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Old 03-27-2019, 06:32 PM   #1
dakattack7
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Join Date: Feb 2013
Location: az
Posts: 177
A very challenging no start situation

74 c10, 350 engine.
This engine ran great before, though it had been sitting for 10+ years and smoked.

I pulled the engine and resealed the entire thing including the valve seals which were hard and crumbled. New head gaskets AND bolts torqued in 3 stages in the correct sequence.

Reinstalled with a 4 barrel manifold (2bbl originally) and for the life of me I cannot figure out (Nor anybody who's brain I've picked) why I can't get this thing to run.

Diagnostics done:
Compression: 100 ish psi across the board at 7500 feet (Not great but plenty to run)
Fuel: It has a freshly ultrasonic'd rebuild quadrajet, though starting fluid is being used to rule out fuel
Timing: distributor is set correctly with the rotor at the number 1 terminal at top dead center of the compression stroke of cylinder 1.

All components of the distributor were replaced to no avail, including pickup coil.

I installed a double roller timing chain so I verified it was set right. I also have watched rotor and valves as I hand crank it and have verified valve timing is correct.

The spark plugs, wires, cap and rotor are new. The rotor and cap have been tripple checked for any holes or arcing and the pin is making contact and has dielectric grease.

The distributor (hei) has a new wire to the fuse box for true 12v and is receiving it during cranking and run position.

The distributor clamp was sanded along with the intake to insure a solid ground.

Spark was tested primitively by grounding a plug to the block but a bright blue spark was observed. I watched my timing light from the cab on #1 and it is consistent while cranking.

Valve lash has been reset 3 times including one time very loose to insure the valves weren't hanging open. I cleaned the carbon off the valves when it was apart.

I just removed the intake and made sure the gaskets were installed correctly and reinstalled it. I put new plugs in case the old ones were acting up from washing the cylinders initially.

The engine would sputter as if barely trying to start, and I had a few times where it sounded like it fired for the shortest instant. No backfires, timing is correct.

Distributor shaft is tight and not worn, and this is the distributor it was running well with before the reseal.

Any ideas would be greatly appreciated!
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