Engine stalling

[Kip7143]

Hi all!

I have two vehicles, one with a 350 Chevy 73 motor and the second with a 4.2L 81 chev straight 6. Both motors are acting very similarly except the 350 is running a little more consistently. I’ll walk through everything I’ve done on both.. but I’m kind of at a dead end here.

1981 C10. Truck dies at idle in gear. Usually I can have it running in park but the idle is high and the truck sputters a lot, and is very rough. I can throttle the truck and it continues to run. I can even drive it down the road.. but once I let off the throttle it will die. Usually pretty suddenly.

So far on the truck I’ve replaced all vacuum hoses. The dist cap, pick up, coil, rotor, plugs and wires. I’ve timed it in park, idle a little higher then normal. I have taken the carb off the truck and done a visual but nothing seems incorrect. Still the truck is stalling as soon as I go drop it into drive. The carb is a Rochester verajett II. The idle mixture screw was sealed but appears to be uncovered. I have not done anything else to the carb. I’m thinking rebuild the carb?

The second is the 350. The vehicle was parked for close to 10 years and I’m slowly waking it up. The carb was freshly rebuilt, then cleaned the points, set timing, and finished the final tuning of the carb. I drove the car for about 2 weeks when the fuel tank dislodged everything that had rusted in there and clogged the system. Almost a year later I have a new tank in, new sending unit, in-line filter and inlet screen.

I filled it up with fuel and it started quite easy. Ran pretty decently. After my 20 ish minute drive yesterday it started to bog while in drive. You could hear the rpm changing as I was holding the throttle still. When I got home and put it in reverse it stalled. I had to two foot it back In the garage. As I was looking under the hood and doing minor carb adjustments I noticed the fuel in the Inline filter was going back down to the pump. So I ordered a new pump and put it in today.

I took it for another drive, this time only about 5-6 minutes and it was really strong off the bat but as it warmed up it started to have the same symptoms. I should mention- no choke on this motor. Carb is a edlebrock 1405

This vehicle is still on points. Question though: would poor timing stall the vehicle, but let it throttle up nicely? I’m going to check timing again tomorrow but I don’t think timing is causing the bog issues.

Any ideas or Input is greatly appreciated. I am considering changing from points to EI. I just want to drive my summer toys!!

Thanks in advance.