Carburetor Repair, Maintenance Adjustment How-To Guide
Your Briggs and Stratton carburetor is an integral part of your small engine, so it’s important to keep it running smoothly for the overall health of your lawn mower, snow blower, and other outdoor power equipment. In this article, we’ll give you tips on carburetor maintenance and repair to keep your small engine healthy – so that you can use your power equipment worry-free!
Before starting any carburetor maintenance or repair work, make sure to consult the Briggs Stratton operator’s manual for the machine you will be working on and follow all safety precautions.
Carburetor Maintenance: Cleaning Adjusting Small Engine Carburetors
Performing regular carburetor maintenance is a great way to save yourself money, headaches, and hassle down the road.
Most carburetor problems are caused by a variety of blockages from things like dirt, varnish, and gasoline deposits. It’s easy for the main fuel jet to become blocked, but luckily it’s a pretty easy fix. Regular carburetor maintenance will help you avoid problems in the future.
You can clean the main fuel jet (located in your carburetor’s fuel bowl nut) with carburetor cleaner and compressed air to blow out loosened debris. Carburetor cleaner dissolves deposits in your carburetor and choke, and consequently can reduce your need for maintenance, repair, and downtime, while improve starting for all 2-cycle and 4-cycle engines.
After cleaning the carburetor, another key step for some float-type carburetors is adjusting the idle speed and mixture. Carburetor adjustments can only be made on older, non-EPA regulated carburetors and are generally as follows:
The high-speed (or needle valve)-if equipped-should be turned 1-1/2 turns open from the seat; the idle valve should be turned 1-1/4 turns open from the seat.
Carburetors are now manufactured per EPA emission standards and are not adjustable, they are factory set. First and foremost, don’t tamper or attempt to modify engines designed to meet EPA standards. Not only is it illegal and comes with civil penalties, but it can cause a host of problems. Knowingly disabling an emission control system component will violate the EPA regulations. Installing a part that differs from that originally on an engine that meets EPA standards also may bring penalties for tampering.
Normal maintenance (replacing air filters and spark plugs) and routine servicing such as rebuilding carburetors or replacing jets for high altitude operation are still perfectly acceptable. Full instructions for Overhauling a Briggs and Stratton Carburetor are available in our FAQ section.
Briggs Stratton engine tuneup kits contain new air filters, spark plugs, oil, and easy step-by-step instructions. You can find engine tune-up kits in the Briggs Stratton official parts store online.
Troubleshooting Carburetor Problems in Your Lawn Mower or Small Engine
Sometimes, if your carburetor is gummed up beyond simple maintenance, it may be necessary to rebuild or overhaul it. You can find detailed carburetor repair instructions in our “Overhauling the Carburetor” FAQ article. Carburetor problems are often at the root of many issues with outdoor power equipment. By performing carburetor repair with official Briggs and Stratton parts and cleaner, you can help ensure that your small engine is healthy and running right.
If you have any questions about performing carburetor repair on your small engine, official Briggs and Stratton dealers are here to help. Your local Briggs and Stratton dealer can assist with any small engine repair and maintenance issues you may have. Performing regular carburetor maintenance will save you trouble down the road, so make sure you don’t neglect it. and then you can get back to enjoying using your Briggs Stratton outdoor power equipment!
How Does a Carburetor Work?
Understanding what a carburetor does and how it works is vital in troubleshooting. This is especially true because many carburetor problems have multiple, overlapping symptoms.
The carburetor’s role is to provide the space where gas and air mix. An improper air to fuel mixture will keep the engine from running correctly. An incorrect gas and air mix cause most carburetor problems. Your job is to figure out what is causing the mix to be off.
Mower Speed Problems
If the engine speed does not increase, the speed is unstable, or the engine performs poorly at high speed, then an additional clog to check for is the pilot jet—either its air path or the jet itself are clogged.
Should speed problems happen at low speeds or the idle speed is unstable, then in all likelihood, the pilot jet or its air path is clogged. You will need to check for dirt and clean.
Copyright protected content owner: ReadyToDIY.com and was initially posted on 2020-08-27.
Getting to the Mower’s Carburetor
Before you get started, we recommend you disconnect the spark plug cap. This is to prevent the mower from accidentally starting. Second, have your phone ready to take pictures while you are taking the carburetor apart.
Fix Without Taking the Carburetor Apart
You might get lucky and avoid having to take the carburetor apart. To do so, FOCUS on cleaning out the carburetor idle jet. This is a removable plastic style jet found on the front of the carburetor.
Materials Required
If you can’t get a small engine started, it takes too many pulls to get it going, or it runs poorly, ask yourself this: Did it sit for a long time with gas in it? Like over the winter? If so, your problem is most likely a corroded or gummed-up carburetor. Small engine repair shops earn about 50 percent of their revenue by cleaning or replacing carburetors sidelined by old gas. Look at your lawnmower carburetor next time you sharpen the blades or complete a lawn mower tune-up.
Before you start taking things apart, take a minute to confirm the carburetor is the problem. We’ll show you how to do that, as well as how to clean, rebuild or replace a lawnmower carburetor. Either way, you’ll save about an hour of shop labor (about 80). You can complete the carburetor rebuild project in a single morning, including the time scouting for parts.
How to Find Lawn Mower Carburetor Parts and Prices
Whether you buy parts from a local small engine repair shop or online, you may need all this information:
Trying to find correct replacement carburetor for my Honda mower
I have an older Honda push mower. real old. I believe it may be from the mid/late 90s? Maybe earlier? I received it from my parents about 15 years ago.
Anyway, i’ve cleaned out the carb a number of times over the years and it’s currently not running. Since it’s in bad shape, I wanted to order a new carb but can’t seem to find the correct one.
From the engine code (SHN135U1G1RA) it ‘should’ be the GCV160 carb, but after ordering it I realized that the gcv160 carb’s stud holes are even across, mine are offset.
For age of mower help, this has a plastic deck which I know they stopped doing at some point.
tadawson
Well-Known Member
Have you checked spark, compression, and valve clearance? If not, throwing a carb at it blindly may well be pointless. Not sure on that series, but other Honda engines have the engijemmodel and serial cast into the front. should be easy to cross reference from there, but then again, I don’t see anything that tells me that a proper carb rebuild would not be enough.
kprojects
Forum Newbie
Thanks for the reply. just got the numbers from the block to help determine the correct one. and uploaded the pics above.
Yes, i do have spark, have not checked compression. I don’t have the tools for it. Last time I cleaned the carb however, I noticed that the float pin was missing (or my brother-in-law lost it since he wanted to clean it out while I was doing other things). so I either need to find a float pin or find a new carb. They’re pretty cheap on Amazon, the one I purchased already was 14.99.
kprojects
Forum Newbie
Update: with the help of my local Honda dealer I was able to figure out this is the 16100-ZG9-M12 carb. Hopefully this helps someone out in the future.
tadawson
Well-Known Member
Thanks for the reply. just got the numbers from the block to help determine the correct one. and uploaded the pics above.
Yes, i do have spark, have not checked compression. I don’t have the tools for it. Last time I cleaned the carb however, I noticed that the float pin was missing (or my brother-in-law lost it since he wanted to clean it out while I was doing other things). so I either need to find a float pin or find a new carb. They’re pretty cheap on Amazon, the one I purchased already was 14.99.
You won’t get a Honda carb for that. just dubious quality Chinese ripoffs The original will almost always be better if you can keep it going. You might check with your local equipment shop. they may have a pin in the spare parts pile that you can have.
tadawson
Well-Known Member
Other good news I see! You have the GXV and not the GCV. a far better engine! The GXV is basically the commercial line, whereas the GCV is homeowner grade This should run pretty much forever if cared for. I have a 1989 or so mower with this engine, and other than needing rings, all else was still in spec this spring, 30 years of significant use later!
tadawson
Well-Known Member
Looks like you can buy just the float and pin from Honda as well:
HurstGN
Active Member
For future reference, Honda does have a good parts lookup on their web site: https://peparts.Honda.com/powerequipment#/browse/lm/hrm/hrm215
mechanic mark
Lawn Pro