DIY repair of Canon EFS 18-133mm lens

[callistix]

Hi everyone,

First of all sorry for posting this in the section for analog workflow, but I couldn't find any suitable section elsewhere.
Please feel free to move the thread if needed.

I own a Canon EOS 7D with a Canon EFS 18-133mm lens which just started to fail.

The lens was already in repair with Canon and although they claimed to have it fixed, it started to have a problem with autofocus, I have the impression that it's never 100% in focus, and when the autofocus drives the lens, it does some slight horizontal movement which is odd and did not happen before.

Now since today, when shooting with enabled AF, the motor does not move at all, and after the image was taken this error appears on the screen:

Needless to say that it's not the contacts, but I've cleaned them anyways just to make sure.

The repair warranty is now over and I will try to fix it myself.
Please do not respond and suggest to have it fixed by a professional. I am not going to do that.

So, first things first: When shaking the lens I heard some rattling and it seemed that a part came off.
So I checked some disassembly videos like these:



I opened the lens and found the loose parts:

It's not apparent to me where this screw belongs to, but I guess it has something to do with autofocus.
The screw is apparently made to fit inside the copper case and hold it in place somewhere.
I was looking for a part catalogue for the lens but I could not find anything.

I got stuck at some point when disassembling without finding anything where this part could belong to.
I couldn't go past this point, as the disassembly videos don't give enough information and it's not apparent how to continue:

I would be super thankful if anyone has an idea where this part belongs to, and how to refit it.
It would also help me if anyone would just guide me with the next steps for disassembling the lens.

Thanks and greetings,
vitaminx

 

[shutterfinger]

Images do not show.

 

[callistix]

Images do not show.

Seems to be some weird issue with JPG encoding, fixed that now by linking to .png images.

 

[shutterfinger]

Where was the screw and bushing when you opened that wiring nightmare?

 

[RalphLambrecht]

Hi everyone,

First of all sorry for posting this in the section for analog workflow, but I couldn't find any suitable section elsewhere.
Please feel free to move the thread if needed.

I own a Canon EOS 7D with a Canon EFS 18-133mm lens which just started to fail.

The lens was already in repair with Canon and although they claimed to have it fixed, it started to have a problem with autofocus, I have the impression that it's never 100% in focus, and when the autofocus drives the lens, it does some slight horizontal movement which is odd and did not happen before.

Now since today, when shooting with enabled AF, the motor does not move at all, and after the image was taken this error appears on the screen:

Needless to say that it's not the contacts, but I've cleaned them anyways just to make sure.

The repair warranty is now over and I will try to fix it myself.
Please do not respond and suggest to have it fixed by a professional. I am not going to do that.

So, first things first: When shaking the lens I heard some rattling and it seemed that a part came off.
So I checked some disassembly videos like these:



I opened the lens and found the loose parts:

It's not apparent to me where this screw belongs to, but I guess it has something to do with autofocus.
The screw is apparently made to fit inside the copper case and hold it in place somewhere.
I was looking for a part catalogue for the lens but I could not find anything.

I got stuck at some point when disassembling without finding anything where this part could belong to.
I couldn't go past this point, as the disassembly videos don't give enough information and it's not apparent how to continue:

I would be super thankful if anyone has an idea where this part belongs to, and how to refit it.
It would also help me if anyone would just guide me with the next steps for disassembling the lens.

Thanks and greetings,
vitaminx

if you are not having it fixed by a professional, you've got a screw lose.

 

[callistix]

Where was the screw and bushing when you opened that wiring nightmare?

It came out after removing the top cover, but I think it was located more in the interior before.

if you are not having it fixed by a professional, you've got a screw lose.

Yes, literally

Oh, and it would also be helpful if somebody could tell me where to get a parts catalogue, an exploded view drawing, or maintenance instructions from.

Thanks!

*EDIT*
This is the part: eBay

 

[shutterfinger]

Oh, and it would also be helpful if somebody could tell me where to get a parts catalogue, an exploded view drawing, or maintenance instructions from.

Likely a Canon authorized service center only. Nothing comes up in a google search other than some youtube videos. Search term: Canon EFS 18-133mm lens repair manual or Canon EFS 18-133mm lens service manual.

 

[AgX]

In the first video that scew and bushing are visible. Exactly were to expect them: as helicoid guide.
However in your photo they appear different, what puzzled me until watching that video...

 

[callistix]

In the first video that scew and bushing are visible. Exactly were to expect them: as helicoid guide. However in your photo they appear different, what puzzled me until watching that video...

You mean at 12:49? Seems you're right, I didn't notice that before!
I didn't pay a lot of attention at the last part of the video because I got stuck at 12:13, where an important step is left out.

But good to know already where they are located, just have to find out how to separate the outer from the inner focus tube.

 

[AgX]

That being a roller guide was my first idea, though the ones I knew were from plastic,and in your own photo they look like from plastic too. But in that video one clearly can see a brass shine from such roller/bushing.