3.4 overheating
06-19-2011, 09:01 AM
#21
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So after you change the motor and it still overheats, fix the plugged radiator and/or bad fan clutch so you don't ruin motor #2. As far as replacing the motor tips, take lots of pics and notes of the wiring routing.
06-21-2011, 07:43 PM
#22
btw the fan clutches work based on a valve and friction disk system that takes advantage of the hydrodynamic drag of a 300w silicone based fluid, the valve is activated by the by-metallic spring located on the front of the clutch as the temperature rises the spring changes shape and turns the valve in the center allowing the fluid to complete a flowing path through the friction disks thus engaging the fan, then the spring cools down the valve closes and the fluid can no longer flow allowing the fan to slip....... so only a few failure modes exist that im aware of
1. the fluid leaks out very common, fan will not engauge at startup when its the case
as it normally pools in the bottom half of the clutch while the motor is shut down.
2. the valve sticks or the spring looses its springiness , in this mode the fan works only momentary at startup, or at partial power, at peek heat because it only opens a fraction, very hard to diagnose, but generally with Toyotas if its not a stuck thermostat or an obviously contaminated and corroded radiator this is the problem
3. the bearing fails (locking the fan engaged all the time)
option when you have no money.
you can't just pack the clutch with grease and expect it to replace the leaked silicone oil as grease is only about 80w despite its congealed appearance, it is hydrogenated to make it appear as it is, however you can order replacement oil and seals from toyotas parts counter, short of this I doubt you can find anything high enough viscosity to replace the oil at your local store, at least i couldn't, so to get myself through a ruff summer once i replaced the fluid with polyester resin and hardener to basically seize the thing solid, ofcourse i had already destroyed it on the side of the road by placing cardboard between the friction disks and screwing the thing back togather, got me home but started slipping again in afew days,
cheers
1. the fluid leaks out very common, fan will not engauge at startup when its the case
as it normally pools in the bottom half of the clutch while the motor is shut down.
2. the valve sticks or the spring looses its springiness , in this mode the fan works only momentary at startup, or at partial power, at peek heat because it only opens a fraction, very hard to diagnose, but generally with Toyotas if its not a stuck thermostat or an obviously contaminated and corroded radiator this is the problem
3. the bearing fails (locking the fan engaged all the time)
option when you have no money.
you can't just pack the clutch with grease and expect it to replace the leaked silicone oil as grease is only about 80w despite its congealed appearance, it is hydrogenated to make it appear as it is, however you can order replacement oil and seals from toyotas parts counter, short of this I doubt you can find anything high enough viscosity to replace the oil at your local store, at least i couldn't, so to get myself through a ruff summer once i replaced the fluid with polyester resin and hardener to basically seize the thing solid, ofcourse i had already destroyed it on the side of the road by placing cardboard between the friction disks and screwing the thing back togather, got me home but started slipping again in afew days,
cheers
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