Polyphemus287
Member
- Joined
- Nov 9, 2015
- Posts
- 35
- Reaction score
- 0
- Location
- Richmond, VA
- First Name
- Matt
- Truck Year
- 1983
- Truck Model
- c10
- Engine Size
- 4.1
Hi All,
The issue that I am having trouble solving is that the mechanical fuel pump on 1983 C10 won't pull fuel (or enough fuel) from the tank.
Some info on the truck:
1983 c10
250 inline six
2 barrel 2ese carb (factory)
Stock mech. fuel pump
The problem first rose it's ugly head when I was driving the other day, at cruising speed, and the truck began to cut out like it was not getting enough fuel. It would idle fine, but when the throttle was applied for any duration of time (1/2 throttle that is) it would stall. As if the carb's float bowl was draining and not refilling quickly enough. I verified this by popping the hood and looking at the clear fuel filter between the fuel tank line and the pump. It had fuel but was approximately an 1/8 of the way full. Prior to this issue It would always be completely full.
From this point I ran a line from pump line to gallon gas can and the fuel filter filled itself to the brim and the truck ran fine with no issues.
I figured there was an issue with the sending unit I installed 6 months ago or a pin hole leak in the fuel lines from the tank. Also, at the same time I installed the new sending unit I installed a new fuel pump. As a result, I dropped the tank again, and removed the sending unit. It looked as clean as the day I installed it, and the tank has no visible rust or debris inside it. I blew compressed air threw both inlets, and no blockage was apparent. From this point, I ran all new steel lines from the tank to the pump, and new rubber hose sections. I also installed a new clear fuel filter.
I reinstalled everything and the pump only pulled a splash of fuel into the clear filter. I primed the float bowl in the carb 3 times and the engine ran about a minute each float bowl prime. I installed a new mechanical pump I had lying around still had the same result. I verified that this pump was working with a vacuum gauge. It pulled 16hg (spec 15 hg). I also put my finger on the inlet and outlet of the pump while cranking and it is defiantly pulling vacuum, and pushing air at the outlet. Suspecting some vapor issue in the tank I removed the gas tank cap, and primed the float bowl. The result was that the filter filled approximately halfway full. I primed the bowl two more times and the filter remains 1/2 full, and no fuel at the outlet of the pump.
At this point I am bit lost, because I am unsure what would prevent the pump priming. I have rechecked my new lines for kinks, and for leaks. I also re-tightened all hose clamps on the rubber fuel lines. All would appear to be kosher. Anyone have any ideas regarding this? Any help is appreciated!
The issue that I am having trouble solving is that the mechanical fuel pump on 1983 C10 won't pull fuel (or enough fuel) from the tank.
Some info on the truck:
1983 c10
250 inline six
2 barrel 2ese carb (factory)
Stock mech. fuel pump
The problem first rose it's ugly head when I was driving the other day, at cruising speed, and the truck began to cut out like it was not getting enough fuel. It would idle fine, but when the throttle was applied for any duration of time (1/2 throttle that is) it would stall. As if the carb's float bowl was draining and not refilling quickly enough. I verified this by popping the hood and looking at the clear fuel filter between the fuel tank line and the pump. It had fuel but was approximately an 1/8 of the way full. Prior to this issue It would always be completely full.
From this point I ran a line from pump line to gallon gas can and the fuel filter filled itself to the brim and the truck ran fine with no issues.
I figured there was an issue with the sending unit I installed 6 months ago or a pin hole leak in the fuel lines from the tank. Also, at the same time I installed the new sending unit I installed a new fuel pump. As a result, I dropped the tank again, and removed the sending unit. It looked as clean as the day I installed it, and the tank has no visible rust or debris inside it. I blew compressed air threw both inlets, and no blockage was apparent. From this point, I ran all new steel lines from the tank to the pump, and new rubber hose sections. I also installed a new clear fuel filter.
I reinstalled everything and the pump only pulled a splash of fuel into the clear filter. I primed the float bowl in the carb 3 times and the engine ran about a minute each float bowl prime. I installed a new mechanical pump I had lying around still had the same result. I verified that this pump was working with a vacuum gauge. It pulled 16hg (spec 15 hg). I also put my finger on the inlet and outlet of the pump while cranking and it is defiantly pulling vacuum, and pushing air at the outlet. Suspecting some vapor issue in the tank I removed the gas tank cap, and primed the float bowl. The result was that the filter filled approximately halfway full. I primed the bowl two more times and the filter remains 1/2 full, and no fuel at the outlet of the pump.
At this point I am bit lost, because I am unsure what would prevent the pump priming. I have rechecked my new lines for kinks, and for leaks. I also re-tightened all hose clamps on the rubber fuel lines. All would appear to be kosher. Anyone have any ideas regarding this? Any help is appreciated!