six cylinder won't start in the morning

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Mickey1977

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I have been trying to solve why I have to pour gas into my single barrel carb on the very first start of the day. It is an inline six with a manual three speed. I have a new manual fuel pump, new fuel line from pup to carb, and new filter. After the first start it starts right up. I have a manual choke that closes the shutter on the carb properly. arfter replacing everything, it still won't fire up on first start, and cuts out at fift mile an hour. Any suggestions?
 

Matt69olds

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Let it sit overnight. Don’t move the throttle, remove the air filter housing. Once again, don’t touch the throttle, open the choke plate. Look down the throttle bore, and look at the accelerator nozzle while you move the throttle. You should see a solid stream of fuel. If not, either the carb is leaking fuel, or the accelerator pump check ball is leaking.

Inspect all the fuel lines, make sure none are cracked or dry rotted. If it’s stalling or dying at 50mph it sounds like the pump isn’t able to pull full correctly. If there is a hole in the fuel line, the pump will suck air instead of fuel.

More than likely you won’t see fuel dripping. Look for stains or discoloration around the lines, especially the clamps. The steel lines tend to corrode under the clamps.
 
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Mickey1977

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Rebuilt Carburetor and replaced all rubber hoses connecting steel Fuel lines. Vehicle start in the morning but stalls at 25mph in second and 35 in third. Checking the fuel lines for corrosion. Also checking the timing.
 

squaredeal91

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Sounds kinda like fuel starvation. Will it stay idling?
 

Rickf

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Does it sound like it cuts out at a certain engine rpm? Maybe wire in a tach to check.
 

TotalyHucked

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Also keep in mind, the pump being new means nothing these days. Could be bad out of the box
 

fast 99

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Really can't guess when diagnosing.

I personally had 2 new fuel pumps on the same SB that worked for about 15 miles before pooping the bed.

Start with basics then move on to more obscure or expensive possibilities. Fuel, intake, compression, spark, exhaust.
 

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