Crank won't turn

Well long story short, on my '76 900ltd I pulled my head to have some work done and decided to pull jugs to have them cleaned and painted. Well I went to put jugs back on and found that the crank will only turn 45degrees, for that distance it turns freely then stops with a clunk that sounds like its coming from the rotor side. Well I'm at a loss so any ideas welcome...I really don't want to split the case:(

might cost you some gaskets but you could pull the alt.cover and make sure that there is not anything (screw)in there getting jammed up in there.it is possible to see almost all of the crank by pulling the ign and alt covers and dropping the pan.i would start by pulling the alternator cover,if you are careful you might be able to reuse the gasket with a lite dressing of sealer.my02fwiw

Well I guess I won't have to buy a new oil drain plug.... I let my friend and his 4 year old boy hang out an "help" for a bit and guess what I found. Yup the magnetic oil drain plug wedged under the crank. Gotta have the 4 year old keep a better eye on my Buddy stop him from putting cool things in places they shouldn't

So did it do any damage?
Did you get the crank to turn over completely?

Wow...whoda thunk it,eh...a magnetic drain-plug?

I'm assuming it WAS the magnetic piece that came apart,and stuck to the crank?:ohmy:

Nope someone dropped the whole plug in and it was stuck to bottom of the crank under #1. I tried turning it by hand and never forced it so there was no damage. Stangest thing I've ever found in a crankcase.

The WHOLE PLUG?!!:ohmy:

How in the HELL?:blink: ...awww,nevermind,lol.
Some people should really just stick to sewing-machines!