Dane
04-03-2014, 09:46 AM
I just came from talking with my dealer about my 550. It is having trouble starting when hot and in general acts like it's running rich. Pulling the plugs confirms it. The carburetor is not adjustable and apparently Deere has issued a notice about the 550. It is prone to fowling the plugs and getting excess fuel in the cylinders when it is "short run". Basically a lot of short trips & idling do not get the engine up to temperature to burn off the carbon and excess fuel. In addition to fowling the plugs the excess fuel can wash down the cylinders and end up diluting the oil.
Two recommendation from the dealer:
1. The air filter must be kept clean. The carburetor is not adjustable and seems to be set rich to begin with. The slightest clogging of the air filter restricts the air supply causing it to run even richer. With my usage I notice the engine missing when I stomp on the gas, harder starting and roughness after starting after about 35-40 hours on an air filter and know it's time for a change. A new air filter resolves the problem.
2. Run it hard. The engine needs to get fully hot for a while. Idling and short trips do not sufficiently heat the engine. It needs a load like driving at high speed or pulling a load. Something that will keep the gas pedal smashed to the floor for 10 minutes and "no", reving at idle does not count. It must have a load to get the engine up to temp.
Two recommendation from the dealer:
1. The air filter must be kept clean. The carburetor is not adjustable and seems to be set rich to begin with. The slightest clogging of the air filter restricts the air supply causing it to run even richer. With my usage I notice the engine missing when I stomp on the gas, harder starting and roughness after starting after about 35-40 hours on an air filter and know it's time for a change. A new air filter resolves the problem.
2. Run it hard. The engine needs to get fully hot for a while. Idling and short trips do not sufficiently heat the engine. It needs a load like driving at high speed or pulling a load. Something that will keep the gas pedal smashed to the floor for 10 minutes and "no", reving at idle does not count. It must have a load to get the engine up to temp.