Crank, no start.

[tdash]

2000 k3500 crank, no start. Bought a truck that has had tons of parts thrown at it. Just about everything fuel, spark related has been replaced. Only time I got it to start is backing it into the shop, just turned the key and it started. Ran terrible then died. Has good compression, spark and is holding 55psi fuel with key on. Verified distributor is timed properly on TDC 1. Passlock is bypassed. Ether doesn't help. It did make loud pop out of the exhaust after cranking for a while and once out of the intake. I would on heavy duty diesels, first time working on a gasser that is this involved.
My next steps are to vacuum test and oil pressure test. Quite a bit of gunk up top when I pulled valve cover.
Any other ideas?

 

[618 Syndicate]

Passlock bypassed how?

 

[Drunkcanuk]

2000 k3500 crank, no start. Bought a truck that has had tons of parts thrown at it. Just about everything fuel, spark related has been replaced. Only time I got it to start is backing it into the shop, just turned the key and it started. Ran terrible then died. Has good compression, spark and is holding 55psi fuel with key on. Verified distributor is timed properly on TDC 1. Passlock is bypassed. Ether doesn't help. It did make loud pop out of the exhaust after cranking for a while and once out of the intake. I would on heavy duty diesels, first time working on a gasser that is this involved.
My next steps are to vacuum test and oil pressure test. Quite a bit of gunk up top when I pulled valve cover.
Any other ideas?

Have you checked out the factory service repair manuals yet?
They are in the engine and performance section, in a sticky. Lots of trouble shooting in them.

Tossing it out there....check ALL the fuses??
The vats can definitely be an issue.

 

[tdash]

Passlock bypassed how?

2200 ohm resistor between two wires going to tumbler.

 

[Moofus02]

Plug in a scanner and look at coolant temp sensor. When they fail they read like 40 below and truck won't start because it's so pig rich

 

[tdash]

Have you checked out the factory service repair manuals yet?
They are in the engine and performance section, in a sticky. Lots of trouble shooting in them.

Tossing it out there....check ALL the fuses??
The vats can definitely be an issue.

No, I’ll take a look.

Plug in a scanner and look at coolant temp sensor. When they fail they read like 40 below and truck won't start because it's so pig rich

had a scan tool on it. I think I remember seeing it at 59*

 

[GoToGuy]

What vacuum test? When you turn key to " on or run " not start position , do you hear fuel pump prime?

 

[Schurkey]

2000 k3500 crank, no start.

WHAT ENGINE???

Has good compression,

Define "good".

spark

TO the plugs, or across the plug gap? In other words, are the spark plugs fouled/broken, or contaminated/conductive porcelain?

and is holding 55psi fuel with key on.

What is GM spec for fuel pressure?

Verified distributor is timed properly on TDC 1.

What is the cam offset? Within spec?


Exhaust restricted? Catalyst(s) plugged, pipes crushed?

 

[618 Syndicate]

2200 ohm resistor between two wires going to tumbler.

Any method other than tuning it out is unreliable. Not saying that's your issue here, but definitely don't rule it out.

 

[Scooterwrench]

What is the cam offset? Within spec?

My thought when he said it was popping back through intake.