How to Diagnose and Repair Carburetor Problems by Larry Carley copyright 2019 AA1Car.com. DIAPHRAGM CARBURETOR DIAGNOSTIC This documentation can be used as a guide how to inspect and diagnose failure associated with the diaphragm carburetor used on the Honda GX100. Engine will not start; Engine will not idle; Engine lacks power at high speed; Carburetor floods; Idle speed is excessive; Check diaphragm for cracks or distortion and check nylon check ball for function if available. Performance problem. Shows symptoms and solutions to fix the Zama Carburetor, The E-Myth Revisited: Why Most Small Businesses Don't Work and, Secrets of the Millionaire Mind: Mastering the Inner Game of Wealth, Shoe Dog: A Memoir by the Creator of Nike, The 5 Love Languages: The Secret to Love that Lasts, No More Mr. Nice Guy: A Proven Plan for Getting What You Want in Love, Sex and Life, Midnight in Chernobyl: The Story of the World's Greatest Nuclear Disaster, 0% found this document useful, Mark this document as useful, 0% found this document not useful, Mark this document as not useful, Save Zama Carburetor Troubleshooting Charts For Later. carburetor troubleshooting table of contents – page 1 of 1 introduction how to identify a tecumseh carburetor series 1 (2-7 h.p.) In this guide I'll cover the main problems with small engine carburetors and the solutions. CARBURETOR DISASSEMBLY Before disassembling the carburetor for inspection, a well-illuminated, clean surface is essential to good carburetor repairing. Keihin carburetors are designed to be used with normal pump gasoline. If you ar… TROUBLE SHOOTING DIAPHRAGM CARBURETOR PROBLEMS. WALBRO WTA, WT, AND TILLOTSON HU DIAPHRAGM PUMP CARBURETORS. Tecumseh carburetors are identified by a manufacturing number and date code stamped on the carburetor as illustrated (diag. It offers a 90 degree air inlet to pro-vide low overhead clearance, and is available with several Air Horn and throttle body options. After ruling out any engine related performance problems use chart 2 to help determine the fault for the carburetors malfunction. CWM © 2020 Powered By GlobalData Ecommerce Solutions. Small Engine Carburetor Troubleshooting. Metering Lever 9. If your carburetor is leaking gas, the float bowl gasket may be worn out. Click here for a link to the "Carburetor Assembly Look-Up. Metering Diaphragm Cover 3. Inspect possible fault • • • • • • • • • • • Metering Lever Pin 7. The vacuum leak will prevent the slide from opening fully, and it will artificially limit the operating range of the carburetor. Inlet Valve Needle 8. Inspect possible fault. My accelerator pump diaphragm leaks around the housing. A small flat-head screwdriver – to remove the retaining screw. It is available as a complete fuel system including carburetor, integral fuel pump and filter for two stroke cycle engines or as a carburetor … When servicing carburetors, use the engine model and Walbro / Tillotson diaphragm carburetors operate exactly the same way where a diaphragm operated fuel pump (Impulse type) and a diaphragm & needle meter system. a ac st O.T. Small engine carburetors don't handle bad or dirty gas very well, if you own a small engine, you'll encounter carburetor problems at some point. Carter YF 1 Barrel Carburetor Troubleshooting. Reassemble the carburetor, making sure all parts are clean and that none are damaged. More or less pump stroke is adjusted by attaching the pump rod to one of the holes in the throttle pump lever. Tillotson has developed the HR Series Diaphragm carburetor for engines with a displacement of from 12 to 25 cubic inches per cylinder. We will assume you have confirmed the following items and inspected all the possible faults as specified in chart 1. Engine Air leaks / bolts loose / gaskets damaged. Screw off the bottom of the carburetor to reveal the rubber gasket and diaphragm. TROUBLE SHOOTING DIAPHRAGM CARBURETOR PROBLEMS Engine problems that can be mistaken for carburetor problems. As the hole enlarges, the engine will eventually do no more than idle. Step 4. Diaphragm Gasket 5. Carburetor troubleshooting is simple once the basic principles are known. Common things to check that can effect carburetor performance. Dust Seal 12. The Walbro and Tillotson diaphragm pump carburetors operate similarly by using a diaphragm impulse fuel pump and a diaphragm/needle metering system. TROUBLESHOOTING. These sometimes become warped and need to be made flat again. When you squash it in, it should bounce right back and have good spring. Answer - You can use our Product Look Up Search feature to view a parts list of the carburetor model, which includes the rebuild kit part number and breakdown. You will need to have several basic tools for this repair: 1. 2. Diaphragm 4. Engine hunts (at idle or high speed) Engine lacks power at high speed They are numbered from 1-4 starting at the bottom. Diaphragm Cover Screw 2. Remove the carburettor from the car to clean it. This acts in a similar way to a toilet cistern and ball cock valve, ensuring there is always a full reservoir of fuel at a … You should observe a healthy squirt of fuel from the pump jet. Spray carburetor cleaner on the jets and needle valves to help free them of dirt. If you notice gas dripping from your carb, or if the idle gets unreliable, replace the needle valve and adjust the lever even with (or slightly below) the carb housing if you don’t have a gauge. This section describes the procedure recommended to properly diagnose a Zama diaphragm carburetor problem on a two-cycle engine. Keep it upright to avoid spilling petrol, then empty it safely. The carburetor itself is a fuel pumper in the way that it draws fuel from the fuel tank with no external pump and in any carb/tank position. Fuels that contain over 10% alcohol content may damage parts in the carburetors. The diaphragm is commonly the problem and the first thing to replace – it’s sometimes hard to tell whether it’s damaged (tell tale signs have been shown in video to make this easier). Welch Plug 11. Jetting Your Slide Valve Carburetor (PDF) Jetting Your CDKII Diaphragm Carburetor (PDF) Jet List (PDF) Slide Chart (PDF) If the diagnoses result in action that involves repair of the carburetor then follow the disassembly and service instructions on the subsequent pages. In most ways, a diaphragm carburetor works exactly like other carburetors but with a unique mechanism for maintaining fuel levels inside the fuel chamber. Some spray carburetor cleaner and a few rags or paper towels. A small Phillips screwdriver or better yet, a Pozidriv bit – to remove the four screws holding the diaphragm to the piston body. Engine problems that can be mistaken for carburetor problems. Checking carburetor slide diaphragms for problems - YouTube 1). Low speed and high-speed enrichment needles are adjusted to manufacturers recommendations. ... • If the carburetor is equipped with a pressed in nozzle assembly, do not attempt to remove it unless you are certain it is malfunctioning. Walbro WTA, WT, and Tillotson HU Diaphragm Pump Carburetors – Troubleshooting Guide. One corner of the diaphragm has a spring. • Inspect pump diaphragm, replace if diaphragm shows any signs of wear or curling. Heat the housing with some pressure from a … The manual pumper is required to prime the carburetor before the engine will start. yIf the carburetor is a strainer and C-ring type, install the strainer and C-ring. An advantage of the diaphragm carburetor over the float style is that the diaphragm carburetor will allow the engine to operate at a greater degree of tiltability. Engine compression and crankcase vacuum are to manufacturers specs. • Remove pump diaphragm and pump gasket. All manual are in pdf format - Chainsaw Carburetors & Trimmer and Blower Carburetors. 5. Float Carb Rebuild. 4. The rubber diaphragm may become holed - and even a tiny hole causes loss of engine power. Metering Lever Screw 6. Many suspected carburetion issues are actually caused by faults within the ignition system, making this the first place to look before making any carburetor adjustments. This may prevent the carburetor from functioning properly. If it is necessary to remove, carefully press it out with steel rod or punch Page 19 TECUMSEH CARBURETOR 1. SU & Zenith-Stromberg Fuel and Carburetor Symptoms & Diagnosis Before adjusting the carburetors, verify that the following items have been checked for proper operation. The most common problems associated with these carburetors will be found in these two areas. The float diaphragm degrades and reap havoc on tuning, especially the low end and idle. TROUBLE SHOOTING DIAPHRAGM CARBURETOR PROBLEMS, Plugged / restricted fuel pump pulse passage, Air filter restricted (dirt / fuel) • • • • Fuel line leakage • • • • • • Piston/cylinder damaged or scuffed • • • • • Restricted muffler • • • • •, Dirt in fuel system / old fuel • • • • • •, Fuel tank vent open or restricted • • • • • • Faulty ignition switch / module • • • • • Throttle linkage binding • • • • High engine friction or load • • • • •. Carburetor floods; Check float shaft for wear and float for leaks or dents.