pearlmoto
Junior Member
- Joined
- Jun 7, 2017
- Posts
- 6
- Reaction score
- 2
- Location
- Dallas
- First Name
- Thomas
- Truck Year
- 1986
- Truck Model
- K30
- Engine Size
- 5.7L
Hello everyone,
My name is Thomas from Dallas and I have a lovely all original 1986 K30 Silverado with 23K miles, 5.7L LT9.
It came from an estate and I have been using this truck as my daily driver.
I have ironed out a few wrinkles that can be expected from a truck that wasn't used very often, but I have recently been presented with a problem I simply cannot figure out.
I recently restored function of both gas tanks by replacing the fuel selector valve. I had run about 500 miles between the tanks, alternating between left and right. I filled up and about a quarter mile down the road, the truck dies.
It feels like a fuel starvation issue, but the accelerator pump is working and further tests had the fuel pump sending out an acceptable volume of gas - it is an AC Delco pump I replaced about 1000 miles ago. I set the fuel pump up on a remote gas can to eliminate the selector valve or lines before it as suspect - the truck ran the same off a remote can. I concluded that I could focus on the fuel system from the pump to the carb.
I figured putting an unused gas tank back in service may have put some silt through the system, so I pulled the carb back off the truck and rebuilt it (I had already rebuilt it about 1000 miles ago). I did find some silt in the bowl, and also a brass breather tube had come loose from the airhorn in the carb. I fixed these issues and reinstalled the carb. There was no change when I tried starting the truck.
I did the next logical thing - replace the fuel pump. Again. I go to start the truck - same behavior.
There's got to be something I'm missing. There's ignition verified by 12V to the coil - the ignition control module, cap, rotor, plug wires, and coil are all new and all AC Delco. I replaced the plugs about 600 miles ago and checked a few - they look good.
The vac canisters are all new; I replaced them when I did the selector valve because the failed valve bled gasoline through the vent line and fouled the canisters.
I have also verified 12v to the choke, and the choke mechanism is also new.
Here's a video of my trouble. Can anybody voice their thoughts on what to attack next? I was so frustrated yesterday I chucked my ratchet across the yard.
My name is Thomas from Dallas and I have a lovely all original 1986 K30 Silverado with 23K miles, 5.7L LT9.
It came from an estate and I have been using this truck as my daily driver.
I have ironed out a few wrinkles that can be expected from a truck that wasn't used very often, but I have recently been presented with a problem I simply cannot figure out.
I recently restored function of both gas tanks by replacing the fuel selector valve. I had run about 500 miles between the tanks, alternating between left and right. I filled up and about a quarter mile down the road, the truck dies.
It feels like a fuel starvation issue, but the accelerator pump is working and further tests had the fuel pump sending out an acceptable volume of gas - it is an AC Delco pump I replaced about 1000 miles ago. I set the fuel pump up on a remote gas can to eliminate the selector valve or lines before it as suspect - the truck ran the same off a remote can. I concluded that I could focus on the fuel system from the pump to the carb.
I figured putting an unused gas tank back in service may have put some silt through the system, so I pulled the carb back off the truck and rebuilt it (I had already rebuilt it about 1000 miles ago). I did find some silt in the bowl, and also a brass breather tube had come loose from the airhorn in the carb. I fixed these issues and reinstalled the carb. There was no change when I tried starting the truck.
I did the next logical thing - replace the fuel pump. Again. I go to start the truck - same behavior.
There's got to be something I'm missing. There's ignition verified by 12V to the coil - the ignition control module, cap, rotor, plug wires, and coil are all new and all AC Delco. I replaced the plugs about 600 miles ago and checked a few - they look good.
The vac canisters are all new; I replaced them when I did the selector valve because the failed valve bled gasoline through the vent line and fouled the canisters.
I have also verified 12v to the choke, and the choke mechanism is also new.
Here's a video of my trouble. Can anybody voice their thoughts on what to attack next? I was so frustrated yesterday I chucked my ratchet across the yard.
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