Okay, I have a 84 k5 blazer 5.0L 305 V8 that will crank but not start. It began january 15th. It started in the morning and i drove it to the community college. When i went to leave i had started my truck up but turned it off to answer a call. When i tried to start it up it wouldn't crank, so i had campus security come out and try to jump it and it didn't work. My dad came out to get me and we tried jumping from his truck but it still didn't start. So we left if for the night. I come back the next day and my teacher was sick so i didn't have class and went to see if it would crank. It did so i drove it home. Mom took me back to the college so i could work on stuff and bring my dad's truck back home. When i got home I tried to crank the blazer and it didn't start up. Gas is going to the engine. We even replaced the line because it was kinked and put a rubber line on with an inline filter and its getting gas. We checked the ignition coil and it looks fine. Any ideas as to what is going on?

 

If I recall correctly, this engine has an HEI distributor?

 

yes it does. We got a new ignition coil today and ordered a ICM from O'Reilly's. The ICM comes in tomorrow and im hoping to put it all in as well.

 

Do some basic diagnostics before throwing a bunch of parts at it. One thing you can do is take the ignition rotor off and see if the coil burned through it and is shorting on the mechanical advance.

You need to be positive about exactly what is causing the no start condition. A couple things you can do right off the bat. Spray some hot start in the carb the next time it doesn’t start. That will rule out a fuel issue in a heartbeat.

You can also jump the hot wire that feeds primary ignition circuit voltage to the distributor,

 

We tried starter fluid and it didn't work.

 

First things first. Does it have spark or not? You never said that you checked or described how you checked.

 

This is a very common problem and what I would check first.

 

Sorry I haven't replied in a while. I was working with a local car guy but each time I tried to get him out here something happened and I decided to drop him. When I replaced the ignition coil in the blazer the ignition rotor looked fine.