On any machine who's average age is thirty five, give or take a few years is going to have issues regardless of how well maintained it may have been. However, it always amazes me at how durable many of the various parts are & the high level of reliable service they give us over all the years. And surprisingly, even when they are abused well above & beyond reasonable expectations, they still perform reasonably well.

There are a few parts on tractors that for some reason are quickly blamed for all the troubles an owner/operator can assign to a machine. These parts range from belts to bearings. Seals & bushing's. From ignition points to distributor. And last but not least the carburetor. Whenever a tractor's behavior can not be rationally explained, you can always blame it on the carburetor. Or almost always as some people would have you believe. While it may be true that carbs (not the kind you eat) may be the cause of some problems, the amount of blame they receive is way out of proportion to the actual problems encountered.

Perhaps this is because many people do not have adequate understanding about this part & how it functions. Many of the problems that the owner/operator blame on the carb are not related at all to the carb. Many issues in the fuel system, ignition system & the engine are placed on the carb. Maybe because there is a false hope that the problem lies within. But more often than not, the problem is elsewhere in the system. Perhaps tinkering around with the carb allows the time necessary to give serious thought & research on how to find the actual problem.

But enough said on this. I have only made mention of it so that before you spend time & what could be a lot of money, you might want to really assure yourself that your going down the right path. I am not going to attempt here to explain the science behind the carb & how it works on your tractor or any other piece of equipment that has one. There are many fine sources of information ranging from basic to complex to describe all the functions of this component. I will leave it up to you to decide how deep into detail you want to plunge. This article is intended to give you something to think about regarding carbs.

Some might argue this point, but basically there is nothing in the makeup of a carburetor that is prone to wear out. However, they can develop all sorts of abnormalities due to gum & varnish deposits by stale or contaminated fuel, introduction of fuel additives that can damage non metallic parts such as "O" rings, seals, gaskets & diaphragm's. And more often than not, damage caused by persons trying to make adjustments to the high & low speed idle systems, or trying to remove parts that should never be removed at all.

On John Deere models, your best guide to rebuilding a carb is the shop service manual or technical manual. It will give you directions specific to your model & the carb that is on the machine. While carbs vary by manufacturer & by engine size, they all have the same basic repair parts. However you do not want to mix & match parts from various carburetor's or rebuild kits. To do so would defeat the purpose of the rebuild. As an example, most if not all fuel inlet valves & valve seats are matched & should never be inter changed. When directions call for both inlet valve & valve seat to be changed as a set from one rebuild kit, make sure you follow this direction or you will encounter problems.

If this is the first time you are trying your hand at rebuilding, it's not all that difficult. But it will require you to have some patience, a clean work bench, and a few small size tools like jeweler's screw drivers, a very slender punch, a small hook or pick tool similar to those used at the dentist's office. These along with a pair of pliers & a magnifying glass should be about all that you will need. These are only suggested tools which you may or may not need all of them. But if your already into taking things apart, you're more than likely to have everything you need to do the job. Before you ever start to work on your carb, make sure you understand all directions as given in the service manual. Or, if a manual is not available to you, I suggest you do read & understand the construction of the carburetor before you take it apart. Also be aware that some carbs have very small non metallic gaskets & seals. Some of these parts must be installed with the proper side up or down as the instructions call for. Hence the magnifying glass to help you verify the proper orientation.

For reference, you might want to look over the Tecumseh Technician's handbook for 3 to 11 hp 4-cycle L head engines. While this information essentially applies to Tecumseh carbs, you will learn a lot from it that can be applied to Kohler & Briggs as well. All carbs share similarities. Also check on books written by Paul Dempsey, "The Complete Handbook of Lawn mower Repair" & Dempsey's "How To Repair Tecumseh Engines". In addition, many times you can find exploded parts drawings on the manufacturers website. I believe Kohler has drawings & manuals on their site along with parts lists. If your new at this I strongly suggest you review at least one of these information sources.

The next thing you need is a clean work bench and a clean tin can or two to hold part as you take them off the carb for cleaning & inspection. You will also need a large enough can to soak your carb body in cleaner to desludge it. Try to have three or four cans available before you start. Having to raid the pantry & convince your wife to open up cans of food not needed always causes a problem in my house, so you might want to avoid this.

Having done a few carbs, I have gotten good results with rebuilding them, but it came at a price. In the beginning my curiosity & enthusiasm to discover the wonders of the carb went beyond my control. I gave no attention to what parts should be removed & which should remain. I also made no notes on how things looked on the carb, or their location. And I found that I always had parts leftover in the rebuild kit. That was mainly due to the fact that I did not no know where they went or where they actually were inside the carb body. Pay attention to what is included in your rebuild kit. Some kits contain parts for more than one model carb which ads to the confusion of what is needed on your carb & what is not. My failure to make notes & understand what the manuals were telling me, was an expensive lesson. Those first carbs, went into the trash can. The rebuilding process is not complicated or complex at all. However it does require you to follow any & all service instructions for satisfactory results. Even if you have done it several times, you should always review the service instructions.

Now that your at a clean work bench & have collected all the necessary tools, vessels and the proper rebuild kit for your carb and the service instructions it's time to start. The very first thing that I do is soak the entire carb in a cleaning fluid. You can buy a carb cleaner from the auto parts store, or use some mineral spirits, kerosene, or a non petroleum based product designed to do the job. Personally, I use a product called Chemtool. It's available at auto parts stores, & Walmart. But let me caution you here. Chemtool will strip the paint right off the carb body & anything else it comes in contact with. It is very aggressive and it could potentially damage non metallic parts within your carb, like rubber gaskets & "O" rings, seals, non metallic valve parts & seats. So before you dunk your carb into a bath of this or any other cleaning agent, it's essential that you know that you can reach & replace any & all non metallic parts within the carb. And because the cleaning agent you may select can strip away paint & finish this does not mean that you can use paint remover to do the cleaning job.

Never use any fine drills, wire, paper clips or other objects to clean out passageway's in the carb. To do so can permanently damage the carb making any rebuild attempt useless. Allow the cleaning agent sufficient time to soften & dislodge any foreign material you believe to be in the carb. Some people suggest using a toothpick inserted into very tiny passageway's. I am not a fan of this either. What are you going to do when the point of that toothpick breaks off deep inside the carburetor? Avoid using any paper towels or rags to dry out a carb. The finest of lint from any of these could be enough to create an additional problem. Best to use your compressor if you have one, adjusted to a low pressure for gentle drying. Or if no compressor is available you can try that canned air they sell to blow dust off computer keyboards & parts. By now you have certainly removed the float from the carb. If you suspect that the float is the cause of your problems, you can easily check it for signs of leakage. Just place it into some very hot water & you will soon see a stream of bubble emitting from it if it should have any leaks. If the float is defective, your choice here is to replace it with a new one if possible, or try your hand at float repair. If your careful, you can usually seal a leak with a spot of lead using your soldiering gun. Your not trying to change this part into a lead covered donut. You just want to seal that tiny pin hole of an air leak so the float will do what it does best...float.

Beyond what I have already said, I can not give specific advice or instructions because all carbs are different while sharing the same basic principals. Pay close attention to the condition of high & low idle needle valves, the inlet valve & seat. The condition of the float & float adjustment within the fuel bowel. And again, work clean & be sure to read & understand the repair instructions & procedures before you start. It's really not difficult at all if you take your time & have the information.

You may not have a choice when it come to rebuild or replace the entire carb. Carburetor's on many of the smaller six, seven, and even ten horsepower engines are just no longer available off the shelf. Occasionally you might find one on a dealers shelf, or possibly the striped down core or body that you can transfer parts to & go from there. And on the chance that you might find an original brand new one available it will likely be a lot more than you are willing to spend for it. It could run as high as two, even three hundred dollars for a new one. And if your going to do that there are at least two things you want to make sure of. Fist, is what you are buying really new & secondly, is it from the original equipment manufacturer & not some look alike clone junk. And if you go into the used market to get one, just keep in mind that you are buying a used carb in an unknown condition. You can't tell how well a carb is just by looking at it. And any used carb you buy will most likely bring you back to square one, which is to rebuild it.

Earlier I said that the carb usually gets the blame for a whole range of ills that it has nothing at all to do with. Now that you have it rebuilt or have found that really great used bargain, you can't wait to put it back on the engine & crank it up. This is the part where you cross all fingers, toes & hope you have been a good person. You start her up, and it's running like a champ...maybe. Or maybe your enthusiasm turns to pure frustration as the same maladies that plagued you before the rebuild are still there.

If your rebuild was a success, congratulations are in order for a job well done. You accomplished two major items. First, you correctly diagnosed the problem as being the carb. And secondly you successfully tore down and rebuilt your carb. Congratulations to you on a job well done! But if your on the other side, the disappointed side, you should just look at it as having eliminated one possibility out of several that are causing you the problem. Chances are that your rebuild efforts were spot on. However further investigation now is needed to find the problem. Keep in mind that something as simple as a faulty fuel tank cap can cause all sorts of problems, not to mention ignition systems & failing engine parts as well.

Sooner or later, you will be faced with this challenge. But if you follow some of the advice I have given here on the basics, I'm sure that you will get the job done. The first carb rebuild is always the most challenging. But if you take the time out to read & understand how carbs work & the common issues they have, you will not have a problem if you decide to rebuild, and for the average price of about fifteen dollars for a rebuild kit, you will have potentially saved as much as three hundred in replacement costs along with the satisfaction that you did it yourself!

Jerry