Is washing your engine at the car wash a good idea
- Thread starter jow
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Snesley Wipes
New member
Powerwashing from a few feet out may be ok. Just make sure your engine is ON when your doing it.
Snes
Snes
Tucson4runner
New member
Can you explain that for me. I've heard it before but never got the reason why
NJshadow93
New member
I actually heard this is the worst thing to do. This is because the cold water hitting a hot engine can cause some serious damage, such as cracking it. I could be wrong.
snowbrdr033
New member
Yeah, I've always heard that it needs to be cold, or you can crack the manifold or other parts. I've simply used a "light" wash from the hose with some simple green or another easy cleaner and steer clear of the fuse box or other important electronic components.
Tucson4runner
New member
But there are electrical components everywhere! Is there some way to "waterproof" the connections and fuse box?
CookieRoe
Senior Member
no.................
Best thing to do is to AVOID power washing the motor at a car wash. Why? The engine is hot. Cold water and an engine cranking along at around 180-200 degrees is NOT a good idea. Notice with most degreasers, it says to spray on COLD engine, wait 5-10 minutes, then spray.
Clockwork: 100% correct on spraying engine down with "shower" setting. Remember guys, there are all kinds of electronics plugs on the engine, air intake, master cylinder, etc. Do you really want to high pressure wash them down and risk damage? Go ahead at your own risk. Chances are nothing will happen, but you do open the door for BS to occur.
When I used to detail cars (my entrepreneurial endeavors when I was young), we never would touch the engine until it was cold.
Best thing to do is to AVOID power washing the motor at a car wash. Why? The engine is hot. Cold water and an engine cranking along at around 180-200 degrees is NOT a good idea. Notice with most degreasers, it says to spray on COLD engine, wait 5-10 minutes, then spray.
Clockwork: 100% correct on spraying engine down with "shower" setting. Remember guys, there are all kinds of electronics plugs on the engine, air intake, master cylinder, etc. Do you really want to high pressure wash them down and risk damage? Go ahead at your own risk. Chances are nothing will happen, but you do open the door for BS to occur.
When I used to detail cars (my entrepreneurial endeavors when I was young), we never would touch the engine until it was cold.
Snesley Wipes
New member
Service guy at the dealership told me to do it while its on because if you happen to get some water where it's not supposed to be, you may not be able to restart it if it's already off. I never had any issues either with the engine on or off in my years of spraying. I just used common sense not to blast it too close so I don't cut into anything with that pinpoint waterstream.
The powerwashes I have used have always had hot water coming out of them. I imagine in theory cold water and a hot engine could equal a crack, but I would think you would have to have ice cold water and an almost submersible amount of it.
Personally, I have never had any negative experiences with powerwashing my engine.
RonMAIDEN
Super Moderator
You will not crack your block with cold car wash water since it would have to be real cold and alot of it would have to hit the engine at once. The pressure wash around here is heated in the winter so the remote chance of an engine block cracking became even more remote.
I do occasionally wash my engine at the car wash after muddy off roading and I simply let the engine cool a few minutes and then I spray everything down with some Gunk Engine Brite and use the light pressure being careful to avoid direct spray on electrical components and maybe a little harder pressure on the lower parts of the engine but still use the hard pressure sparingly.
I've been washing engines the same way for 20 years and never had a problem.
I hate working on a dirty motor and a dirty motor runs hotter than it should.
I do occasionally wash my engine at the car wash after muddy off roading and I simply let the engine cool a few minutes and then I spray everything down with some Gunk Engine Brite and use the light pressure being careful to avoid direct spray on electrical components and maybe a little harder pressure on the lower parts of the engine but still use the hard pressure sparingly.
I've been washing engines the same way for 20 years and never had a problem.
I hate working on a dirty motor and a dirty motor runs hotter than it should.
From my 45 years of rebuilding/wrenching/ power-washing I have never had crack or serious problem washing it hot, running or not. My nerves are not what they use to be and I always felt it was a slight risk.
1. Washing hot not running would cause condensation in the distributor and not start until you dried the inside. I doubt you would have that problem today with the electronics and no distributor.
2. I always stayed away from the alternator/electronics, exhaust manifold, worked at a dist except oily areas.
3. I have the Simple Green Etc and that will be my choice but always wondered what did the Dealers do.
jow
1. Washing hot not running would cause condensation in the distributor and not start until you dried the inside. I doubt you would have that problem today with the electronics and no distributor.
2. I always stayed away from the alternator/electronics, exhaust manifold, worked at a dist except oily areas.
3. I have the Simple Green Etc and that will be my choice but always wondered what did the Dealers do.
jow
williamZ
New member
Spraying water on electrical connections with it running is not good at all!
Spray the bay down with Simple Green.
Brush with soft brush if needed.
Rinse off with garden hose or nozzle.
This is the most important part-
Use compressed air to blast your engine and electrical connections until they are dry. You can also use a good leaf blower. You do not want water to sit in your electrical connections. It can lead to problems.
Spray the bay down with Simple Green.
Brush with soft brush if needed.
Rinse off with garden hose or nozzle.
This is the most important part-
Use compressed air to blast your engine and electrical connections until they are dry. You can also use a good leaf blower. You do not want water to sit in your electrical connections. It can lead to problems.
simple green
I agree spray cold water on a hot engine drops the temperature too quickly and may cause cracking, etc.
What I do is spray simple green on the engine while it is still warm, not super hot though. The reason for this: spray a few mist of simple green is no way going to drop that quick to cause any damage. When the engine is warm, oil and gunk are more fluid and can be cleaned a lot easier.
So, the bottom line, warm engine and mist with Simple Green. It's that simple. lol
I agree spray cold water on a hot engine drops the temperature too quickly and may cause cracking, etc.
What I do is spray simple green on the engine while it is still warm, not super hot though. The reason for this: spray a few mist of simple green is no way going to drop that quick to cause any damage. When the engine is warm, oil and gunk are more fluid and can be cleaned a lot easier.
So, the bottom line, warm engine and mist with Simple Green. It's that simple. lol
CookieRoe
Senior Member
Just throwing it out there.......................
Hey guys,
This is turning into a "no clear winner" thread. BUT, I will throw this out:
When I used to clean my wheels with Simple Green on my Grand Cherokee, the clear coat would start to peel and separate after a few months. The stuff also dried the crap out of my hands. Powerful stuff. So, if you are going to apply simple green to the engine bay, apply Amour All on the plastic/rubber stuff in the engine bay. I no longer use Simple Green. I do the following:
1) Cover up the Battery and fuse box (anything with wires/plugs exposed)
2) Degreaser, "shower" setting on the garden hose on cold engine
3) Apply cleaner wax to the painted areas of the engine bay
4) Armor All all black plastics/hoses.
My engine bay is in showroom condition BTW.
Hey guys,
This is turning into a "no clear winner" thread. BUT, I will throw this out:
When I used to clean my wheels with Simple Green on my Grand Cherokee, the clear coat would start to peel and separate after a few months. The stuff also dried the crap out of my hands. Powerful stuff. So, if you are going to apply simple green to the engine bay, apply Amour All on the plastic/rubber stuff in the engine bay. I no longer use Simple Green. I do the following:
1) Cover up the Battery and fuse box (anything with wires/plugs exposed)
2) Degreaser, "shower" setting on the garden hose on cold engine
3) Apply cleaner wax to the painted areas of the engine bay
4) Armor All all black plastics/hoses.
My engine bay is in showroom condition BTW.
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RonMAIDEN
Super Moderator
You do want to dilute the Simple Green but I still like an engine degreaser like the Gunk stuff. As far as wheels I never use anything except stuff for wheels and never use harsh cleaners on them and Simple Green is one.
All this talk over engine cracking from a pressure washer but has anybody actually known an engine to be destroyed doing this? I highly doubt it and I've never even read anything about it being a real issue so powerwashing an engine and cracking is a myth more than fact. Avoiding electronics is a good idea tho'.
Plus in colder states that carwash water will be quite warm to prevent freezing so the issue isn't even there in colder temps.
All this talk over engine cracking from a pressure washer but has anybody actually known an engine to be destroyed doing this? I highly doubt it and I've never even read anything about it being a real issue so powerwashing an engine and cracking is a myth more than fact. Avoiding electronics is a good idea tho'.
Plus in colder states that carwash water will be quite warm to prevent freezing so the issue isn't even there in colder temps.
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I dont think engine itself would crack, but there are seals that may start to leak. Different materials have different expansion and contraction rate, when the temperature drops too drastically, some materials will react quicker (contract quicker). this will cause some seals to leak. If the temperature changes grandually, then the difference in the rate of expansion/contraction is smaller.
12guns
New member
Yes, you can use dielectric grease on all the plugs and connectors. It's the same thing 4wheeler riders use to "waterproof" their wheelers.
I've washed engine bays with a pressure washer all my short life (16 years of driving) and never had any issues. Well, I take that back, I had a shorted spark plug wire that caused a "miss" when it got wet, but that happened even in the rain. I don't think cold water would ever crack a block. I've never heard of it happening, furthermore would it not be just like hitting a deep puddle on the road, which happend all the time?
Bottom line, don't do it if you're that worried about it. As for me, I just washed mine off the other day, pressure washed with soap and everything.
If you are worried, just use some spray on tire cleaner, no rinsing needed!
Radial GT
New member
Connectors are water proof, just don't spray really close and you won't have any problems. Have you seen the mud pits these trucks go into?? The engine can run underwater.
If your at a carwash, most we have here in minnesota have warm water that comes out so not too much to worry about cracking engine blocks. Yes the obvious has been mentioned don't spray right at the alternator or the exhaust manafolds. Otherwise really shouldn't be an issue.
:boxer:
If your at a carwash, most we have here in minnesota have warm water that comes out so not too much to worry about cracking engine blocks. Yes the obvious has been mentioned don't spray right at the alternator or the exhaust manafolds. Otherwise really shouldn't be an issue.
:boxer:
