Strange fan motor but Siemens

vitesse · 6th June 2019, 10:23

Nice hot day at 28c, shortly after start heard a noise from the front and knew somehow that it was the fan blades parting company. The fan was replaced before I bought the car last December.

Surprised indeed by what I found when I removed the bumper, blades marked Siemens, peeled back the unusual white sticker which just reveals a round hole.

Any idea of how to permanently reattach it to the spindle, I doubt if it could be drilled and threaded. I do have a dead commutator damaged fan with the correct mounting on the spindle, but has anyone tried to remove the mounting, succeeded?

Regards

T-Cut · 6th June 2019, 10:53

It looks similar to an MGR fan motor, but it's not. The field windings of the original motors are not exposed as shown here and it has has a mounting flange permanently attached to the spindle. This fan unit would seem to have a different blades attachment system, though it's unclear what. The OEM fan unit is attached to the flange by three 'bayonet' clips in the central boss area. There appears to be nothing like that here. It surely can't be a simple push fit into the spindle?

Can you post a closeup photo of the rear fan centre?

EDIT:
Here's a photo that shows a side view of the flange.

TC

vitesse · 6th June 2019, 12:03

Thanks for the reply, strangely it resembles the original but isn't and the blades are just a snug push fit on the spindle. No locking mechanism.

Sorry, no picture of the rear at the moment as it's still mounted.

I tried to remove the old three bayonet clips (as many have tried) using heat first but only managed to break one of the clips.

Regards

T-Cut · 6th June 2019, 14:46

Was it performing satisfactorily before the fan came off? Looking at the size of the spindle, I'm a bit sceptical it has anything like the power/displacement rate of an OEM system. Is the fan the same size and shape as usual? Is there any indication of power/wattage on the motor?

As to refitting the blades, I fear once this push-on type fitting has separated, it will continue to separate. I guess you could try bonding it on with a film of superglue. The problem is, it's an interference fit, so no place for an adhesive to go.

TC

vitesse · 6th June 2019, 18:08

Yes, it worked well at least in the six months I’ve had the car, the running temperature is a constant low 90s and the AC in continual use. I tested the fan several times when I bought the car as the car was seriously overheating (airlock) https://the75andztclub.co.uk/forum/s....php?p=2690481

Superglue is exactly what I’ve used as a temporary measure until I can get a replacement.

Fan looks like the original and the mountings are identical but I’ve not seen any marking on the casing, the spindle diameter doesn’t seem all that different either but now the superglue is in place I can’t measure it. Perhaps later when the replacement arrives, if I get the glued blades off!

I might ask the supplying garage where they got the fan unless someone comes along and identifies the fan motor, otherwise it might remain a mystery, thanks for your input.

Regards

T-Cut · 7th June 2019, 08:10

It seems that Siemens have simplified the fan attachment. A pressed-on fit using a metal ferrule (I think from your photo) makes it simpler/cheaper, functional but not replaceable. So, you have to buy a new fan/motor assembly rather than just the fan unit. It's logical I guess since 99% of the problems are with the motor.

In that context, I notice the low speed resistor is the original 50-75 watt type. You should consider upgrading that to the recommended 'Gold' 100 watt version. The one you have will fail sooner or later. You can get one from electronics outlets like Farnell, from forum traders and from eBay.

TC

6th June 2019, 10:23	#1
vitesse I really should get out more....... Rover 75 Saloon Join Date: Jul 2011 Location: Gävle Posts: 2,537 Thanks: 395 Thanked 823 Times in 652 Posts	Strange fan motor but Siemens Nice hot day at 28c, shortly after start heard a noise from the front and knew somehow that it was the fan blades parting company. The fan was replaced before I bought the car last December. Surprised indeed by what I found when I removed the bumper, blades marked Siemens, peeled back the unusual white sticker which just reveals a round hole. Any idea of how to permanently reattach it to the spindle, I doubt if it could be drilled and threaded. I do have a dead commutator damaged fan with the correct mounting on the spindle, but has anyone tried to remove the mounting, succeeded? Regards Last edited by vitesse; 7th June 2019 at 09:14.. Reason: spelling

6th June 2019, 10:53	#2
T-Cut This is my second home Rover75 and Mreg Corsa. Join Date: Nov 2006 Location: Sumweer onat mote o'dust (Sagin) Posts: 21,753 Thanks: 341 Thanked 3,660 Times in 2,924 Posts	It looks similar to an MGR fan motor, but it's not. The field windings of the original motors are not exposed as shown here and it has has a mounting flange permanently attached to the spindle. This fan unit would seem to have a different blades attachment system, though it's unclear what. The OEM fan unit is attached to the flange by three 'bayonet' clips in the central boss area. There appears to be nothing like that here. It surely can't be a simple push fit into the spindle? Can you post a closeup photo of the rear fan centre? EDIT: Here's a photo that shows a side view of the flange. TC Last edited by T-Cut; 6th June 2019 at 11:49..

6th June 2019, 12:03	#3
vitesse I really should get out more....... Rover 75 Saloon Join Date: Jul 2011 Location: Gävle Posts: 2,537 Thanks: 395 Thanked 823 Times in 652 Posts	Thanks for the reply, strangely it resembles the original but isn't and the blades are just a snug push fit on the spindle. No locking mechanism. Sorry, no picture of the rear at the moment as it's still mounted. I tried to remove the old three bayonet clips (as many have tried) using heat first but only managed to break one of the clips. Regards

6th June 2019, 14:46	#4
T-Cut This is my second home Rover75 and Mreg Corsa. Join Date: Nov 2006 Location: Sumweer onat mote o'dust (Sagin) Posts: 21,753 Thanks: 341 Thanked 3,660 Times in 2,924 Posts	Was it performing satisfactorily before the fan came off? Looking at the size of the spindle, I'm a bit sceptical it has anything like the power/displacement rate of an OEM system. Is the fan the same size and shape as usual? Is there any indication of power/wattage on the motor? As to refitting the blades, I fear once this push-on type fitting has separated, it will continue to separate. I guess you could try bonding it on with a film of superglue. The problem is, it's an interference fit, so no place for an adhesive to go. TC

6th June 2019, 18:08	#5
vitesse I really should get out more....... Rover 75 Saloon Join Date: Jul 2011 Location: Gävle Posts: 2,537 Thanks: 395 Thanked 823 Times in 652 Posts	Yes, it worked well at least in the six months I’ve had the car, the running temperature is a constant low 90s and the AC in continual use. I tested the fan several times when I bought the car as the car was seriously overheating (airlock) https://the75andztclub.co.uk/forum/s....php?p=2690481 Superglue is exactly what I’ve used as a temporary measure until I can get a replacement. Fan looks like the original and the mountings are identical but I’ve not seen any marking on the casing, the spindle diameter doesn’t seem all that different either but now the superglue is in place I can’t measure it. Perhaps later when the replacement arrives, if I get the glued blades off! I might ask the supplying garage where they got the fan unless someone comes along and identifies the fan motor, otherwise it might remain a mystery, thanks for your input. Regards

7th June 2019, 08:10	#6
T-Cut This is my second home Rover75 and Mreg Corsa. Join Date: Nov 2006 Location: Sumweer onat mote o'dust (Sagin) Posts: 21,753 Thanks: 341 Thanked 3,660 Times in 2,924 Posts	It seems that Siemens have simplified the fan attachment. A pressed-on fit using a metal ferrule (I think from your photo) makes it simpler/cheaper, functional but not replaceable. So, you have to buy a new fan/motor assembly rather than just the fan unit. It's logical I guess since 99% of the problems are with the motor. In that context, I notice the low speed resistor is the original 50-75 watt type. You should consider upgrading that to the recommended 'Gold' 100 watt version. The one you have will fail sooner or later. You can get one from electronics outlets like Farnell, from forum traders and from eBay. TC