my dis rotor not spinning 1970s 350

after going threw everything to figure out why i have no spark i just found out today when cranking the motor over the top rotor not spinning  i dont know why yet... i have a 350 stroked to 383 twin 650 holly carbs high rize intake   and i have to take that all off to get the dis out of the intake to look at it ...  is it worth my time?  the motor still has comp when its cranking over so i dont think the timing chain broke or cam snapped .. How likly is that? i just got the car 2 days ago and havent heard it run yet to hopfully it just has a broken dis gear?      but... the dis is all the way in and you try to turn it by hand... you cant but undo the bolt and pull it out a little bit you can    someone please help me out with this!!! im new to this site  please respond to race4lf19@yahoo.com  and or on here to .. Thanks So much if you guys can help me out!!!!

ps the dipstick on right side  

i say pull the distributor and see if the gear is worn, eaten, or if the roll pin that holds it on has snapped...letting the gear spin on the dist. shaft
hopefully it's one of these

if the gear looks good, look down into the dist. hole with a flashlight to see if the dist. drive gear on the cam is good

good luck  
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i did love my chevette (first car) more than my first wife
my 94 4.3L Astrobrick would outrun the 99 5.4L f350 i had to drive for work

there are several things that might have happened...

you may have a locked up  oil pump...   when the oil pump locks up.. the pin that locks the distributer gear to the shaft shears... they do call it a shear pin....    

the oil pump is driven off the distributer shaft...  so when the pump locks up the shaft stops spinning.. the engine dies and you still have compression...

i really don't think you have to pull the intake manifold off to get the distributer out..    i would worry about any left over shear pin pieces... that have dropped into the oil pan...    you might really want to pull the distributer...  hopefully.. the gear will come up with it ... and the outer pieces of the roll pin may still be locked into the gear...

plan on buying a magnet on an antenna type of tool to search around for any more if you cannot find all of them...

you can get a oil pump priming tool from autozone or other tool stores... and spin the oil pump with a drill to see if it still works...    all this can be done from the top....

if you have not enough room to get the distributer out.. i wonder how they got it in...

this might just cost a buck or two to get a replacement roll pin from the local ace hardware..

depending on your oil drain plug location.. you might want to drain the oil into a totally clean pan..    then fish around inside the bottom of the pan with the magnet on the antenna.. to see if you can pick up any more pieces of pin...

this is one of the best reasons to put big strong magnets in the corners of the oil pan.. on the inside..  

Defintiely pull the distributor. If the gear has no abnormal wear, then make sure the roll pin securing it hasn't sheared off, as mentioned above.  

one thing... while you are inspecting the roll pin.. it is important to drive it out...  and inspect the whole length..

i have found them intact on the ends... but totally sheared in the middle out of site.. only driving them out will tell for sure...