75 Saloon Parcel Shelf Removal (with rear blind)

[Matt_75]

Originally Posted by macafee2

I hope my memory is not playing tricks on me with this post but I seem to recall, be careful taking the gearbox apart. There is a coiled spring in there. When I took the cover off the spring uncoiled.

macafee2

Thanks for the heads-up, unfortunately for me, I read it a bit too late. I discovered the spring loaded mechanism the hard way! I think I found all the pieces.

[stocktake]

Originally Posted by Matt_75

Thanks for the heads-up, unfortunately for me, I read it a bit too late. I discovered the spring loaded mechanism the hard way! I think I found all the pieces.

[Matt_75]

Here's the stripped down and cleaned mechanism:



I hope this is everything after the disassembly explosion! There are six screws missing from this picture that are in a separate tray.

It'll get a final check over and before being reassembled. Looking down on the gear mechanism, it rotates anti-clockwise when raising the blind, so it's important that the spring is correctly tensioned to assist this.

[macafee2]

Originally Posted by Matt_75

Thanks for the heads-up, unfortunately for me, I read it a bit too late. I discovered the spring loaded mechanism the hard way! I think I found all the pieces.

Sorry

macafee2

[macafee2]

Originally Posted by Matt_75

Here's the stripped down and cleaned mechanism:



I hope this is everything after the disassembly explosion! There are six screws missing from this picture that are in a separate tray.

It'll get a final check over and before being reassembled. Looking down on the gear mechanism, it rotates anti-clockwise when raising the blind, so it's important that the spring is correctly tensioned to assist this.

If you get it reassembled and it works, please let me know, as I think I have one that I took apart and it "exploded". I'd like to know how you did it.

macafee2

[Matt_75]

I decided to do a dry reassembly run before greasing it all up. Here is how I put it back together.

1. Attach the spring to the large diameter wheel, ensuring the outer tang locates properly in the groove as shown at the top of this photo.



2. The inner tang now needs to locate in this slot near the brass bushing in the main body. This is a bit fiddly and I used a pick tool to help locate it.





3. Insert the torx screw that acts as a stop for the mechanism to prevent over-rotation. In hindsight, this could be done first.



4. Locate the shaft of the smaller diameter wheel in the corresponding blind hole.



5. Put the brown coloured smaller diameter wheel onto the shaft ensuring it meshes with the large diameter wheel properly.



6. Now it's time to tension the spring, which is a bit tricky. Rotate the brown wheel anti-clockwise, which in turn will rotate the large wheel clockwise, until it hits the stop screw. Holding it in place, insert the motor and mesh the worm gear to keep everything still. Make sure the worm gear stays meshed as the brown wheel has a tendency to want to lean away from it which could cause it to disengage and unwind the spring.



7. Insert the screws into the motor ensuring the spring/gear assembly doesn't move.



8. Put the top plate on. I used a thin trim tool to push the shaft of the brown wheel to get it to locate properly in the brass bushing of the top plate. Insert the top plate screws.



That's it. I did a quick bench test with a 12v battery and it seemed to work properly. I've now disassembled it ready for final assembly with grease.

[Arctic]

Hi Matt.
Big thank you from & lots of other members i would think, nice clear neat how to.

What grease are you going to use, normal clear grey grease, or the gold grease.

[Matt_75]

Originally Posted by Arctic

Hi Matt.
Big thank you from & lots of other members i would think, nice clear neat how to.

What grease are you going to use, normal clear grey grease, or the gold grease.

No problem . Thinking about the assembly procedure, it might be possible to put it together without doing the fiddly spring tensioning bit, provided the first thing you do after it's built is run the motor in reverse (lower the blind). I would want to test that theory before committing to it though.

I'd appreciate a bit of advice on the grease actually. I don't know what the original yellow coloured grease was. Does anyone on here know?



I've seen posts from another member saying he used multipurpose lithium grease so I was planning to do the same.

[SD1too]

Originally Posted by Arctic

Hi Matt.
Big thank you from & lots of other members i would think, nice clear neat how to.

Yes, an excellent account with clear photographs, thank you Matt. I hope that the moderators will preserve this in the "How to" section so that it's available for easy reference.

Simon

[Matt_75]

There's something else I want to test too. I've been thinking about why the stop screw is a separate piece and why it wasn't integrated into the housing.

When I tensioned the spring, I rotated the large wheel through about 90 degrees before it hit the stop. I'm wondering if this should be done without the stop screw in situ and whether the spring should be tensioned through 450 degrees of rotation (360, insert stop screw, then 90).

When the assembly "exploded" it seemed to be under a lot of tension but it's hard to say as I didn't get a good look. When I did the dry assembly, there didn't seem to be as much.