What can you safely power wash under the hood?

Status
Not open for further replies.
No need to, use Gunk engine cleaner, cover air box, fuse box, and battery, spray the cleaner over everything else and just hose off, works great
 
Originally Posted By: Miller88
Originally Posted By: mjoekingz28
I used a garden hose once......next week there goes the tensioner.


As said, if you are relentless and are going to do it anyway.....maybe you should get on the highway for 30 minutes after performing the task to help minimize risks.




Really though, citrus clean, tire shine and some shop towels would be 'best'.


I've never had good luck with auto tensioners. Probably was it's time to go.



It probably was. The point was that the water helped finish it off and made it shewn to me it is not a good idea. Its like taking a pressure washer to a work truck's floor liner. There is alot of collateral damage from water splashing up under the dash and into areas where you dont intend it to go.....and thats for the few who knowwhere to specifically spray anyway. Automobiles arent four wheelers or dirtbikes.

And besides, most stains and grime need agitation. Like you would get with a towel, brush or sponge...not a stream of water.
 
Originally Posted By: Reddy45
Here is what you do if you want to do the job right.

1. Dry vacuum the engine bay. Just pick up the big debris like leaves and such.

2. Lightly mist with water

3. Spray a diluted all purpose cleaner and allow a few minutes to dwell.

4. Agitate with a soft brush

5. Rinse with natural water pressure from hose. No need for spray nozzle.

6. Use shop vac or leaf blower to blow dry engine.

7. Use some light quick detailer with a microfiber towel on the nice parts to give a nice sheen.









+1


Just a gentle drinkable stream not putting 2000psi all gung ho on it. I like your style. If I were to use waterflow I think this is how it would be.
 
Originally Posted By: Kestas
Seals - as in shaft seals and bearing seals - are part of the products our company engineers. We cringe at the thought of somebody power washing right at the seal... especially a greased application. The water injected would destroy the bearing in short order by compromising the lubricant. Maybe that's why the tensioner failed shortly after power washing. Plus, these seals are an easy target; that's where lubricant purges and makes the biggest mess.



This was with a garden hose not pressured water just to be clear
 
Originally Posted By: BrocLuno
I've gone close to 300,000 miles on some vehicles that were never cleaned except the parks that needed repair. The motor does not care... I do blow off excess dust once in while with air or a leaf blower...

Is this a clean thing, or a show-off thing?



The motor does care. Dirt prevents heat from dissipating. Dont forget to brush and hose off your radiator and condensor with low pressure water. They care too.
 
Originally Posted By: Win
I wash and use the brush under the hood of every car about every other time I go to a car wash.

Everything I've ever owned, made since the late '80's or early '90's, is well sealed and water is a non issue.

An engine that won't run soaking wet has another name: junk.



Even in the strongest rains, my engine bay doesn't get wet. I have no need to prove anything by power washing it. If designers didn't care about wet engine bays, they wouldn't give us hoods. An engine that is frequently run soaking wet will eventually....become junk. I hand cleaned/degreased my 2002 when I first got it. Maybe once more since then. The engine bay is sealed pretty good. Other that oil leaks, it stays pretty clean from year to year. I've never cleaned an engine and saw a decrease in operating temps. Last time I cleaned an engine was in 1999.
 
I am always amazed by that part of human psyche that would demand the normally unseen engine compartment that provides a vital service be spotless clean. Using a pressure washer just takes up up another level from there. There are so many things you can damage and what is the payoff? You'd be better off putting the tinfoil and saran wrap on your head and go down to the local spa and get your backside bleached. Sheesh! I'll sleep perfectly fine at night knowing that only specified engine fluids are under my hood.
 
Last edited:
Breath, everyone, breeeeeath.

I am not trying to "prove" anything or "show off an engine" or whatever. I just bought a new to me car and although the interior and exterior is in excellent shape and well detailed, the engine bay is probably has not been cleaned from day one. I do want to clean it, just once. It does look odd to see a dirty engine bay in a spotless car. The vast majority of the pressure washing would be on the large plastic engine cover, and around the front hood latch area. I am unfamiliar with this, but I thought it would probably be safe to do so.
 
I use a pressure washer, but like I said. Wide fan nozzle and further distance. It helps blow the rinse water off and down. I never have any bad results. I enjoy opening the hood to a clean engine. You don't need to clean the engine bay, but some of us like to do so.
 
Simple Green would be the last thing I would use. Not only does it have a tendency to leave a white crust on parts, but it is also absolute terror on coated aluminum.

It is unlikely that cleaning will destroy a truly good part. But if you have any parts that are not so perfect, washing can destroy them where they may have gone for half of forever without liquid intervention. Just something to understand when you begin.

Engine bay cleaning is a service I no longer offer, just for that reason. If some part clinging to life goes out, nobody wants to hear that "it would have eventually died anyway".
 
Originally Posted By: aquariuscsm
I think thorough drying is important too. I use a leaf blower to completely dry everything when I'm through cleaning. I clean mine on a regular basis.

X2, use a leaf blower also
cheers3.gif
 
I've powerwashed my engine bay multiple times, i start the engine and drive around to get the engine hot, then i bring it to a guy that i know that has a power washer, i cover the distributor, coil and battery with plastic bags and wash it with the engine hot and running, never had any problems i just do it in the summer and after i do it i take a long drive at high speed on the highway for half an hour or so to dry everything up.
 
Originally Posted By: FordCapriDriver
I've powerwashed my engine bay multiple times, i start the engine and drive around to get the engine hot, then i bring it to a guy that i know that has a power washer, i cover the distributor, coil and battery with plastic bags and wash it with the engine hot and running, never had any problems i just do it in the summer and after i do it i take a long drive at high speed on the highway for half an hour or so to dry everything up.


You have the advantage of a decades old, "low tech" engine bay with plenty of room to prevent spraying it everywhere and little in the way of electronics to ruin. I would also cover the alternator, voltage regulator, and anything else in the charging system. Still, when I cleaned my 1960's and 1970's engine bays years ago, it only took 1-2 hours or so by hand every few years. A big advantage of doing it by hand is that you see and touch every component in the engine bay. If there are problems of any sort you'll be much more likely to spot them.
 
Reading here prompted me to wash out the engine bay on my two vehicles. A friend had come over that had his vehicle detailed including the engine. Wow I was impressed with the looks of it. I like to keep my engine generally clean and this detailing was the next level I wanted to learn how to do. So a few Youtube videos and reading here I got some courage and did my 150.

I bought a spray bottle of Purple Power and a can of Trim Spray. I wrapped tender electrical stuff in foil. I got out my power washer and went to work. After it was done I was really happy with the results. It was surprising how easy it was to do the job.

A few days later the Nissan got the same treatment. I didn't use the power washer on it. Just a hose with water nozzle. I got the same clean results. My neighbor came over and looked at my work and was sure I had bought new plastic parts they looked so good. I got out the Trim Spray and demonstrated what it does to faded black plastic.

The job is worth learning how to do and then getting in and doing it. Good luck to anyone else thinking about it. It is worth it. I do a lot of DIY so I like having a clean work area. This does take it to a higher level.
 
What can you powerwash under the hood?

NOTHING!

If you want to clean it, I use an old toothbrush, water, and dish-washing detergent on some parts and for the really greasy parts this stuff:
comet-cleaner.jpg
 
I can see the danger of an actual power washer, but for off road vehicles, even soft roaders, those get wet with water splashed up from mud puddles quite frequently. How is low pressure from a hose any worse? Or are you saying that any water, even splashed water will be bad?
Does that mean that say, Jeeps with the vented hoods will eventually die from the rain that will get in those vents?
 
Like I said I've been doing it for many years with no ill effects. I think using a little common sense and not blasting high pressure directly into electrical connectors and stuff goes a long way to avoiding trouble. A wider fan nozzle on the pressure washer lets you make quick work of cleaning without damaging anything.
 
Status
Not open for further replies.
Back
Top