Wipe down or spray engine... who's right?
Team Owner
Joined: Mar 2001
Posts: 25,889
Likes: 7
From: Virginia Beach
CI 3-5-6-7-8 Veteran
Are we saying all water is bad, or are we saying pressure washing is bad?
I've never clleaned under my hood and it's a little dirty. I wipe it down w/ a damp rag and blow it out with my compressor often, but I'd like to do it really nice.
I was thinking 2:1 water:simple green on a mildly warm motor, let sit 5 minutes, then rinse off w/ free flowing hose. Then immediately follow up with my compressor to blow all water out of all areas, then try w/ a towel, then start the car and let it run to temp.
Evit-Twin and those in the know... is this bad!?! My main concern is the accumulated dust etc around the coil packs and some parts of the motor.
I've never clleaned under my hood and it's a little dirty. I wipe it down w/ a damp rag and blow it out with my compressor often, but I'd like to do it really nice.
I was thinking 2:1 water:simple green on a mildly warm motor, let sit 5 minutes, then rinse off w/ free flowing hose. Then immediately follow up with my compressor to blow all water out of all areas, then try w/ a towel, then start the car and let it run to temp.
Evit-Twin and those in the know... is this bad!?! My main concern is the accumulated dust etc around the coil packs and some parts of the motor.
Drifting
Joined: Jul 2003
Posts: 1,647
Likes: 2
From: Peoples Republik of Kalifornia Ka
Originally Posted by Evil-Twin
The worst possible thing you can do is pressure wash your engine... there have been hundreds of cases where the knock sensors get shorted out, because of this... It can be very costly to pressure wash your engine.. My engine looks as good or better than the day I bought it.. IT has never seen water.... I use compressed air and wipe everything down with quick detailer.
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Joined: Aug 2002
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Tech Contributor
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St. Jude Donor '05-'06-'07-'10
Originally Posted by Cobra4B
Are we saying all water is bad, or are we saying pressure washing is bad?
I've never clleaned under my hood and it's a little dirty. I wipe it down w/ a damp rag and blow it out with my compressor often, but I'd like to do it really nice.
I was thinking 2:1 water:simple green on a mildly warm motor, let sit 5 minutes, then rinse off w/ free flowing hose. Then immediately follow up with my compressor to blow all water out of all areas, then try w/ a towel, then start the car and let it run to temp.
Evit-Twin and those in the know... is this bad!?! My main concern is the accumulated dust etc around the coil packs and some parts of the motor.
I've never clleaned under my hood and it's a little dirty. I wipe it down w/ a damp rag and blow it out with my compressor often, but I'd like to do it really nice.
I was thinking 2:1 water:simple green on a mildly warm motor, let sit 5 minutes, then rinse off w/ free flowing hose. Then immediately follow up with my compressor to blow all water out of all areas, then try w/ a towel, then start the car and let it run to temp.
Evit-Twin and those in the know... is this bad!?! My main concern is the accumulated dust etc around the coil packs and some parts of the motor.
I know that several folks use the method you describe. I can't for certain say that all water would be bad. A warm motor will help, the least water pressure you can use will help and a more perpindicular angle with the hose (ie. flowing from the top down rather than trying to angle the spray into the nooks and crannies will help). I've never used any water under the hood of my car and I've never had troubles but I can't draw the conclusion from that that no water means no problems for everyone else. Like anything else, the more you can keep on top of it, the easier it is to keep clean. My engine looks brand new and for a 59,000 mile car It looks damn impressive if I do say so myself.
The posts that Bill and Ed made make it pretty clear to me that pressure washing should not be considered and those that have used it are more lucky than good if they have not had issues.Paul
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I've been able to keep mine looking good with just a wipe down and the occasional use of a little Simple Green on a rag. I personally would not use a power washer on my engine bay - too many electronics.
Drifting
Joined: Oct 2005
Posts: 1,507
Likes: 7
From: Palmetto FL
St. Jude Donor '07
Originally Posted by Evil-Twin
The worst possible thing you can do is pressure wash your engine... there have been hundreds of cases where the knock sensors get shorted out, because of this... It can be very costly to pressure wash your engine.. My engine looks as good or better than the day I bought it.. IT has never seen water.... I use compressed air and wipe everything down with quick detailer.
Same here - no water. I use a damp cloth if needed, then dry and detail spray. Engine compartment looks as clean as the interior/exterior. Top half anyway 
Thread Starter
Team Owner
Joined: Jan 2006
Posts: 58,551
Likes: 95
From: The warm part of Anger Island
St. Jude Donor '09
WOW 
... MEMORIES! This was one of my first threads I ever posted.
I decided to go with a wet wash. With the engine slightly warm and allt he intakes and wot-not plugged/covered with plastic baqgs and hose clamps, I soaked it in a mild water/Simple Green solution. Then with the REGULAR HOSE AND THE FAUCET TURNED ON ABOUT HALF WAY, I rinsed from top to bottom trying to keep the stream perpendicular to the motor. I was able to most of the time. After a good bath and rinse, I blew the compartment off witht he air hose from top to bottom and then wiped all the plastics off with a clean chamois. The finishing touch was some Mother's Back-to-Black and it looks all
now.
Now that is done, I followed some member's advice and bought a Clifornia Duster. This works well when combined with the air hose.
John
... MEMORIES! This was one of my first threads I ever posted.I decided to go with a wet wash. With the engine slightly warm and allt he intakes and wot-not plugged/covered with plastic baqgs and hose clamps, I soaked it in a mild water/Simple Green solution. Then with the REGULAR HOSE AND THE FAUCET TURNED ON ABOUT HALF WAY, I rinsed from top to bottom trying to keep the stream perpendicular to the motor. I was able to most of the time. After a good bath and rinse, I blew the compartment off witht he air hose from top to bottom and then wiped all the plastics off with a clean chamois. The finishing touch was some Mother's Back-to-Black and it looks all
now.Now that is done, I followed some member's advice and bought a Clifornia Duster. This works well when combined with the air hose.
John
Race Director
Joined: Apr 2004
Posts: 16,135
Likes: 5
From: Newberry FL
Cruise-In VIII Veteran
St. Jude Donor '07
Originally Posted by GeorgeZNJ
Let engine warm up, with engine still running spray on degreaser/detergent, let soak fo 10-15 minutes. Pressure wash entire bay. No problems whatsoever. Car has just over 24K, and when people see the engine bay they ask if I ever use the car.
Same here. Never had a problem, just be careful.
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