Carb sputter uphill

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ET_77K25

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Halifax
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Evan
Truck Year
1977
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GMC K25
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454
Hi folks, I'm new to the forum and I'm hoping someone can help me out with a carb/fuel question.

My '77 K25 w/ 454bbc sputters going up hill. I can see the fuel gauge bouncing around so I'm sure the fuel is sloshing around in the tank, but I should still have lots of fuel. It's almost like the fuel pump is being starved of fuel.

What can I check to find out what the problem is?
 

fast 99

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Brian
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K20
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350
Fuel pressure, volume and filters. New fuel pump quality is horrible. If everything checks out [unknown what carb] possible metering rod stuck.

Bouncing fuel gauge is likely caused by the gauge itself. Shouldn't be an issue provided there is enough fuel in the tank.
 

SQ HAF KRU

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1/2 Ton Crew Cab
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You don't say what brand of carb you have, if its a carter, or Edelbrock, you might check float bowl level, sounds like the float level is to low, and fuel in the bowl is running to rear...aka fuel starvation. Just thoughts
 

PrairieDrifter

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Fuel flow and float level. Timing could also be an issue, too much timing that is.
 

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