Help! Not starting...

[GMDiesel]

Hello everybody I'm new to this website, and also a new square body owner. I bought a 1984 6.2 l diesel Blazer in January. It was running fine with a little hard starting now and then I assumed it was from the cold weather. 2 weeks ago it was turning over just would not start. I had to get it towed to my house where I began to try and find what was wrong with it. Since then I have replaced the starter,the batteries, glow plugs, fuel return lines, and fuel pump. However it is still cranking but not turning on and it will do that until the batteries die. Can anyone help me? I am not a mechanic but I bought the car with the intent to teach myself how to restore it.

 

[1987 GMC Jimmy]

How do the rubber lines look like at the tank right off the sender? If all those’re cracked, that’s sucking air into the lines and hampering the fuel you’re getting if there’s any at all. You can always test this by running a hose between a can full of clean diesel and the lift pump suction side. If fuel’s getting past there, I would look into the glow plug control circuit and possibly the injection pump taking a dump. Check out the diagnostic flow charts for a crank, no start condition in the reference library for 1984 light duty trucks, specifically diesels. I wish I knew more, but someone will come along who does. I know fairly little about 6.2/6.5s specifically, and I’m pretty mediocre on diesels in general.

 

[bedwards]

Are you getting fuel at the injectors? When a diesel cranks but doesn't fire, usually it will have white vapor out the tail pipe. I too know little about your truck but fuel air and compression should make it fire. If its mechanical pump there should be a way to prime it. Just a tiny sniff of starter fluid in the air intake should make it fire. Don't use too much will blow the head gaskets.

 

[80BrownK10]

Fuel filter?? Has it been changed?

The factory one is square and on the firewall. There is a nipple that you unscrew and pull the power wire on the injection pump and crank till fuel squirts out, then you close it off and the reconnect the wire and the system is primed.