Post by rusty on Apr 7, 2009 22:15:34 GMT 1
;D I found my fan had stopped working, and did the following to sort it out, and thought that others may find it useful.
If you find that the cooling fan stops working, rather than payout for a new one or second hand one try the following first.
First try the power supply by disconnecting the radiator sensor lead and test for voltage with a multimeter it with the ignition on, if it does show voltage your have circuit, this may be a seized motor.
If there is no voltage check the supply to the fan motor, if there is voltage in but not out it is likely that the brushes are stuck.
To check/rectify these problems, remove the rad and fan assembly.
Mark the position of all the different parts as they come apart, to ensure they go back together in the correct order.
Remove the fan mounting assembly from the rad, this is 3 screws, note the wiring run positons and the earth point.
Remove the fan and motor from the frame work, 3 nuts.
Remove the fan from the motor, 1 nut.
Find the motor back cover cover retaining screws, these are small crosshead and will probably be a bit corroded, so go careful do not wreck them.
Carefully prise off the back cover, it is beter if you can run a sharp blade round the edge first, to release it, when it comes off there could well be rust on the back of the cover and the rotor, this is the rotating part, this can be removed by gently scrapping/brushing the corrosion off.
Carefully push the fan shaft through the front part of the cover, this will release the rotor from the cover.
Inside the cover you will see two small rectagular pieces fixed to the cover, inside these are the spring loaded brushes, these can stick inside the rectangular mountings, if the brushes are not free to move in and out freely, then soak in WD40 or similar overnight,
gently work the brushes in and out of the holders, this may involve some gentle tapping of the case and pressing in with a soft wood or plastic tool, when they are free move on to the next stage. If you damage the brushes you are in need of a new motor.
On the back of the rotor you will find the armature, this looks like strips of copper round the shaft, these line up with the brushes.
This can be cleaned up to remove any carbon build up with a cloth and metal polish, DO NOT scrape, file or use sandpaper etc, you will destroy it and end up buting a new motor.
While it is apart now is the best time to lube the bearing that the fan rotor goes through.
When reassembling take great care when fitting the rotor into the casing, it has to go in at slight angle to push the bushes into the holder.
When reassembling it all again keep it all clean and seal it up to prevent water ingress again.
before fully rebuilding everything, once the motor is rebuilt put power onto the connections from a battery to ensure it runs properly.
If any parts are beyond repair you have not lost anything by trying, as if this is the case you would still need a new motor assembly.
If you need help send me a PM and if I can I will help
If you find that the cooling fan stops working, rather than payout for a new one or second hand one try the following first.
First try the power supply by disconnecting the radiator sensor lead and test for voltage with a multimeter it with the ignition on, if it does show voltage your have circuit, this may be a seized motor.
If there is no voltage check the supply to the fan motor, if there is voltage in but not out it is likely that the brushes are stuck.
To check/rectify these problems, remove the rad and fan assembly.
Mark the position of all the different parts as they come apart, to ensure they go back together in the correct order.
Remove the fan mounting assembly from the rad, this is 3 screws, note the wiring run positons and the earth point.
Remove the fan and motor from the frame work, 3 nuts.
Remove the fan from the motor, 1 nut.
Find the motor back cover cover retaining screws, these are small crosshead and will probably be a bit corroded, so go careful do not wreck them.
Carefully prise off the back cover, it is beter if you can run a sharp blade round the edge first, to release it, when it comes off there could well be rust on the back of the cover and the rotor, this is the rotating part, this can be removed by gently scrapping/brushing the corrosion off.
Carefully push the fan shaft through the front part of the cover, this will release the rotor from the cover.
Inside the cover you will see two small rectagular pieces fixed to the cover, inside these are the spring loaded brushes, these can stick inside the rectangular mountings, if the brushes are not free to move in and out freely, then soak in WD40 or similar overnight,
gently work the brushes in and out of the holders, this may involve some gentle tapping of the case and pressing in with a soft wood or plastic tool, when they are free move on to the next stage. If you damage the brushes you are in need of a new motor.
On the back of the rotor you will find the armature, this looks like strips of copper round the shaft, these line up with the brushes.
This can be cleaned up to remove any carbon build up with a cloth and metal polish, DO NOT scrape, file or use sandpaper etc, you will destroy it and end up buting a new motor.
While it is apart now is the best time to lube the bearing that the fan rotor goes through.
When reassembling take great care when fitting the rotor into the casing, it has to go in at slight angle to push the bushes into the holder.
When reassembling it all again keep it all clean and seal it up to prevent water ingress again.
before fully rebuilding everything, once the motor is rebuilt put power onto the connections from a battery to ensure it runs properly.
If any parts are beyond repair you have not lost anything by trying, as if this is the case you would still need a new motor assembly.
If you need help send me a PM and if I can I will help
