Roof motor sticking
- Thread starter Dadzilla
- Start date
Attleborough, Norfolk
@Dadzilla - is it possible for you to post more photos of the motor as it is now?
I can only assume there has been a miscommunication somewhere.
I would hope you can see that if the reservoir were inverted then fluid would sit in the top/bottom (end with the filler plug) and not cover any of the intakes to the pump itself.
When the motor is installed in it's designed position, behind the left roof hinge, it sits more or less upright, with a slight tilt to the rear. The reservoir is most definitely on the top. In fact I have just tried fitting a motor upside down in the original casing and it won't fit, due to the taper of the case and the bulk of the pump unit.
When the motor is relocated to the boot, it is typically fitted at more of an angle. This can mean that what was sufficient fluid in it's original position is now not quite enough to prevent air getting sucked in during operation. This is why, when we move the motors, we stand them upright and add more fluid to the reservoir.
I can only assume there has been a miscommunication somewhere.
I would hope you can see that if the reservoir were inverted then fluid would sit in the top/bottom (end with the filler plug) and not cover any of the intakes to the pump itself.
When the motor is installed in it's designed position, behind the left roof hinge, it sits more or less upright, with a slight tilt to the rear. The reservoir is most definitely on the top. In fact I have just tried fitting a motor upside down in the original casing and it won't fit, due to the taper of the case and the bulk of the pump unit.
When the motor is relocated to the boot, it is typically fitted at more of an angle. This can mean that what was sufficient fluid in it's original position is now not quite enough to prevent air getting sucked in during operation. This is why, when we move the motors, we stand them upright and add more fluid to the reservoir.
Yorkshire
I appreciated all the advice and offers of assistance, so thank you to everyone who responded to the post. I'm new to the Z4, so i'm just a newbie, learning the ropes and the advice was appreciated. The relocation into the boot had been done by the person I bought the car from, so I suspect that it was just a case of lacking sufficient knowledge. Living in rural North Yorkshire, it's not always easy to find people with practical knowledge of the Z4. Logically though, fixing the problem so easily by inverting the roof motor does lead to a conclusion that he was right. As for cost, I don't think he charged much for that specific change as the car went in for other work and it took him all of 15 minutes to cut the zip tie, invert it, and test it.
I'm very sorry to sound so doubtful, but any chance of a photo or two?
Basic physics dictates that the pump should not operate upsidedown.
OP take this in the spirit it’s intended
When you put a post up asking for help you’ll get decent, experienced input from the forum. It’s not Facebook. But people want to help and share experiences to assist you sorting your issues and take time to reply.
If you choose to do something else that contradicts that it’s totally up to you. No skin off our nose etc.
Sadly the responses IF the roof doesn’t work in future may not be as forthcoming. You’ve got several people telling you from experience that the motors and pumps don’t work when inverted. An interesting point raised by another EXPERIENCED forum member is that AI thinks that the correct position for the pump reservoir is down.
AI is wrong.
As per my previous post- a little knowledge is a dangerous thing
When you put a post up asking for help you’ll get decent, experienced input from the forum. It’s not Facebook. But people want to help and share experiences to assist you sorting your issues and take time to reply.
If you choose to do something else that contradicts that it’s totally up to you. No skin off our nose etc.
Sadly the responses IF the roof doesn’t work in future may not be as forthcoming. You’ve got several people telling you from experience that the motors and pumps don’t work when inverted. An interesting point raised by another EXPERIENCED forum member is that AI thinks that the correct position for the pump reservoir is down.
AI is wrong.
As per my previous post- a little knowledge is a dangerous thing
I fully concur.
Will I be so quick to lend support and advice next time around? That's up for debate at the moment I'm afraid.
As I did try to explain before, I appreciated the feedback and followed what I could from the advice. It was indeed helpful. It wasn't AI that informed me, it was the first reaction of the BMW specialist when he saw the motor mounted in the boot. Had I been younger and more agile, I would have willingly grabbed my tools and explored the possibilities and fixed it myself, but sadly at 70, I'm less agile at scrambling around in the boot. Strangely the Z4 is easier to get into than my 1 series as the sill is lower and thus easier to get my leg into. Actually, I tried to DM some members who responded, but seems DMs are not permitted. The takeaway from the helpful messages is that I learned a lot about the roof motor and how it generally functions, so those posts were not wasted effort by any means. Once again, thank you to all who responded.
Could we see a photo of its new installation please. Purely out of interest and to further my education. Thank you
Oh and btw, once you get to 5 posts you can DM, so should be able to now.
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Please??