Myth or true and actually safe to do???

Question

i have heard that people put water over their engines. is this true and safe? as in warm in winter to preheat it and cold in summer to cool it down or if overheating.
i thought it would be really dangerous with all the wires and connectors inside there, i mean the battery cant be safe to get wet can it? any info on what actually happens if i headr wrong would be great.

Answer 1

All electrics in an engine bay should be fully insulated and waterproofed. The engine actually gets pretty wet when you drive in rain so the electrics have to be able to cope. Steam cleaning an engine is very similar as that uses water too. If the insulation on any of the electrics is dodgy you will soon stall in any wet weather, which is the most common cause of breakdown when it is raining.
I have not heard of putting water over an engine for heating/cooling purposes, but it should be safe to do if your electrics are all intact.

Answer 2

I have the same...But never tried it. After all, being metal an engine would require a lot of warm water to preheat it. Also, warm water freezes faster than cold water, so wouldn't be of any real use... Bottom line --waste of water.Water on an engine isn't too much of a problem. it won't hurt the battery, but if it's hard enough to get the distributor and plug wires soaked, it can keep an engine from starting or cause misfiring. Example, driving through a deep pool of water will cause stalling. Personally, I wouldn't think of trying it...

Answer 3

I'll say myth and not safe to do. In fact, you could do some harm to the engine. The engine is cooled by the coolant in the radiator. The water on the engine could short out some of your electronics and wiring. If the engine is overheating, then you can spray water on the radiator to help cool the coolant more and reduce the heat. Turning off the AC will also help.

Only spray water on the engine when it is cool. Finally, in the winter, you don't need to be spraying water in the engine compartment and then run the possiblility of it freezing in the area where you park your car. good luck.

Answer 4

Never, but never run cold or even slightly warm water over a hot engine. This can break the metal through "thermal shock". The electrics are a very secondary consideration in this case. Tepid water over a cold engine may be OK, (electrics aside) but it depends on the temperature difference. You could fracture the metal of a very cold engine with hot water too. Most modern cars have so much plastic under the engine cover that you can't actually see the engine anyway. I would not consider this.

Answer 5

Driving through the desert once, my car started overheating so I watered down the radiator itself. That helps a lot as it does when it starts raining and your car is overheating. The battery will not be affected in any direct way by water on it, although you should keep a clean battery surface so that small currents can't flow across the top of the battery from terminal to terminal. Yes, getting water into the wrong places especially over the top of the engine can keep a car from running or cause it to run very poorly once it starts. For example if you get water or coolant down into the spark plug wells, it shorts out the spark.

Answer 6

If the engine is overheating - no. The best way to cool down a overheating engine is to run water over the radiator while it is running then shut it down. DO NOT ADD COLD WATER in the radiator while the car is overheated.
I've gone to the car wash many times to wash engines (pre 1995) in warm water. I've also had to take some WD-40 to and a rag to dry out the distributor cap so it would start. I've washed from the windshield to the grill and from wheel to wheel. I do not take off or spray directly into the air cleaner housing. I have not, tho, washed one without a distributor . . .

Answer 7

Myth. The only time that's been remotely near done is when the engine's severely hot and it needs to be cooled quickly - rally mechanics will gently pour water over the outside of the radiator while the engine's running. That's only because they need to get the car turned around & out again within severe time constraints & they're prepared to take the risk of thermal shock.

Answer 8

From my long experience in the past of washing the engine in my car. I have found out that if you do pour water on your engine you must do it when the engine is cool and amke sure above all else to cover the alternator with a plaxstic bag.
It is very important to make sure the alternator is covered all the way.

Answer 9

I think someone's pulling your leg! Electrical components under the bonnet may be splash proof, but I wouldn't go pouring water anywhere near the ECU, ABS unit, battery, alternator etc.
Also, if you pour cold water at say 10C onto an overheating engine at 180C, you'll almost certainly crack the head or block due to the sudden temperature change.

Answer 10

It is perfectly acceptable to add cold water to the radiator when the engine is running as the water as instantaneously circulated and cannot crack the block, some vehicles incorporate the oil cooler in with the radiator, to keep the oil at a realistic temperature, pouring cold water over a hot block will run the risk of causing it to crack, as cast iron does not like varying temperatures. if you heat a metal from one side and cool it from their other you will invoke stress which normally relives itself by demolishing the medium.