won't start 89 blazer4.3 vortec

You mean the motor has been apart just before it was sold and you've never seen it run since it's been back together? The intake valve can be closed at TDC as well the top of the exhaust stroke. You need to find TDC by aligining the groove on the balancer with the 0 degrees index on the timing chain cover with both valves being closed on number one. At this point you can then insure the distributor is properly indexed to the #1 position.

Something is out of time because the intake fully closes well before TDC on the compression stroke. (somewhere between 100 and 120 BTDC) Sounds like cam is out of time if you are checking it correctly. This would definately keep it from starting and running.

----------------- TheSnoMan.com

Ok well i took the front of the motar apart and it apears that the timing chain and the gears line up properly ( as diagram in chiltons).I i do need to adjust the distriburor a bit but i will have to do that tomorow.I was sick all day and had to stop ill put it back together and ill see what happenes Thanks for the advice.

YOu know after thinking about this somemore I am wondering if you were rotating the engine bacwards and 360 degrees out of sync with timing (720 degrees to a complete cycle). If you did it would make sence that you saw the intake valve just closing because when spun the other direction it would just be starting to open to draw mixuter in to compress it during the next 360 degrees of revolution. This would mean timing was exactly 360 degrees off (180 related to cam) and had no mixture to ignite so it would not even to begin to try to fire because it would be trying to "light" empty uncompressed cylinders.

----------------- TheSnoMan.com

I had a starting problem with my truck 4.3 vortec it was standing for some time and the injector was plugged