A suggestion to all who have cooling systems with fan clutch installed...
CHECK THEM!
It is a very simple process, whenever the hood is open for maintenance such as the oil change, simply take your finger and touch one of the blades and do 2 things.
Try to push it "sideways", push in the same direction as the shaft, so front mounted push forward/backward, side mounted push left/right to the vehicle.
ANY movement here is a fail.
Next push in the rotational direction, is should rotate smothly and with some friction, if it turns freely like a house fan, or you feel roughness it is a fail.
Takes 10 seconds of your time.
Easy to repair in the driveway, some time and a part, pain and possible blown parts on the highway.
If the first test fails the bearings are so worn the fan will wobble on the end of the shaft, considering the distance from the plane of the fan blade to the shaft bearing, and that the bearing is in a small place along with the stress placed by the belts, the fan bearings are under considerable stress and within normal design, but having the fan wobble at the distance from the small bearing area it causes the bearing to fail a lot faster than expected, and it is a gradual wear until it just gives out and fails, belts may cause shaft to wobble more allowing fan blade to touch radiator, not good, plus engine overheat possibilities.
The second test with rotation also checks the bearings, but in addition it checks the fluid coupling and the clutch, if it turns too easily then it will likely free spin when it should be better connected to the shaft.
Yes the engine is cold and the fan should free spin, but there is resistance to turning, you will know it is good or bad depending on the feel.
You also could repeat when hot, but hot parts are a pain, and the fan will have cooled enough to release by the time you test it.
Another tell tale is if the engine runns hotter when driving slow, highway speeds push the air through the radiator, slow driving needs more fan help.
You can tell by listening on a hot day, have engine at idle with AC on max and the engine will get hot and the fan activate, but the simple touch test if done on occasion usually indicates when the fan is starting to fail.
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Tony & Lori
1989 Country Coach Savannah SE
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