jabbahutt
|
 posted on 3/3/08 at 11:56 AM |
|
|
fan motor
Morning all
The electrical fool signing in again for more questions of a daft nature 
Tested out the cooling fan manual over ride switch last night and against all odds seeing I was involved the thing worked!! even the little warning
light came on FANTASTIC
just one small problem, the fan is mounted on the rear of the rad and I could of sworn the blade orientation etc was the right way round however the
fan is blowing air through the rad forward rather than sucking it in through the nose cone.
Can you just switch the earth and power wire over so the motor runs in the other direction? I know I need to double check the orientation of the fan
blades but if they're correct I can only think of this as a solution.
Numpty logic says yes but thought I'd check before ruining the fan.
Cheers all
Nigel
|
|
|
|
|
Mr Whippy
|
| posted on 3/3/08 at 11:58 AM |
|
|
oh oh it's him again
only kidding 
just swap the wires round, the motor will then turn the otherway. Wish all your problems were so easy
[Edited on 3/3/08 by Mr Whippy]
Fame is when your old car is plastered all over the internet
|
|
|
David Jenkins
|
| posted on 3/3/08 at 12:04 PM |
|
|
On some fans you can undo the nut holding the blades and turn them over - they are usually more efficient when turning in the correct direction.
|
|
|
jabbahutt
|
| posted on 3/3/08 at 12:09 PM |
|
|
cheers fellas, thanks for the prompt replies.
I'm aware I can swap the blades round, just need to check them before messing with the wiring.
Thanks for clarifying my fan won't burst into flames if I swap the wires over because if it could happen to me then it would.
Well that just leaves the dials to connect to the main loom after which you should all be able to rest easy in this electrical part of the forum for a
while
Nigel
|
|
|
Mr Whippy
|
| posted on 3/3/08 at 12:18 PM |
|
|
More likely it would burst into flames if not turned over, as the fan motor would stall against the wind if it came on whilst driving 
Fame is when your old car is plastered all over the internet
|
|
|
BenB
|
| posted on 3/3/08 at 12:20 PM |
|
|
It's not best practice to run the motor backwards A quick test would do no harm though. It'll run better one way than the other. Only
problem will be the fan will induce more drag in one direction than the other so you can't necessarily use fan speed alone as an indicator of
preferred direction.
Unless as well as changing polarities you flip the blade over. Then the only thing changing is the direction of motor rotation.
If you record both fan tests on a video camera (or even an MP3 recorder or something like that) when it cuts from one test to another you'll
notice an obvious pitch change if the motor is happier rotating one way or the other.
Alternatively, use a digital tacho to check the speed....
|
|
|
Schrodinger
|
| posted on 3/3/08 at 01:12 PM |
|
|
If it is meant to be a front mounted fan then you need to move it to the front of the radiator it will then be blowing the correct way, it wont
necessarily turn the other way by changing the polarity, it will depend on the motor type. As has been said you need to correct type for your
application.
Keith
Aviemore
|
|
|
jabbahutt
|
| posted on 3/3/08 at 01:47 PM |
|
|
the fan was from Car builder and states will run as either a puller or a pusher. I think the first thing to do is check the blade orientation
compared to direction of rotation.
Cheers for the help
|
|
|
bob
|
| posted on 3/3/08 at 02:03 PM |
|
|
Yep you can change blade orientaition and polarity on those fans, i changed mine from push to pull when i outed the pinto.
Originally i had the fan on the front but found it restristed air flow through the nose, since the zetec went in and i changed the rad as well (polo)
i swapped the fan over. the only difference i have noticed is the fan comes on less, but when it does it works as well pulling ans it did pushing.
|
|
|
jabbahutt
|
| posted on 3/3/08 at 02:44 PM |
|
|
Thanks Bob
I am correct that to change the blade orientation you simply remove the centre nut and the blades come out, flip them over and refit the nut?
Thanks
Nigel
|
|
|
bob
|
| posted on 3/3/08 at 03:33 PM |
|
|
Yes thats all i did with mine and just switched the wires.
|
|
|
