Bench test a fan ??

championdaddy · 25th July 2013, 20:52

Hello chaps, just was wondering if there is any way to bench test a fan ?

I recently bought a 2 speed gold resistor jobby from Jules, due to my 3 speed fan not working.

I had rebrushed a year ago, but was informed i was lucky to get a year.

Anyway........when I removed it, I decided to see what the state of the inside was.

Shockingly.......All 4 brushes were still in pretty good nick !!!

All connections were still intact too.

So Im thinking that I spent £200 on a fan when maybe the relay or something had gone ???

Can you bench test a fan ? or does it have to be connected into the proper circuit for it to work ?

HarryM1BYT · 25th July 2013, 21:24

Quote:

Originally Posted by championdaddy

Hello chaps, just was wondering if there is any way to bench test a fan ?

You can bench test them, but not being familiar with the circuit I cannot advise on how, but a word of warning....

They are an awfully powerful fan, more than capable of running amok and taking fingers off. When testing, make sure it is well lashed down and better, remove the blade. The blade just bayonet fixes onto the motor shaft.

Jules · 25th July 2013, 22:00

HI Paul
Only just seen this.
If it's still connected to the old control box, connect the large black to -ve (at plug end)

Connect large brown to +ve .

Then simply bridge the 3 output terminals of the 3 relays.
In turn should give you one speed.
Bridge 2 or 3 relays brings the other speeds in (or not as the case maybe)

Let us know your findings

lovema75 · 25th July 2013, 23:47

This is the highly technical drawing I produced when rebuilding my last fan to allow for testing off the car:

The will force the fan to run at full speed thus confirming the correct operation of the brushes.

Mike Noc · 26th July 2013, 06:53

That looks great. A wiring diagram in the style of Roobarb and Custard.

I drew this one up a few years ago for the three speed, if anyone is looking at the diesel circuit:

[IMG]

[/IMG]

Jules · 26th July 2013, 06:55

Quote:

Originally Posted by lovema75

This is the highly technical drawing I produced when rebuilding my last fan to allow for testing off the car:

The will force the fan to run at full speed thus confirming the correct operation of the brushes.

Like it .
Where's the purple wire

championdaddy · 26th July 2013, 09:00

Thanks guys......will have a go when the kids arn't around , and let you know whats occurs....if anything

lovema75 · 26th July 2013, 09:57

Quote:

Originally Posted by Jules

Like it .
Where's the purple wire

Dont think mine must have had one if its not on the diagram, although this was from some time back so only going from memory. But it worked! Wooosh!

Arctic · 26th July 2013, 13:47

Quote:

Originally Posted by Mike Noc

That looks great. A wiring diagram in the style of Roobarb and Custard.

I drew this one up a few years ago for the three speed, if anyone is looking at the diesel circuit:

[IMG]

[/IMG]

As is real time three speed four wire box like Mikes diagram above just my little bit to the thread.

As opposed to the V6 petrol in the 190 control below

lovema75 · 26th July 2013, 13:56

If I remember rightly I tested from the plug rather than the control box, could that be the difference? Or maybe more likely I just forgot the purple wire!

P.S do you think Haynes will head hunt me for my technical drawing skills?

25th July 2013, 20:52	#1
championdaddy This is my second home Mg Zt 190 Join Date: Apr 2012 Location: The FIRST Garden City....Letchworth. Posts: 6,778 Thanks: 1,243 Thanked 920 Times in 698 Posts	Bench test a fan ?? Hello chaps, just was wondering if there is any way to bench test a fan ? I recently bought a 2 speed gold resistor jobby from Jules, due to my 3 speed fan not working. I had rebrushed a year ago, but was informed i was lucky to get a year. Anyway........when I removed it, I decided to see what the state of the inside was. Shockingly.......All 4 brushes were still in pretty good nick !!! All connections were still intact too. So Im thinking that I spent £200 on a fan when maybe the relay or something had gone ??? Can you bench test a fan ? or does it have to be connected into the proper circuit for it to work ?

25th July 2013, 22:00	#3
Jules This is my second home ZT 260 SE Twilight and 10 other 75 ZT's :O Join Date: Jan 2007 Location: Conwy NORTH WALES Posts: 11,094 Thanks: 512 Thanked 1,116 Times in 763 Posts	HI Paul Only just seen this. If it's still connected to the old control box, connect the large black to -ve (at plug end) Connect large brown to +ve . Then simply bridge the 3 output terminals of the 3 relays. In turn should give you one speed. Bridge 2 or 3 relays brings the other speeds in (or not as the case maybe) Let us know your findings __________________ [SIGPIC][/SIGPIC] Newbies do now!! 1. Plenum drains..all 3 or 4 year dependent 2. Cooling fan..All speeds functioning 3. Bonnet cable divider block

26th July 2013, 06:53	#5
Mike Noc This is my second home Rover 75 CDT Manual Connoisseur SE, Rover 75 CDT Automatic Connoisseur SE & a Freelander Td4. Join Date: Jul 2009 Location: Hampshire Posts: 11,551 Thanks: 3,470 Thanked 3,119 Times in 2,247 Posts	That looks great. A wiring diagram in the style of Roobarb and Custard. I drew this one up a few years ago for the three speed, if anyone is looking at the diesel circuit: [IMG][/IMG]

25th July 2013, 23:47	#4
lovema75 This is my second home 75 Tourer CDT Join Date: Dec 2011 Location: Enfield Posts: 3,925 Thanks: 63 Thanked 431 Times in 237 Posts	This is the highly technical drawing I produced when rebuilding my last fan to allow for testing off the car: The will force the fan to run at full speed thus confirming the correct operation of the brushes.

26th July 2013, 09:00	#7
championdaddy This is my second home Mg Zt 190 Join Date: Apr 2012 Location: The FIRST Garden City....Letchworth. Posts: 6,778 Thanks: 1,243 Thanked 920 Times in 698 Posts	Thanks guys......will have a go when the kids arn't around , and let you know whats occurs....if anything

26th July 2013, 13:56	#10
lovema75 This is my second home 75 Tourer CDT Join Date: Dec 2011 Location: Enfield Posts: 3,925 Thanks: 63 Thanked 431 Times in 237 Posts	If I remember rightly I tested from the plug rather than the control box, could that be the difference? Or maybe more likely I just forgot the purple wire! P.S do you think Haynes will head hunt me for my technical drawing skills?