Engine bay needs cleaning
Drifting
Joined: Jun 2013
Posts: 1,294
Likes: 367
From: Iowa
Personally, I would never use a pressure washer on the engine bay. High pressure can get past the electrical seals. Garden hose is what I would use. Big one is covering the alternator. Your best bet is to watch a bunch of different YouTube videos from pros to see what they do/recommend.
Le Mans Master
Joined: Sep 2006
Posts: 9,598
Likes: 960
From: Palm Harbor not far from Sebring Florida
St. Jude Donor '11
Oldtimer
I trust Adam of Adams Polishes and he has a video where he uses a pressure washer. Here is the link Bing Videos
Pro
Joined: Oct 2023
Posts: 668
Likes: 917
From: Iowa
On a side note, this is the best engine bay cleaner I have ever used. It is expensive, but it does the job and leaves no spots if rinsed well with a garden hose sprayer.
At a minimum, cover the alternator with a plastic bag from the grocery store.
At a minimum, cover the alternator with a plastic bag from the grocery store.
Drifting
Joined: Sep 2017
Posts: 1,464
Likes: 771
From: Miami
C7 of Year Finalist (performance mods) 2019
Just be careful. Here in Miami, they offer pressure washers at some of the car washes and I've seen a few people not be able to start their cars after using them.
Burning Brakes
Joined: Oct 2004
Posts: 1,075
Likes: 570
From: Bowmanville, Ontario, Canada
Personally, I would never use a pressure washer on the engine bay. High pressure can get past the electrical seals. Garden hose is what I would use. Big one is covering the alternator. Your best bet is to watch a bunch of different YouTube videos from pros to see what they do/recommend.
Thread Starter
Burning Brakes
Joined: Apr 2018
Posts: 886
Likes: 493
Personally, I would never use a pressure washer on the engine bay. High pressure can get past the electrical seals. Garden hose is what I would use. Big one is covering the alternator. Your best bet is to watch a bunch of different YouTube videos from pros to see what they do/recommend.
Burning Brakes
Joined: Jun 2018
Posts: 756
Likes: 172
From: SC
On a side note, this is the best engine bay cleaner I have ever used. It is expensive, but it does the job and leaves no spots if rinsed well with a garden hose sprayer.
P21S 13001B
At a minimum, cover the alternator with a plastic bag from the grocery store.
P21S 13001B
At a minimum, cover the alternator with a plastic bag from the grocery store.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Administrator
Joined: Mar 2001
Posts: 368,390
Likes: 24,792
From: In a parallel universe. Currently own 2014 Stingray Coupe.
C7 of the Year - Modified Finalist 2021
MO Events Coordinator
St. Jude Co-Organizer
St. Jude Donor '03 thru '26
NCM Sinkhole Donor
CI 5, 8 & 11 Veteran
Personally, I would never use a pressure washer on the engine bay. High pressure can get past the electrical seals. Garden hose is what I would use. Big one is covering the alternator. Your best bet is to watch a bunch of different YouTube videos from pros to see what they do/recommend.
Melting Slicks
Joined: Feb 2018
Posts: 2,184
Likes: 1,049
From: North Texas
I usually just use a hose end sprayer with some Dawn liquid soap.
Low pressure and cleans well.
Let it set for a few minutes and then rinse it off well,
Blow dry with a leaf blower about 80%.
Spray engine compartment with Meguires Ultra Detail spray, blow it around again with the leaf blower to help spread the detailer and then just let it dry.
Looks just like new.
Low pressure and cleans well.
Let it set for a few minutes and then rinse it off well,
Blow dry with a leaf blower about 80%.
Spray engine compartment with Meguires Ultra Detail spray, blow it around again with the leaf blower to help spread the detailer and then just let it dry.
Looks just like new.
Pro
Joined: May 2022
Posts: 578
Likes: 426
From: Bay Area
”Only dust“…
No way I’d take any sort of running water directly to the motor for just dust. I drenched a hand towel and wiped everything off by hand. Simple. And it was a lot faster because I didn’t have to pre-prep anything or do any drying afterwards.
I used to steam clean and “power wash” engines for Shell Oil back in the 80s. No way I do that to these motors today.
Too many electronics now.
Unless you get an oil change and somebody forgot to put the cap back on…it’s really not necessary. (That happened to me once)
OR if somebody decided to take the car that they’re selling to a dealer out on a muddy road and spin donuts and get mud sentiment in the engine compartment. (That happened to me once as well.)
It’s funny that people are overly scared to buy a flood damaged Corvette… but yet they’re not afraid to take an open hose to the most sensitive part of it.
Using a hose for the engine compartment for only dust reminds me of Tim Allen wanting to “duck tape the small **** down“ so he can bust out a leaf blower to clean the house.
No way I’d take any sort of running water directly to the motor for just dust. I drenched a hand towel and wiped everything off by hand. Simple. And it was a lot faster because I didn’t have to pre-prep anything or do any drying afterwards.
I used to steam clean and “power wash” engines for Shell Oil back in the 80s. No way I do that to these motors today.
Too many electronics now.
Unless you get an oil change and somebody forgot to put the cap back on…it’s really not necessary. (That happened to me once)
OR if somebody decided to take the car that they’re selling to a dealer out on a muddy road and spin donuts and get mud sentiment in the engine compartment. (That happened to me once as well.)
It’s funny that people are overly scared to buy a flood damaged Corvette… but yet they’re not afraid to take an open hose to the most sensitive part of it.
Using a hose for the engine compartment for only dust reminds me of Tim Allen wanting to “duck tape the small **** down“ so he can bust out a leaf blower to clean the house.
Tech Contributor
Joined: Oct 1999
Posts: 41,058
Likes: 9,820
From: Charlotte, NC (formerly Endicott, NY)
I use a spray bottle filled with a 50/50 mix of Simple Green and water to soak the engine and engine compartment. I don't bother covering the alternator (I have been using this method for over 30 years), Once I have everything covered in the solvent, I let it sit for 5 or 10 minutes and then use a garden hose with an adjustable spray head set to a gentle spray and rinse everything off. Once all of the solvent is gone, I start the engine, close the hood and let the engine idle for about 20 minutes. In that amount of time, the engine gets hot enough to evaporate all of the remaining water. The Simple Green gives the hoses a nice satin look and the rest of the engine and engine compartment will be clean. Simple Green is biodegradable, so it can drain into the sewer system.
Bill
Bill
7th Gear
Joined: Apr 2025
Posts: 7
Likes: 1
I have used the HP car wash for 50 yrs cleaning engine bays. Just make sure spray is hot soapy water on hot engine block, then use the spot free to rinse for spot free clean engine bay. You do not need cover anything up, just don't concentrate spray in critical areas. Think about it, when it rains water does get into the engine bay maybe not the concentration of a HP spray but they are designed to withstand water. As for seals on electrical connections, they are 10 times better then they were in 70's 80,s ect. The old distributor cars would sometimes get moisture in cap and not start. A quick shot of WD in cap, they would fire right up.