Engine Won't Turn
 

65 convertible 289/c4. I recently installed my engine and trans. I can turn the engine freely by hand but after I installed the starter it will only turn so far and then stop. When I remove the stater it turns freely again all the way around. I know I have the correct starter and I am 80% sure I installed the torque converter properly by lining up the drain plug with the hole in the flex-plate. Is this normal for the engine not to be able to turn 360 degrees when the starter is installed? I am afraid to try and turnover the engine until I have this sorted out.

Something is wrong there. I'm not sure I understand what drain plug you are referring to. The starter shouldn't make contact with flywheel until actual starting of engine so something is out of alignment.

Not normal, either your ring gear is not round or the converter is the issue.

Or you need to shim the starter.

Thanks for the quick replies. The torque converter has a small drain plug on the back that you are suppose to line up with a hole in the flex-plate. Do the starters normally need shims when installed?

i think it will vary engine to engine.
remove the starter and the cover plate on the lower part of the bell housing to see into the flex plate and torque conv. have someone turn the engine for you by hand while you observe the flexplate from underneath. make sure it is turning uniformly. also check the drain plug you are concerned about. make sure all your torque conv bolts are in and tightened all the way. also check to see if the bellhousing is is tight to the engine block. if not, that will skew things too. like someone else said the starter should not be engaged to the flexplate gear until you turn the key to start the car. if everything is tight, etc., maybe your flexplate is warped. keep us posted.

thanks woodvette that worked. it was the drain plug causing the flexplate not to turn uniformly. do you think the flexplate is now permanently warped or when I properly bolt the torque converter to the flexplate will it go back to its original shape?

not sure. depends on how warped it was. you can try bolting it up properly now and going looking at the flexplate again while someone is turning the engine over for you by hand. look and see if it turns true. i am not sure of any tolerance for an out of true flexplate. good luck.

you can put a dial indicator on the flexplate and turn engine by hand with comverter connected and see. if it is more than around .025" out, i would replace it.

Same issue my fix
 

I had the same issues.

1. My issue was that I had a 289 and a c4 tranny I replaced the engine with a 1980 302. when I bought my starter I bought a 289 starter. It would grab for a second then just spin. There is such a small difference I couldn't tell when I took it back and got a 302 1980 starter till we measured the shafts.

2. If you didn't install the mid engine plate you will have to shim the starter. Totally recommend installing the mid engine plate you will have issues with that starter down the road.

3. Another issue is that the counter weight is hitting your starter because you have the wrong mid engine plate or not one at all and or starter. Take the little assess plate off and have someone turn the engine while you watch the flexplate turn. watch and see if it gets hung up in the same spot every time mark a reference point to see.

4. last one is that the mid engine plates differ year to year some are not straight and they have humps in them. If you went from a 50oz to 28oz flexplate they will hit the humps. Look at the flexplate for rubbing. 289 mid engine plate should be flat. Something I learned the mid engine plate serves the purpose of shimming the starter and distributes the torque of the tranny and engine evenly on the bellhousing.

took almost 3 weeks to figure all this out had everyone of these issues at once but kept fixing one at a time LMAO!