Locked Up!, What might it be? Options

[74914LE]

Just finished getting a 72 1.7ltr. ready to start up after sitting for 29 years. Went over everything in the fuel, vacuum, and ignition systems. It turned over just fine without spark hooked up to it. Now for the moment of truth. Made sure I had fuel pressure and attempted to start it.

After about 3 tries, it fired up and started running!!!! After about 20 seconds, a rattling sound started, then got worse. I immediately shut it off. Then tried to turn it over again, and it would not turn over. I then got it on jack stands and blocked one wheel to put it in gear and see if I could spin the motor by hand with
transmission in 5th gear. The wheel will turn about 1/3 a turn in either direction and it locks.

Before I drop the motor and pull it apart to check for a dropped valve or worse, though I would see if anyone wanted to weigh in on what this might be....ideas?

Thanks in advance!

[dfelz]

Like dave said, take the valve covers off to see if anything in there is giving you problems. check to make sure that all the pushrods are fully seated in the rocker arm pockets. I was reassembling my 1.7 the other day and was trying to turn the engine over and got to one spot that it WOULD NOT go past. Noticed one of the pushrods was pressed against the outside lip of the rocker arm, not in its seat, so the when the valve was fully depressed, the cam lobe still had some more to turn but the valve restricted it form moving past. When you started yours up, during the rattling maybe it knocked one of the pushrods out of position and its jamming your cam. Worth checking since its easy to get to and feel around in there. Good luck!