Chrysler Repair: 2.5 V-6: interference or non-interference?, interference engine, tensioner pulley

Question
I have just changed the timing belt and water pump on my bosses car. It has a 2.5L V6 Engine. After aligning all timing marks to TDC. My helper moved the crankshaft without the timing belt on. I reset the #1 CYLINDER to TDC. I further consulted with to different aftermarket manuals (Chilton and Haynes)one said to back the crankshaft off 3 degree after reaching TDC the other just said to set both camshafts and crankshaft to TDC marks. I followed this rule as this manual had more detailed instructions. This manual further stated after replacing the tensioner pulley (and torquing to 39 ft pounds) the holding pin should side in and of the set hole with ease(this did not happen). After completing all other work we went to start the car we immediately and heard a loud screeching noise and stopped. I immediately checked the crankshaft and tried to turn the engine by hand. The engine will only turn a quarter turn either way and then locks. I am thinking this could be a bent valve but this is supposed to be a non-interference engine. Any suggestions Boss is due back Wednesday.  

Answer
Hi Mike,
I have to admit that if it is non-interference the manuals don't specifically say so. The Chrysler fsm's say that the pistons have cut outs for the valves, but don't mention the interference issue at all. On the other hand the Haynes says to not turn the crank when the belt is off, and also that damage may have happened if the belt broke while the engine was in motion and that you shouldn't rotate the crank without the belt being in place, which sure sounds like interference to me.  So I would conclude it is an interference design. What was the history before you opened it up?
So I would only turn the crank with the belt in place and the timing marks pretty well aligned.
On the locking up you experience now, about the only other possibility is that the starter motor sprocket/flex plate meshing is disturbed such that the bendix is not retracted but rather holding the sprocket in mesh with the flex plate and one or the other is damaged. So you might try taking off the starter motor to see if that frees up the crank rotation.
On the timing belt install, the Haynes appears to follow the fsm accurately. Do you have that special adapter Miller Tool 998767 to do the torqueing? Read that procedure carefully and follow it to the letter. If the pin still won't pull easily, the measure the extension of the tensioner rod as installed to see if it is withing the range of 3.8-4.5mm in which case it is acceptably set.
Roland