MG Car Repair: locked up, crank pulley, pulley bolt

Question
hello
i have a 1975 mg midget. it turned over perfectly fine since i got it but never started.i went to time it the other day and i timed it 10 degres BTDC but then i realized it was supposed to be 2 degres ATDC. i put the car in 4th gear and pushed it back and forth to throw it out of timing so it would turn over again. it started turning over perfectly fine. then i hooked up my timing light to time it correctly and all of a sudden it wouldnt turn. i turned it over manuelly to see if it would turn over and it wont. it turn for like 3 seconds then on the last compression it just stops. please help!
                                             -rob

Answer
Hi Robert,
It is very unusual for an engine to lock up just turning it over manually.
Take it out of gear and try to rotate the crank shaft by the front crank pulley bolt to see if the engine is locked up or the transmission locked up. Also, note if there is any movement of the crank in either direction and if so how much? A locked condition in one direction only indicates something on top of a piston. A very slight back and forth movement indicates a piston or rings seized to the cylinder wall. No movement at all can be a seized rod or main bearing.
If you had bumped the starter a few times it could be a locked up starter bendix gear on the flywheel ring gear which also gives you a crank that does not move at all. This type of lock up can be broke loose by just loosening the starter bolts and put the car in 4th gear and rock the car forward and aft hard.
The only other thing I can think of is something in the timing chain to cause a lock up.
Howard