350 - Cranking, won't fire

[kenn]

electric fuel pump ? takes a bit for gas line to fill up if its not, squirt little gas in carb see if she will fire (watch out for backfires thru carb if 180 out)

 

[theblindchicken]

Working on the truck today.

Got the distributor all set up again. Appeared to be 180 out, but now having another issue.

Truck will fire up easily, but then the throttle will run away right up to 2k rpms, hold for a couple seconds then tank to 600-800 then die. All without actually applying the throttle.

Currently have vacuum lines hooked up. I can hold 2k with a little tap of the throttle here and there as well.

 

[theblindchicken]

Also smoking through carb as well.

You must be registered for see images attach

 

[Snoots]

Intake leak?

Can't really tell but, do you have a pholenic spacer between the intake and carb?
If not, you REALLY need one or you'll have more hot soak issues than you can shake a stick at.

 

[theblindchicken]

Intake leak?

Can't really tell but, do you have a pholenic spacer between the intake and carb?
If not, you REALLY need one or you'll have more hot soak issues than you can shake a stick at.

I have one of the 3/16-1/4" carb gaskets. I would need to get a new fuel line if I get a thicker spacer than that between the carb and intake manifold.

I'm not sure what you mean by an intake leak.

Appreciate the quick help though.

 

[Snoots]

If it starts at first (usually there be a lot of gas there) it'll run then, start to lean out and rev like mad and die.
To me, that's the symptom of an air leak under the carb or the intake manifold to block.
Could be a massive leak in the throttle body too.

I should elaborate.

The throttle body develops leaks where the butterfly shaft goes thru the throttle plate. You can check for this by squirting a touch of starting fluid at that point with the engine running (if you can get it to run long enough).