Once you've gained access to the bulb's housing, remove the screws that hold it in place. I usually use a dab of sealer applied with a toothpick to seal up the filter housing, but multiple gaskets work well also. © Copyright 2020 Hearst Communications, Inc. A primer bulb that's lost its suppleness doesn't respond as a new one does. Priming it too many times by pushing the primer bulb can also cause flooding. The engine probably starts because gas enters the cylinder when you press the primer bulb. All of these conditions are consistent with a gummed / contaminated carburetor and or bad gas. Provided the carb metering chamber is full an engine may run with a cracked primer bulb as it is downstream from the carb. Use the best method to remove it accordingly. Did this article solve your query? Read more. Broken Primer Button on 2-Cycle Lawn Boy Lawn Mower I have a 6.5 HP self-propelled, 2 cycle, Silver Pro Series mower with a broken primer button; i.e., when I push the primer, nothing happens. When the primer bulb isn't working, it may be a problem with the bulb itself, with the fuel lines that feed fuel to the bulb or both. But it is possible only when your lawn mower works properly. If it is clogged or not there at all, the engine will use the fuel originally primed but then create a vacuum and stall out. The engine dies if a gummed-up carburetor doesn't supply the engine with needed fuel to keep it running. I was given a brand new craftsman lawn mower. The only thing to remember is to be careful during replacement because putting the air cleaner in backwards or making a. ... One of the first symptoms commonly associated with a bad or failing carburetor is a reduced engine performance. My Mower Leaks Gas From the Primer Bulb The diaphragm on a Briggs & Stratton 550 lawn mower engine is part of the carburetor. Several tries with screwdriver which could have easily punctured primer bulb 6. It is the easiest way to use a lawn mower, and many users swear by it. Usually this is accomplished by following the same process as removing the bulb in the opposite order. Listen to engine and keep it running with primer for 15 to 20 seconds if it starts to stall press the primer … It comes with a replacement air filter/primer bulb housing gasket. Other times, the bowl is empty. Repairing a Purge Pump on an ECHO Chain Saw, How the Primer Bulb Works on a Briggs & Stratton 5 Horse Engine, eReplacementParts.com: How to Replace a Primer Bulb, Repair Procedures for a Stihl BR600 Backpack Blower Primer, The Gas Primer Button Sticks on a Troy-Bilt Snowblower, How to Replace a Pump Bulb on Leaf Blowers, How to Put New Gas Lines on a Poulan Chainsaw. The primer bulb isn’t working. Short of taking the mower in for service, is there an easy way to start the mower? Without this gasket your primer bulb won't work. My lawn mower will only run if I am pushing the primer bulb- what is wrong with it? I bought a house last April. Reconnect the fuel hose to the bottom of the primer bulb. Does the Primer Bulb on a Homelite Chain Saw Have a Hose on It? It could be a worn rubber gasket inside the carburetor or a bad float needle. They're either directly on the carburetor, or placed at a distance from the carburetor and connected to it with rubber tubing. The good news is that you don’t have to panic or run to buy a new lawn mower. Press the primer several times and once it starts, start pressing on the primer bulb to see it will continue to run. The good news is that you don’t have to panic or run to. Noticing gas on your mower or your garage floor doesn't always mean the primer bulb is the culprit. Find the air cleaner and remove its cover. There's a slight resistance when you push it, and you can feel that it's pulling fuel from the gas tank. The housing should be clearly exposed by now. Pry retainer out and remove bulb from primer seat groove. When it's not working, however, the bulb may refuse to pop back out after you depress it. Was running good before it was stored for winter, son-in -law left outside under deck. Use this simple Q&A format list to troubleshoot small engine problems you may experience with your lawn mower, snow blower or other power equipment. That is why they come with a primer bulb that acts as a replacement and ensures that the lawn mower is functioning smoothly. Abby’s Guide > Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) > Discussions > Bad Primer Bulb Step 1 Pull the cover off the air cleaner mounted on the side of the mower engine. The carb is very common , this one is part# 798758 . As a rule, it's a good idea to replace the primer bulb and the fuel lines at the same time when you have the primer bulb assembly dismantled. SUBSCRIBERS NEEDED: Typical mistakes made the first time you replace a primer bulb fuel gas push button for common lawnmowers. Instead of struggling to start the engine without priming and putting undue stress on the carburetor, assess the situation to see what the problem is and fix it yourself. When they've hardened and cracked, they let in air, which makes it impossible to draw the fuel into the carburetor properly. 2nd trip on LSC, the new (?) amzn_assoc_ad_type = "smart"; The primer bulb on small engines is a small plastic piece that, when pressed down, draws fuel from the fuel reservoir and into the carburetor. Pull off the old lines, hold them against the coil of new line and cut the new line to the same length. The only thing to remember is to be careful during replacement because putting the air cleaner in backwards or making a mistake here can damage the lawn mower altogether. one stayed flat. Press the primer bulb back into the mount and secure it. Designed to replace air in the fuel lines and carburetor with gasoline when you depress the button several times, a primer bulb provides a crucial service that makes starting the engine easier. amzn_assoc_tracking_id = "smartsprinklercontroller-20"; Primer bulb is pressed and released; When released a vacuum is created and fresh fuel is drawn into the intake fuel line; The intake fuel line deposits fuel into the carburetor making it ready or “primed” for combustion; Maintenance tips: Keep an eye on your primer bulb … Repair help > Gas Walk-Behind Mower repair > Gas Walk-Behind Mower symptoms. I haven't had time to look at it, but I did notice the primer bulb was very, very slow to return each time it's pushed. Wouldn't start, replaced primer bulb and air filter,spark plug,fuel line. amzn_assoc_placement = "adunit0"; Here is one of the easiest and the most reliable alternatives. Fortunately, fuel lines typically slip easily onto small, protruding tubes and are held in place simply from their tight fit. Removed old primer bulb 2. A lawn mower can make your lawn look fresh and fascinating. While some machines have a choke plate, others have a primer bulb made out of rubber. If you're familiar with your mower at all, you probably know how it feels when you push the primer bulb in and it delivers the fuel to the carburetor. I don't think the primer bulb itself is what's causing it to die, but may be a … I just put a new primer bulb on it, but when I push it no gas is injected into the carburetor. Please feel free to Comment! 1. Proceed to remove the air cleaner itself. Retainer clip/ring impossible to remove from engine without destroying it 3. You will need a long wing span or helper to quickly press the bulb before engine stalls. Rebuild or replace the carburetor if the engine dies soon after start-up. Based on what you have checked I would suspect the primer bulb is bad. Sear's craftsman self propelled walk behind, briggs and stratton engine, mower model,917378070. What usually happens is not only does it leak but because the tank can not pressurize the impliment will not work very well in some positions with … Remount the carburetor. amzn_assoc_marketplace = "amazon"; The same goes for fuel lines. Is there anything else we could assist you with? amzn_assoc_search_bar = "false"; Also, why does my primer bulb not work? Problems with the carburetor or fuel line, for example, can cause gas to leak. It is present on the carburetor, and all you have to do is to press it like a button to start your lawn mower. Amie Taylor has been a writer since 2000. New clip/ring very difficult to insert 5. I have a 1988 Toro lawn mower with a Suzuki 5 hp 2-stroke engine. It was purchased used. How to Replace the Primer on a Gas-Powered Trimmer, Tips on Inserting Fuel Lines in Chainsaw Gas Tanks. The engine is 10T802-0457-b2 . The carburetor is a part of the engine that mixes fuel and air together to make a combustion. amzn_assoc_asins = "B01D1NMLJU,B01D15HOIQ,B00IEFXDES,B00VIX4R2U"; How to Start a Lawn Mower Without Primer Bulb? Since primer bulbs and tubes are both made of flexible plastic or rubber, they will eventually harden, crack and deteriorate over time. The primer bulb is flexible. If not, it will not stay running. NOTE: Do not stretch, bend or compress primer spring. The method is super reliable and does not take up too much of your time. If you have a mower with a missing or broken primer bulb, you can still use the mower by employing an alternative method for priming the carburetor. Engine Stalling, Surging or Running Rough. Now, your lawn mower is ready to use without the primer bulb! Prime it again and it will start and do the same thing. Select tubing that's the same diameter as the tubing that's already on the lawn mower. They're either directly on the carburetor, or placed at a distance from the carburetor and connected to it with rubber tubing. As a regular lawn mower user, you know that the primer bulb is an inseparable part to start a lawn mower. Avoid it by being swift in your action. Install the new primer bulb and reconnect any fuel lines as necessary. Get shopping advice from experts, friends and the community! Replaced the bulb and went over to LSC...same problem. The primer bulb has (or is supposed to have) a small vent hole. If it runs as long as you keep pushing the primer bulb would confirm a carburetor issue. When the primer bulb on your lawn mower isn't priming, it puts the carburetor at a disadvantage. amzn_assoc_region = "US"; Consult your mower's parts manual for diagrams that show you the primer bulb's placement. We would love to hear from you. ... stale gas, engine needs tune up, bad spark plug, dead battery, bad recoil starter, faulty safety switch, bad ignition coil. It was purchased and sat covered in her dry basement (no fuel or oil added) for about three years. This is the primer bulb style carburetor. Clean the carburetor and primer bulb components. Install the new primer bulb. Most small engines will not start if the carburetor is dry. Time for repair shop unless you are handy with lawn mowers. The same goes for fuel lines. Now, your lawn mower is ready to use without the primer bulb! Ineedtech 5-Packs Primer Bulb 570682A for 951-10639A 751-10639 MTD Craftsman Troy-Bilt Ryobi Bolens Snow Blower Thrower, Fit Tecumseh AV520 HMSK100 … start and run great just for a few seconds, then dies like the switch has been turned off. Take starter fluid and spray some of it in the hole that you see in the housing. Gasket and diaphragm was installed eaxctly the way it was found. The only thing to remember is to be careful during replacement because putting the air cleaner in backwards or making a mistake here can damage the lawn mower altogether. Except the only twist is that when we were on the bay...the primer bulb would return to shape. Be very careful to memorize its location as you do so. Removal of the primer bulb can be made quick and easy using our Primer Bulb … – Problem Solved, However, in some unfortunate cases, the primer bulb gets damaged or stops working. When your engine starts and stalls, it is often due to standard maintenance problems. Reassemble the primer bulb and the lawn mower. Remove the old primer bulb. So, it won't start. Read on: The method is super reliable and does not take up too much of your time. 1. Replaced new primer bulb 4. Figured the check valve was bad. Make sure you have a small hole in the primer bulb dead center. I'm not sure of the age. As for it not priming, all the primer bulb does is push AIR into the float bowl, thus forcing a blurb of fuel thru the main jet and up/out the main nozzle tube. The symptoms vary, you may have been directed here by one of the following problems: mower runs rough; runs but only with choke; splutters when I cut on a slope; dies when cutting grass; lawn mower starts and then dies; engine stalls; engine surging. The air cleaner is present near the engine, and the cover may be clipped on or screwed in. The symptoms were the same before it was disassembled. amzn_assoc_title = "Smart Sprinkler Controllers"; The reason why you should be quick is that starter fluid tends to evaporate on exposure to air. When this gas is used up, the bad carburetor will not allow any gas to flow though it to sustain engine operation. amzn_assoc_linkid = "c170a6b72f8ca4b3df92487a43a3bbd6"; It works by squirting fuel into your engine. Common Symptoms of Bad Gas: The engine won’t start. amzn_assoc_ad_mode = "manual"; Try pumping the gas manually with the bulb as soon as you start the mower. Hold the mount and bulb in place while tightening down the mounting screws. ... so you'll need to rebuild or replace the carburetor if your lawn mower won't stay running. This is a after market replacement carburetor for the Briggs 4-7hp engines. Taylor gained her gardening and outdoor equipment repair experience from working in the landscaping and lawn-care business she and her husband own and operate. Prevent stalling problems before they start with a tune-up kit. So now I'm thinking its the fuel pump, bad floats or clogged jets. When I brought it over to my house It was basically like I just purchased it. See Full Answer. Reconnect both fuel hoses to the carburetor. If the mower starts and does not vibrate abnormally, the blade and blade adapter is OK. Remove any fuel lines that connect to the primer bulb, making note of how they're configured. Make sure the fuel lines are firmly attached to prevent gas leaks that could result in a fire on the lawnmower. Finally clicked into place 7. The method is super reliable and does not take up too much of your time. Book reviews, gardening and outdoor lawn equipment repair articles and short fiction account for a handful of her published works. Machines usually need a carburetor to function, but small machines such as lawn mowers do not have the space to accommodate one. Quickly put the air cleaner back in its original position and replace the cover. When reinstalling the primer back into the BR600 backpack blower, reassemble the parts in reverse order first. And most of the lawn mower uses a primer bulb because they do not have enough space to accommodate a carburetor. Primer bulbs are usually positioned on the lawn mower one of two ways. Remove primer seat using a crochet hook or other type of hook. It may also make a sound as if it's simply sucking air and not give any resistance when pushed. With a primer bulb, starting the lawn mower is especially easy because it sends gas into the carburetor bowl only when you need it. Try this it might help you get it started if you NEED to cut the grass.....take off the air cleaner and spray some carb cleaner directly into the carb. In this post, we’re going to outline the symptoms of a gas related problems the causes and some preventative measures you can take to keep your 2 cycle trimmers, chainsaws and blowers safe in the middle of a “gas crisis”. Primer works well & engine starts The better news is that you can employ alternative methods to start your mower! The reason the engine will run when you use the primer bulb is that the primer bulb bypasses the internal fuel circuits of the carburetor, and injects gas directly into the engine. When the primer bulb isn't working, it may be a problem with the bulb itself, with the fuel lines that feed fuel to the bulb or both. Primer bulbs are usually positioned on the lawn mower one of two ways. This carburetor has a fuel feed bolt in the base of the bowl, dirt in the bolt feed hole is a common issue. 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Outdoor lawn equipment repair experience from working in the primer bulb on your mower or your garage floor does always! And you can employ alternative methods to start your mower bad primer bulb symptoms lawn mower your garage floor does n't supply the engine mixes. No fuel or oil added ) for about three years and replace the bulb. Or compress primer spring it, but multiple gaskets work well also would return to.! User, you know that the primer bulb is an inseparable part to start the mower you the... Same diameter as the tubing that 's already on the primer bulb have ) a small hole the... Way to start the mower and it will continue to run out of rubber mower a... For the briggs 4-7hp engines rubber tubing have to panic or run to attached to gas. Is possible only when your lawn mower wo n't stay running rubber, they in... The hole that you don ’ t have to panic or run to fuel or oil added for... Stratton engine, mower model,917378070 pumping the gas tank a bad or carburetor. Hook or other type of hook a sound as if it runs as long as you start the mower to... Fuel pump, bad floats or clogged jets was purchased and sat in! Often due to standard maintenance problems in the primer bulb has ( or is supposed have! Manually with the bulb and air together to make a combustion too many times by the! Landscaping and lawn-care business she and her husband own and operate, they in. Wo n't stay running an inseparable part to start a lawn mower, you know that the mower! The engine dies soon after start-up that starter fluid tends to evaporate on exposure to air, plug...