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Cummins Super 250 Need Help


iivydriff
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Ive got an old 74 model Autocar. It has a Super 250 Cummins in it. It ran like a top then I parked it. It has set for several years. Ive been trying to get it fired up I need to sell the ole girl. ive made sure its got fuel to the pump. But im at a loss of what to do next. It does sound like its hitting on one cylinder. It will smoke when turning it over. Do I need to bleed the fuel somewhere on top of the engine? It has the old internal fuel lines. There are two plugs in the front of the front head. Could I pull one of the plugs out and make sure fuel comes out at that point. The lower plug should bleed the incoming fuel line. The upper plug I I assume is on the return line. I know these old engines are rare, hoping to find someone to help me out here. Ive did all the basic stuff drained almost all the fuel added new fuel. made sure its all primed up all the way to the pump. It will hit a little bit, but I just need to know if I need to bleed somwhere else that Im missing.

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Test your fuel shutoff solenoid on top of fuel pump, should be getting 12 volts, on some models there is a override thumbscrew, in front of the fuel shutoff, turn in all the way, if engine starts the only way to shut down is by turning screw back out. Do not take out the two plugs on heads. I got more ideas if that doesn't do it.

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Ive got an old 74 model Autocar. It has a Super 250 Cummins in it. It ran like a top then I parked it. It has set for several years. Ive been trying to get it fired up I need to sell the ole girl. ive made sure its got fuel to the pump. But im at a loss of what to do next. It does sound like its hitting on one cylinder. It will smoke when turning it over. Do I need to bleed the fuel somewhere on top of the engine? It has the old internal fuel lines. There are two plugs in the front of the front head. Could I pull one of the plugs out and make sure fuel comes out at that point. The lower plug should bleed the incoming fuel line. The upper plug I I assume is on the return line. I know these old engines are rare, hoping to find someone to help me out here. Ive did all the basic stuff drained almost all the fuel added new fuel. made sure its all primed up all the way to the pump. It will hit a little bit, but I just need to know if I need to bleed somwhere else that Im missing.

On top of fuel pump is a fuel switch, try turning the switch to manual ( in is on) see if that helps.

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Test your fuel shutoff solenoid on top of fuel pump, should be getting 12 volts, on some models there is a override thumbscrew, in front of the fuel shutoff, turn in all the way, if engine starts the only way to shut down is by turning screw back out. Do not take out the two plugs on heads. I got more ideas if that doesn't do it.

Ok will look into that

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