i was just wondering sometimes when driving slow in first gear it sounds like a fan is on loud. just wondering what this was? is it the transmition fan?

 

I get that, and just having it sit in driveway in high idle. I think it is just that the fan has caught up to the engine RPM.

 

Does the fan ever stop spinning? I didn't take a look to see if it has a clutch or not.

 

Fan never stops spinning. You got clutch.

 

Roger, so it just spins slowly and then engages the clutch when it needs to spin faster?

 

Fan clutch
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A fan clutch is a thermostatically-controlled device that exists as an integral component of the automotive cooling system. When the engine is cool or even at normal operating temperature, the fan clutch partially disengages the engine's mechanically-driven radiator cooling fan, generally located at the front of the water pump and driven by a belt and pulley connected to the engine's crankshaft. This saves power since the engine does not have to fully drive the fan.

However, if engine temperature rises above the clutch's engagement temperature setting, the fan becomes fully engaged, thus drawing a higher volume of ambient air through the vehicle's radiator which in turn serves to maintain or lower the engine coolant temperature to an acceptable level.

Most fan clutches are viscous or "fluid" couplings combined with a bi-metallic sensory system similar to that in a thermostat.

Normally fan clutches are fairly reliable, but sometimes they fail. A common symptom of fan clutch failure is overheating at idle or in heavy traffic. Bad fan clutches can also cause poor performance of the car's air conditioning system because the fan also cools the air conditioner's condenser, which is directly in front of the radiator.

Another potential symptom of fan clutch failure (always drawing air at a high rate) in a cold weather climate is that the heating system blows lukewarm air never delivering sufficient hot air.

Out of my Service Manual.
Fan Clutch Test

Spin the fan blade (8600) by hand. A light resistance should be felt. If there is no resistance or very high resistance, the minimum and maximum fan speeds must be checked as follows:
Fan Clutch Test—Minimum Speed Requirement

Use a suitable marker to mark the water pump pulley (8509), one of the fan blade retaining bolts and the crankshaft pulley (6312).
Connect a tachometer to the engine.
Install a throttle adjusting tool.
Connect the Digital Photoelectric Tachometer.
WARNING: To avoid the possibility of personal injury or damage to the vehicle, do not operate the engine until the fan blade has been first examined for possible cracks and separation.

Start the engine and run it at approximately 1,500 rpm until the normal operating temperature has been achieved.
Operate the strobe light at 4,320 rpm for 5.4L and 6.8L engines and 3600 rpm for 7.3L diesel engines, and aim it at the water pump pulley. Adjust the engine speed until the light flash and the water pump pulley mark are synchronized.
Aim the strobe light at the fan blade bolts. Adjust the strobe light until the light flash is synchronized with the marked fan blade bolt (the fan blade appears to stand still).
The fan blade speed must not be greater than 1,900 rpm on 5.4L engines and 2,000 rpm on 6.8L and 7.3L engines.
Turn the engine off.
If the fan blade speed was greater than 1,900 rpm (on 5.4L) (on diesel engines and 6.8L, 2,000 rpm), install a new fan clutch (8A616).
Fan Clutch Test—Maximum Speed Requirement

Perform Steps 1 through 5 of the Fan Clutch Test—Minimum Speed Requirement.
NOTE: The temperature of the air hitting the fan clutch should be above 96°C (205°F) for maximum fan speed.

Block off areas on each side of the radiator in the engine compartment and the front of the radiator grille (8200). This will raise the temperature of the air striking the fan clutch and should cause the fan blade to operate at maximum speed.
Place the climate control function selector switch in the MAX A/C position and the blower motor switch in the HI position.
Adjust the strobe to 4,320 rpm for 5.4L and 6.8L engines and 3,600 rpm for 7.3L diesel engines.
WARNING: To avoid the possibility of personal injury or damage to the vehicle, do not operate the engine until the fan blade has been first examined for possible cracks and separation.

Start the engine and adjust the engine speed until the strobe light flash and the water pump pulley mark are synchronized.
Aim the strobe light at the fan blade retaining bolts. Adjust the strobe light until the light flash is synchronized with the marked fan blade bolt (the fan blade appears to stand still).
If the fan blade speed is less than 3,600 rpm on 5.4L engines and 3,500 rpm on 6.8L engines, 2,850 rpm on 7.3L engines, install a new fan clutch.

 

Thanks for the information! I am pretty sure everything is in line right now.

Where did you pick up a service manual?

 

Online last year. Dug through paypal folders with no luck looking for receipt that say what place i got it from.