If your generator wont start, I bet the carburetor is toast, here’s how to replace it. First, watch our how-to video.
When Your Generator Wont Start:
I bet the last time you ran your generator was over a year ago. In that case, the carburetor is full of old gas that has broken down into gunk, and clogged the carb. Now, you can take apart the carburetor and clean it, even buy a rebuild kit. But for most of us, this is a higher level of skill than we posses. We can, however, buy a replacement carburetor and install it. You have the skills to do this, as long as you watch GardenFork, I bet.
First step is to order a new carburetor (here is one example, find one that matches your engine). Find the engine model number stamped on the engine somewhere. This may be several lines of numbers, and they are all relevant. If you can, photograph the numbers with your smart device. On Briggs & Stratton engines, the numbers are often on the valve cover. The numbers on the generator chassis are probably not the ones you need, find the engine numbers. Search online for “engine serial number location (name of your generator)”. I have found that there is sometimes one replacement carb that is used on many small engines for a certain brand. I had to search a bit to make sure I was getting the right carb, but the comments made by other purchasers really helped.
Your replacement carburetor may come with several choke handles, as the new carb fits several models of engine. I had to cut a small piece of metal off the back of the air filter mount to allow the new carb choke handle to fit properly. Not a big deal.
Check out the instructions that come with the carb. You may need special torx bits. I did, and only learned this after I started the job. Fun.
To remove the old carburetor, start by draining the old gas out of the fuel tank. Turn off the fuel line that runs to the carburetor, pull the hose off the carb, and put it into a gas can. Turn on the valve, open the fuel tank cap, and drain. Don’t dump this gas in the woods or a creek, OK?
Big thing to remember: take photos throughout this process, so you can refer to how it all came apart, OK? Remove the spark plug wire from the spark plug. This may seem unnecessary, but its a good practice to get into, especially if you have a electric start generator… Now remove the fuel line from the carb and remove the air filter and the frame that holds it to the carburetor.
The carb may have what look bolts or nuts that are star shaped, these are usually called Torx nuts. You may already have a set of tools to remove these, or you can borrow them or you can buy them.
Remove the governor control rod and spring assembly. A new rod and spring may come with your carb, use the new one, but hold onto the old one in case there is an issue. The rod may be concealed under a plastic or metal shroud, it may take some time to remove it.
Remove the carb from the engine carefully. There is at least one gasket that may tear, and you may not have a new one to replace it. Some gas may drip out of the carb, that’s ok.
The new carburetor will go back in about the same way the old one came out. The hardest part is getting the governor control rod and spring reconnected. There should be a diagram that comes with the new carb showing how it connects.
Also the choke handle may be different or require a little cutting to get it fit. The carb I bought came with several choke handles, and you may have to remove and replace the one that is installed on the new carb.
While you are doing the generator repair, you might as well put in new spark plug and change the oil. Spark plugs die out suddenly, and you’re already deep into small engine repair mode, this will take 2 minutes.
If your generator wont start and has been sitting, I bet the oil is the color of mud. This is a bad thing. Muddy oil can mean there is water in the oil, and will ruin the engine. Take the waste oil to a oil change or car repair shop, they will recycle it for you. Don’t dump it in your yard.
Going forward, always use gas stabilizer in your small engines. Then you don’t have to wonder what to do when your generator wont start. Whenever I fill up my gas cans, I immediately add in the gas stabilizer. My engines start on the first pull, even after a winter in the garage.
A good follow up to this is our small engine tune up and oil change video: