the small fan behind the cooler near the coils has stopped running
Are you serious? WOW! About as simply put as one could put it.
Is it a freezer or a cooler?
EDIT: My former response deleted due to its remarkably flippant context.
This action requires a licensed refrigeration person due to the fact that the condenser has to be relocated to repair or replace the motor.
First is to determine if the bearings are ok to just re-lube because the condenser wasn't maintained and the motor overheated constantly. There by drying out the oil. Or, if it has run enough years to actually wear out the bearing. The motor is a cast iron shunt wound either 6 or 9 watt on a pedestal base. If the bearing is loose enough so that the shaft can be raised up and down, the motor is done.
Most problems come from heat coking the lubricant in the sleeve bearing.One can usually poke a hole in the aluminum seal cap on the back top and with a zoom spout oilier lubricate the felt for the bearing. I keep a scratch awl in my tool bag just for that.. now wait for the oil to penetrate and manually keep turning the fan. it will get free after a bit. Make sure to force the fan shaft forward and backward as you turn to help the oil get all the way in and break out any carbon buildup inside the bearing. Now add power and it should run for a bit. Order a new motor for down the road, as it will be coming back in 2 to 36 months depending on how tight it got and if the condenser is kept clean
Be aware that the time for freeing and lubing can sometimes equal the cost of the motor.
Did you check for voltage to the fan? Are the fan blades intact? Oh wait... No your motor is shot, probably that;s it.
You could try The Bear's advice up here, might do it. I have salvaged bearings and made them run for months, takes time but if its all you can do to keep on going. It might be worth it. Definetley get a new fan either way.
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