Why New Diesel Generator Won't Keep Running

With a generator that has a cold engine, you will move the lever to full choke, start the engine, let it run for a few seconds, move the choke to the half choke position and then move it to the run position. This means that the choke is wide open and it's no longer restricting the flow of air into the carburetor.

If the engine will start but it won't say running, the carburetor probably has an obstruction in the tiny passageways and will most likely need to be cleaned.

It's been our experience that if the engine will only run in the full or half choke position, it's quite rare for this problem to fix itself. What you'll experience is an engine that starts but stalls shortly thereafter or one that will stay running but sounds like it's surging or stumbling.

Make sure the air filter is clean: The air filter is essential for preventing damaging dirt and debris from entering the combustion chamber of the engine. It must be in place but if it's dirty, it won't let enough air pass through it. This will cause the ratio of gas to air to be incorrect. The mixture will be "rich" so the carburetor will be getting too much gas and not enough air.

Sometimes people try running their engine without an air filter because the filter is too dirty. As mentioned, this can permanently damage the engine so don't do it. It can also cause the opposite of a "rich" air/fuel mixture. If you try running the engine without an air filter in place, it will be "lea". This just means that it's getting too much air and not enough fuel.

If the air filter is dirty and it is the kind that you can clean, follow the instructions in your owner's manual and clean it properly. If it's a paper element air filter that isn't user serviceable, replace it with a new one.

Make Sure the spark plug is in good condition: Remove the spark plug and make sure that it isn't "fouled". A fouled spark plug will have sludge or a lot of heavy dark carbon accumulations. If your spark plug looks bad, replace it with the appropriate plug for your generator's engine.

While you have the spark plug out, this is a good time to check to make sure that your engine is actually sending electricity to the plug so that it will be able to deliver a spark. The best way to learn how to do that is to look for a YouTube video. Just go to YouTube and type "Check Spark on a Small Engine".

If the spark plug is in good condition but you don't actually see a spark when you test it, the reason your generator won't run is most likely electrical. We've only had this problem one time and it ended up being a faulty on/off switch. Once we replaced the switch, we saw spark at the plug and the generator ran great.

For a new diesel generator, it also can not run under low idle for a long time. Otherwise, maybe occurs bellow problem:

1. When the diesel generator operates at low idle for a long time, the working temperature of the engine will be relatively low and the injection pressure will be low, resulting in poor diesel atomization, incomplete fuel combustion, easy carbon deposition at the nozzle, resulting in stuck needle valve and serious carbon deposition at the exhaust tailpipe.

2. The incompletely burned fuel will wash the cylinder wall and dilute the lubricating oil, resulting in the wear of piston rings and serious faults such as cylinder pulling.

3. Long time low idle and low oil pressure will cause accelerated wear of moving parts. Internal combustion engine is a heat engine. Only under the mutual cooperation and influence of coolant temperature, lubricating oil temperature and fuel combustion temperature can the engine maintain good working conditions.

Usually, diesel generators generally allowable idle running time is 3~5 minutes.