Hello,
Sounds like you may have a basic fuel mixture problem. You can verify this by a simple test.
With the engine running disconnect the linkage rod at the injection pump, between the injection pump and the "cross over rod" . If you move only the cross over rod linkage going to the intake venturi, and the engine decreases in rpms then the engine may be running too lean. If the engine stays the same or only increases 100 rpms or less, the mixture should be good. If the engine increases over 100 rpms the mixture is to rich.
Verify the information by next just moving the injection pump lever. If you move the lever down and the engine increases in rpms the mixture is too lean. When the mixture is correct, the engine will stay at the same rpm or increase less than 100 rpms. Also when the mixture is correct the engine idle will not increase when the injection pump linkage is moved .
This "linkage mixture analysis" can be conducted at idle and any other throttle position.
Be aware that this will tell you the mixture condition but may not tell the cause of a problem but may verify that you have a mixture problem.
Some posible causes of fuel mixture problems are linkage wear, linkage set-up, incorrect fuel pressure or volume, plugged air or fuel filters, leaking or mal functioning starting devices or warm up devices, mal adjusted or faulty fuel injection pump or injectors, a simple mxture adjustment or a combination of some of the above. Start with the simple test first and hopefully a simple adjustment will do the trick. Get back with us with your findings! The "Linkage Tour" is a good place to start.
