does anyone know how to disassemble? I looked on youtube &google, no real help.

thanks

Some years ago there were several books authored by JB Wood on
firearms assembly/disassembly and one covered .22 rimfire rifles. The
Ithaca 66 was one of the rifles included in the book. The books were
Gun Digest publications and you might be able to search online and
find the info on the Ithaca 66. I have a copy of the book on .22 rifles
around here somewhere and I'll try to find it if you can't find anything
online.

The IthacaM-66 is a single shot shotgun. They look a lot like a rifle because they have an lever like a rifle that breaks the barrel.

My first gun was a M-66, "Super-Single" in 20 gauge.

I have no idea how to disassemble one however. Sorry.

They made a similar looking 22 that was a lever action, falling block called the Model 49.

__________________
John 3:16 .

Take the butt plate off. Under it is the stock screw. Unscrew that and the action with the approx 6" long mainspring tube attached will simply pull forward off the stock.

Inside that mainspring tube is the coil mainspring and it's follower pushing against the hammer. That is giving the spring tension to the hammer now.
To relieve that spring tension, just unscrew that mainspring tube from the back of the frame.
As you do the tension is reduced and as the tube with it's spring comes right off,,the follower can be taken out the back end of the frame too.
The follower is just held in tension betw the spring and the hammer.

Now you have the mainspring out.
You can now punch out the cross pins from the frame that hold the hammer,,trigger,,and lever in place.
Punch them out from left to right as assembly was most likely from right to left.

The frame is an alloy so go easy on the thing holding it in a padded vise.

When you drop the lever out of the frame, that will allow the locking bolt to be removed out the front of the frame.
The rounded hump on the top portion of the pivot point of the lever cranks the bolt back and forth by engaging the slot cut on the bolt.

There's a small coil spring & plunger in the back of the bolt to give it power,,watch for that so you don't loose it.
That plunger and spring is also the trigger spring.

Also in the top of the pivot surface of the lever after you drop it down and out there is another small plunger and coil spring behind it to give the lever a snap into position hold in the closed and open positions.
Neither of these plunger/spring assemblys are secured in their mother assemblys with a cross pin or staking,,just placed in them and then assembled.
So they can fall and crawl away if you don't notice them in dissassembly and then wonder why the lever flops open and the bolt won't stay closed when you reassemble your prize.

The hinge pin in the front of the frame is removeable. The hinge pin itself has no threads on it IIRC but the head is slotted. The opposing side is a screw that threads into the end of the pin and holds the pin in the frame.
Put a screw driver in each side and turn,,one will unscrew, then push the hinge pin out of the frame.
Some may have a lock slot on the head of the hinge pin to engage the frame,,so you'll know which is the pin itself. But still use a screwdriver on that side to take the torque in assembly/removal so you don't twist the alloy stud off if it resists.

The firing pin is a simple single piece held by a short cross pin in the frame. A small coil spring in there for a retractor.
Punch the cross pin out and the pin and spring come out the back.

There's the ejector in the bbl,,there's 2 different styles. Early and late.
I can never remember which is which.
One has a round stem,,the other a flat or keyed stem on the shaft that slides in the hole under the chamber.
I think the round one is the later style,,easier to make.
Pins, springs and an ejector cam on the side of the bbl assembly to trip the ejector as the bbl is opened.


That's about all I can remember. Might be a few flaws in my recollection but it's probably complete enough for you to get it apart and not get in trouble.
They are simple and that removal of the mainspring by unscrewing it from the frame makes things a lot easier than wrestling with one up inside the frame.
Reassemble in reverse order...
Hope this helps

this helps tremendously! thanks 2152hq

Oops, I haven't seen my reference books for a while and I got the 66
and 49 mixed up. A senior moment.