I had to rebuild my 4.3 the problem that i have is that it cranks kinda hard after about 4 seconds . I was thinking maybe because i dont have the tq converter hooked up yet that when the motor comes to the compresson and power stroke the converter acts like a counter weight to help push it around. Once the motor does start it idle,s fine and revs up very fast and smooth and goes back to idle. I rechecked my timing mark on the cap at tdc and the pointer is pointed between 2-4 on the cap because thats where the terminal for # 1 is. I have never ran a fresh motor with the converter off but i acts like the ign timing is off but there is no way to set it. The battery was low and had to jump it also think this might be the problem that the battery does not have the amps to keep cranking the motor over. When the motor starts slowing down while cranking it acts like it fires at the wrong time thats (thats the hard cranking i am talking about). Please help.

 

Have a read thru this thread https://blazerforum.com/forum/tech-articles-diy-29/edi-engine-timing-24373/, sure does sound like the timing is off

 

I agree it must be a timing issue. Having the TC unbolted will not cause this. One think I know is the Crank sensor can wack out and cause hard starting along with various other issues. just my two cents

 

Did you pre-oil your engine after you rebuilt it? Did you use lube on all bearing surfaces, cam etc.? A low battery will cause this issue. The torque converter has nothing to do with your issue.

 

Yes i did pre lube and and put lube on all the bearings. Going to swap out for a fresh battery tomorrow and recheck my timing. Kinda dont think the timing is my problem like i said before once the motor is runnig it runs fine idle rev and so on. But at this point i wont over look any thing

 

Thank for the insight guys tonight i lined up the marks like it said to in the thread. And the rotor button was passed the #6 stamped in the cap. I was not able to start it tonight but i am sure this will solve my problem. Once again thanks for the help..---------------------- o yeah the autozone haynes books suck ***-----------

 

Let us know if that was the problem...if the timing is wrong, more advanced like in you case it will crank hard or kick back at ya when you try to start it, but once it is running the CKP and CMP sensors can retard the timing enough therefore it will run right as long as it is not too far out of range

 

Well i got the blazer running and is setting back in front of the house. I put the the timing in the right place and the thing starts easy,er than any other car i have very owned. Thanks for the help guy,s

 

Glad you got it fixed