Gas Tank Baffles?

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cstew47

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I have a problem when going up a steep hill. The engine quits due to a lack of fuel. I have rebuilt the carb and the fuel pressure is good when on a level grade. I am wondering if there are baffles in the gas tank. If not, can they be installed. The tank is OE for my 78 K5. Are there any other thoughts on this?
 

Bextreme04

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You can get a tank for an 87-later K5. Its a direct replacement but has a baffle inside for the fuel injection pump to sit inside on the TBI blazers. I have one retrofitted on my 1980 K25 instead of the saddle tanks.
 

fast 99

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There has to be an issue with fuel delivery other than the tank. GM could never produce a vehicle like that. Was the filter and fuel volume checked, not just the pressure?
 

75gmck25

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Stock gas tanks for carbureted trucks have no baffles.

My ‘75 K25 has fuel delivery issues if I let it get too low on gas. Started to cut out last week going up a moderate hill, so I switched to the other tank. At the gas station it took a little over 19 gallons in a 20 gallon tank, so it was getting pretty low. Gauge was showing right at the empty line, so I guess I need to pay more attention.
 

WFO

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I have a problem when going up a steep hill. The engine quits due to a lack of fuel. I have rebuilt the carb and the fuel pressure is good when on a level grade. I am wondering if there are baffles in the gas tank. If not, can they be installed. The tank is OE for my 78 K5. Are there any other thoughts on this?
Could your float level be set too low?
It takes a lot more fuel to go uphill.
I'd also pull a fuel line and check for fuel pump volume.
 

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Stock gas tanks for carbureted trucks have no baffles.

My ‘75 K25 has fuel delivery issues if I let it get too low on gas. Started to cut out last week going up a moderate hill, so I switched to the other tank. At the gas station it took a little over 19 gallons in a 20 gallon tank, so it was getting pretty low. Gauge was showing right at the empty line, so I guess I need to pay more attention.
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fast 99

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Had the same issue with a K20. Took 3 fuel pumps before I got a good one. It ran fine except when accelerating hard to blend in with traffic on the freeway. It really ticked off a few drivers. Was hard for me to believe 3 new pumps were bad out of the box. Replaced a bunch of unnecessary parts before figuring it out. That would have been avoided had the volume been checked first.

That's one of those experience lessons, I knew better
 
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cstew47

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I wonder if a PO put a sender for a 25 gal tank in my 31 gal tank. That may explain why it would starve on steep hills.
 

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