EF 400mm f/5.6L USM - Focus Ring no longer responds. Cost to service/alternatives?

[quadceratops]

Howdy folks!

I've got a 400mm f/5.6L lens that I've let a friend borrow.  I purchased the lens used myself and it's now pushing 10 years old.  

My friend reports that the Focus Ring does not respond when the lens is in Manual Focus mode, but there is still a thin part of the ring that does respond. To quote his words, "on the end of the ring, there's a tiny thin part that adjusts the focus but it seems like it got disconnected from the main grippy part."  It seems to me that there must be a mechanism internally that connects the rubber focus ring to the part that actually focuses, but that connection must've died somehow. 

Autofocus seems to work fine, but without MF it seems like a real problem for resale at any level.

Has anyone had a repair like this completed on their lens?  A quick call to my local retailer stated that weather-sealed lenses need to be "broken" to be rebuilt, which means this could be easily a $400+ repair, which to me is about what I was hoping to sell the thing for.  In other words, it would be "totaled" and I wouldn't pay for that repair.  Does that seem accurate?  

Is there anything else you can do to salvage this lens for manual focus?  I read a similar post that suggest maybe even just taping the ring to the part that still works... but I'm guessing that would be a last resort option.

Thanks for any help!  Cheers!

[ebiggs1]

I have had two of these lenses and they are fantastic lenses.

The ring of metal barrel between the focus distance window and the rubber grip is slipping you can use gaffers tape to attach it to the focus grip ring. However, a new rubber grip should be the long term solution. I think Canon used double sided tape but it may have been glued.  I can't remember. I doubt Canon still services that lens but a call yo Canon will clear that up.

"...call to my local retailer stated that weather-sealed lenses need to be "broken" to be rebuilt, ..."

That's BS. In the first place the ef 400mm f5.6L is not a totally weather sealed lens. It has some weather sealing around the switches and that's it. It also requires a front element filter for weather sealing. BTW, keep in mind weather sealing or resistance does not mean it is waterproof or even weatherproof. Totally different terms.

[shadowsports]

@Ernies advice is spot on.  

@quadceratops,

Don't be the guy that runs around with tape on his lens.  Get the lens repaired if its not cost prohibitive and is still serviceable.

Register the lens in your MyCanon Acct.  Initiate a repair request.  You'll be given a quote with shipping instructions.  At that point, you'll be better position to make an informed choice.  

MyCanon

1-800-652-2666

[wq9nsc]

I agree with Ernie that this is a fantastic lens and I shot a lot of soccer with it before moving up to an EF 400 f2.8.

As Ernie noted, it is possible that the rubber ring is slipping but I think it is also possible that your friend is used to zoom type lenses and is trying to use the rubber ring on the integrated lens hood instead of the proper pair of rings on the main barrel which are just two different diameter grips on the same barrel and are mechanically interconnected by being mounted to the barrel.

Rodger

[quadceratops]

Thank you @ebiggs1, @shadowsports, @wq9nsc for the feedback.  As I began to fill out the Canon Support form, it showed me the $400 price tag, which is what I was afraid of.  Is there any chance that it's ever less than that, or is that basically the cost to open up the lens?

[deebatman316]

The quote will change when Canon has the lens. They need to verify the problem and see what parts are needed for the repair. Then how much time it will take for the repair. Without the tech having the lens they don’t know what’s exactly broken.