in reverse to blow water out, dry as best I can
6) Spray with Meguiar's Hyper Dressing (diluted 4:1 for a more matte finish). This is water based so it won't get greasy
That's it. It usually takes less than 20 minutes with me taking my time.
1) Wrap open intake and alternator with plastic bag, remove engine cover.
2) Liberally spray Meguiar's Super degreaser (diluted 4:1 as per instructions on the bottle) on a cool engine , letting it soak for about 5 minutes
3) Agitate the spots where more dust/grease may accumulate - a small wheel brush is all I use
4) Wash with free-flowing water (I do not blast water everywhere).
5) Use leaf blower or shop vac in reverse to blow water out, dry as best I can
6) Spray with Meguiar's Hyper Dressing (diluted 4:1 for a more matte finish). This is water based so it won't get greasy
That's it. It usually takes less than 20 minutes with me taking my time.
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