Need help BMW 745 engine locked

Hi everyone am new to this forum
And this is my first Bmw my BMW was leaking coolent from front
I thought it was the water pump so I replaced the water pump
Not knowing about the weep hole so after I put new water pump on put coolent in the car and it was still leaking so I saw the hole and thought my timing cover had a hole in lol but after coming to this forum found out it was the coolent pipe
And found out I was a big job called a bmw shop here they wanted 4500 for the job
So I found there bimmer pipe and order that with the valley pan and all those gasket
After putting in new pipe putting coolent stop the leak .tryed starting my car engine turned over but battery was weak said in dash recharge battery so I took my battery to auto zone got it charged put it back in the car and tryed to start again this time it would only my a tick sound every time I press start engine so I thought my stater went bed so I got a new stater put in still something now was getting scared and worried cuz I drove the car in my self and after the coolent leak fix the engine turn over now the engine is not turning.so I decided to see is the motor turns by the crank now my problem is my crank only turn half way then locks
Then I can turn it so far back and it locks again my engine is not doing a 360

So now I don't know what's wrong engine manually only turns half way then locks
Then backward half way then locks please help me I don't know what's going on

when turning by hand is the belt off? "apparantley" other belt driven devices can seize and not let engine spin.... i dont know this first hand though...

Yes it is off

says you put in coolant pipe but not specifically that you did the valley pad.... anyway did you lose anything in the engine... I do not know everyhing that becomes exposed when doing this fix, but maybe something is stopping movement? at one specific point? if i understand correctly, you can turn it a good amount one way and a good amount the other, but not all the way areound ,right?

Absolutely correct it only turns a certain spot forward and a certain spot backwards then stops I was wondering when I took one of the valvetronic motors off to get the intake out I did not put them in removal mode .maybe one valve is touching the cylinder

having never done this I dont know for sure... jsut open it back up and verify everthing, if it moved before and doesnt now, either something is out of alignment or you left something in there that is not allowing full movement....

I took intake out and put magnit noting down there I also took valve cover off see noting maybe I bent a rod or a valve cuz of not putting valvetronic motor in removel mode and maybe the valve was down and hit the cylinder . I don't see anything else stoping the motor it won't turn more then half even with a cheetah pipe.and I broke one of the valvetronic sensor . What u guys think I should do a used motor is around 2500 bucks plus freight
And then I don't know how long that's gonna last me it's a used engine

Did you take the plugs out and try to spin it...

Ya I did still does the same thing
Right now I have the valve cover off on both sides
Intake off and all coil packs and spark plug out
Belt off fan off valvetronic motors off

Did you break a timing chain?

Starter could be hung in the flywheel would be my next thing to check.

Originally Posted by bkc0508

Starter could be hung in the flywheel would be my next thing to check.

The chain is pretty tight even when I go back and forth with it

Do u guys think I should buy a salvege BMW 745 I 2002 from Aution for 4000 or buy a used 2500 motor
See the BMW in action to tomarrow is a 2002 745i no key so that's mean no mileage also mean no engine start
So no guarantee the motor is any good the one in action is a recontrated title the car looks like it came out the paint shop with getting painted

So with out getting painted

IMHO -I would get someone else to take a second look before I decide to do an engine swap. It's probably something right in your face that you're overlooking...