Engine Pulsates

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Jul 21, 2004 | 10:37 PM

Fomoco1546

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From: CENTRAL PA

Engine Pulsates

Hi, I have a 1979 F-250. I replaced the carburator a few months ago. When I go up hill over rough terrain, the truck will start to buck or pulsate. It will do this to the point that I have to push the clutch in, stop, and start out again. When I do push the clutch in, it idles fine. could this be from not enough fuel in the fuel bowl and it's causing this? I'm not sure it's even carb. related. Any help would be much appreciated, Thanks

Jul 21, 2004 | 11:32 PM

78f250RangerExplorer

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From: Yuba City

are you four wheeling or are you highway driving?

Jul 23, 2004 | 09:24 PM

Fomoco1546

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From: CENTRAL PA

Sorry, I did not explain myself. It runs super on the highway. It will pulsated in 4WD 1st gear on rocky, steep incline. Thanks

Aug 20, 2004 | 10:28 AM

1970f2504x4

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Joined: Apr 2000

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From: Summit, NJ

Did one of your spark plug wires fall off? I've had this happen a few times - it's especially noticable on inclines. Also check your fuel filters.

Aug 24, 2004 | 10:46 AM

RaleighDad66

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Joined: Apr 2004

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From: Raleigh, NC

A damper was used to help eliminate float bounce in 4X4 carbs. You might check to see if that is installed. Also, does it only have problems in one particular direction (up, down, left or right incline) or when the tank is full vs. empty? Pick-up tube in the tank or a low float setting in carb may be contributing factors.

Aug 25, 2004 | 08:31 PM

Fomoco1546

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From: CENTRAL PA

Engine Pulsates

The truck only pulsates going uphill. I adjusted the float level a little higher, but problen still persist. Anyone know how much fuel should be in carb bowl, measuring from top of carb, with air horn off? Thanks