This lens was in bad shape … though I expected that based on the sellers images.
It needed a body cleaning, and also the built in metal lens hood has a dent. The previous owner did not try to fix the dent so continued to retract it as seen by the scrapped of black paint on the inside.
… those things are doable … the fungus, well that will be this story.
I searched the web and it appears nobody has posted an attempt to take this lens apart … not being sure if I could get inside the element groups (sometimes they are encased) I took a chance on purchasing this lens.
You will need a wide spanner wrench as the front element is huge.
First I needed to get the built in hood off. First pull off the rubber ring. Remove the black tape. Then finally pull off the black metal top ring.
Now you can slide the hood off … in my case some bending had to start first.
You can use a filter ring vise, wood dowels and a hammer, etc … to put the hood back into shape.
The front lens label ring is notched to allow a spanning tool to unscrew the entire front lens group … there are four large elements in this.
Be nice, and don’t slip … this group is very secure.
Once unscrewed. When you hear it pop out of the last thread, cup the end and turn the lens over … it should just fall out.
You can split the top group in half to get into it.
There is more tape … remove it, then you can unscrew the top part.
The rear section has some “lock tight” type substance to keep it from unscrewing … I did not have to go there.
Clean up the elements.
Under that front group you can get to the
If you open the aperture you can get at the front of the internal element group to clean it up.
Now to clean your backside … sorry the back of the lens.
Take out those four screws.
The pull off the mounting ring.
I missed taking a picture of the cap … remove the screws that hold that on.
Pull it off, while watching out for the wires.
At the bottom of the wires there is the distance switch set. Take the two screws off that hold it.
Take one end of the spring off the hook.
Remove the four screws that hold the collar on. Remove the collar.
Remove the screws that hold the rear element ring on.
Pull off.
Now you can use the spanner to unscrew the rear element group.
You can clean the rear of the internal group.
There, that wasn’t all that difficult eh?
Now put it back together … make sure the aperture lever and focus moves before tightening each part.
Tip: as I suspect the lens hood is the last part you will put on … the top lip should be tight enough so that when the hood is retracted it has contact enough to keep the hood from easily falling forward when you tilt the lens downward. I did a little light bending before I put the black metal ring on.
I was lucky that the fungus was only on the surface of the coatings, so it cleaned off easily. Not much I can do about the body paint … it ain’t white, but I was able to scrape off the green brass erosion on the nameplate.