Washing hot/warm vehicle?

[CharlesW]

Another forum recently had someone ask a question about washing a vehicle right after driving it.
The answer given didn't really seem to address the person's question, but it did give rise to some thoughts to me.

Could this be a problem?
Obviously, spraying cold water on a hot engine would seem to be less than advisable, but....
What are some possible consequences of other hot surfaces.
1. Wheels, wheel bearings, brake rotors and calipers for instance.
2. Painted surface such as the hood.
3. What about the vehicle that has been parked in the sun? Many times the paint is hot enough to almost burn you. Does the cold water stress the paint when it is sprayed on a surface that is that hot?
It has never been a problem for me, but I have had either a shaded area or a garage to work in.

How about the warm water on cold paint in the winter?
I once worked with a woman that never scraped the ice from her windows. She poured hot water from a tea kettle on the windshield while running the wipers. Did the same thing to the rear window and side windows and wiped them with a terry towel.
I told her that was not a good thing to do because of cracking the glass. She simply said she had been doing it for years and it hadn't happened yet.

Maybe we worry too much about how heat/cold affects our vehicles.

 

[Mindflux]

The only thing I worry about is not spraying down the brake rotors or engine immediately. Fast temperature shifts can lead to fractures.

 

[sal329]

Just like Mindflux said. The brake rotors will warp when hot and then it with cold water. Hot engines and cold waters do not mix. When I worked in NJ I can not tell you how many windshields we replaced in winter from people pouring water on them, some of them get a small crack, some almost shatter and I have seen a few that popped out of the frame.

 

[Pockets]

Is it any different than driving through the rain that just appeared out of a nice hot day?? I have been sitting at a light and see steam coming from my brakes when they get wet. Or when your car is sitting in the sun and it starts to rain??

 

[Stephan]

I have well water which is very cold and I notice that on hot days when the paint has been baking in the sun if I go to wash it, the water begins to dry almost instantly and with the hard water I have I immediately get water marks on the paint.

 

[Mindflux]

Is it any different than driving through the rain that just appeared out of a nice hot day?? I have been sitting at a light and see steam coming from my brakes when they get wet. Or when your car is sitting in the sun and it starts to rain??

It wouldn't be any different if rain came down in a large stream like it does from a hose and fell directly onto the parts in question.

:lol2:

 

[Pockets]

It wouldn't be any different if rain came down in a large stream like it does from a hose and fell directly onto the parts in question.

:lol2:

I can go through some pretty big and deep puddles with my truck . I see what your saying though :redface:

 

[Mr. Clean]

It wouldn't be any different if rain came down in a large stream like it does from a hose and fell directly onto the parts in question.

:lol2:

And here I thought you were from Texas. Rain in Texas often comes down a heck of a lot faster and with equal or greater amount of pressure than a water hose.

And to the original question, I've washed cars that though they had been parked the paint's surface temps were hot enough to feel the warmth through a wash mitt or a sea sponge. No known paint damage. I would be hesitant to spray wheels that had been driven hard without a cool down period. JMO, no scientific measurements.

 

[Mindflux]

And here I thought you were from Texas. Rain in Texas often comes down a heck of a lot faster and with equal or greater amount of pressure than a water hose.

Let me know when you see rain that can be applied as quick as 4GPM to a solitary area such as a brake rotor.

:rofl

Good rain here in Austin yesterday.

 

[RyansAutoDetail]

Another forum recently had someone ask a question about washing a vehicle right after driving it.
The answer given didn't really seem to address the person's question, but it did give rise to some thoughts to me.

Could this be a problem?
Obviously, spraying cold water on a hot engine would seem to be less than advisable, but....
What are some possible consequences of other hot surfaces.
1. Wheels, wheel bearings, brake rotors and calipers for instance.
2. Painted surface such as the hood.
3. What about the vehicle that has been parked in the sun? Many times the paint is hot enough to almost burn you. Does the cold water stress the paint when it is sprayed on a surface that is that hot?
It has never been a problem for me, but I have had either a shaded area or a garage to work in.

How about the warm water on cold paint in the winter?
I once worked with a woman that never scraped the ice from her windows. She poured hot water from a tea kettle on the windshield while running the wipers. Did the same thing to the rear window and side windows and wiped them with a terry towel.
I told her that was not a good thing to do because of cracking the glass. She simply said she had been doing it for years and it hadn't happened yet.

Maybe we worry too much about how heat/cold affects our vehicles.

my easy solution:

1- get another person to help you wash the vehicle
2- if that fails get a third person to help wash and that should be enough to do a fast washing

one person rinses entire car, one does the wheels while the third person wash mitts the car with soap if not 2 people doing that task

cheers !

 

[97F1504x4]

Well i actually had a windshield crack to hell on me once when i hit it with the cold water on a very hot day. Not a pretty site or a fun experience that's for sure.

As for putting cold water on hot engine it can cause crack in the block the head and just about any other metal component.
When it comes to hot wheel bearing the water can actually be drawn into the bearing area thus destroying it at a later date due to water infiltration.
Brake can warp but there is a pretty low possibility of that unless they are blazing hot.

I actually use Ryan's idea of two people helping to wash the car. On days when i have no choice but to wash one of my vehicle in the hot sun I usually have the wife or kid hold the hose on the vehicle while i wash. Granted i get soaking wet this way but it prevents water spotting and soap drying on before i get a chance to rinse it off.