This page has been translated with google translate, there may be errors in the stories.

Engine does not idle but under load.

Idle speed is not properly adjusted.

The fuel pump has a set screw with which it can be adjusted. Usually this screw is located against the throttle on the fuel pump.

Alternator defective.

If the charge regulator of the alternator is broken, the alternator can start charging to the maximum, which means that, especially for small engines, the power the alternator delivers to the flywheel is so great that the engine does not want to start. Loosen the V-belt and hit the mor or the dynamo is broken.

Injector out of order.

With older engines, the spray pattern may no longer be good, so that the fuel is not atomized correctly and does not ignite completely. The atomizer must then be overhauled.

Fuel pump control rod is sluggish.

Dirt and rust can cause the throttle on the fuel pump to go heavy. Cleaning and spraying with WD40 can help.

High pressure pump discharge valve not OK.

Broken spring and / or discharge valve seat worn / corroded.