Cooling your engine down with fans

[bradleyheathhays]

This may sound like a stupid question, as I'm prone to ask sometimes. But...I drive a '96 Cherokee with the inline 4.0 non-interference engine and it doesn't like driving in the heat so much. Since I'm a car down right now I'm driving it a LOT more than I used to. After a lot of driving in this hot weather it starts slower, but still starts and runs ok.

So to help it out I've been raising the hood and putting 2 box fans right on top of the engine to help it cool. I hadn't thought about it but my Mom asked if cooling it down too quickly could be bad for the engine. And since I don't know I thought I'd ask here.

Any harm in using my method to cool an engine down much more quickly than normal?

[GeoffR Gadsden]

Trying to put simply the internal combustion engine (ICE) is an air pump, using expansion and contraction of the air the piston inside the engine moves the connecting rods, in turn rotating the crankshaft thru the gear box to the drive wheels. We use heat to expand the air inside the cylinder, we use valves to allow the air I and out of the cylinder in time for the piston movement.

Metal is used in the manufacture of most ICE motors. Metal has a thermal operating limit, as therefore the temperature needs to be controlled with in limits. Consequently we have a engine cooling system, usually air eg many motor bike or lawnmower engines, or water cool (Radiator) as in most motor car engine, as is your case.

My thoughts on your problem is the engine has suffered heat stress at some point. I would check the cylinder compression and the water cooling system to make sure the are with in the manufactures specification. This will highlight why you are having a problem. you also need to ensure the water thermostat is working correctly. Hope this helps.

[stumps]

no, it wont hurt

 

[XWrench3]

absolutely not. that method of cooling is just fine.  in the past, i have sprayed cold water across the radiator of a v-8 engine (with it idling) because it was overheating. no damage in the couple of times i have done that. but that was in the OLD days, when engines were made heavy.  i would not recommend doing so now unless it was an emergency. 

[bradleyheathhays]

Right on thanks for the advice.  I don't think it's running uncharacteristically hot right now.  It's had this slightly stalled start behavior before during the rare times I've had to run it as much as I am now.  I'm just seeing it more now because of how much I'm using it right now.