We get a lot of calls from people that have
"adjusted their carburetors to death",
hoping for that magic moment when it all comes
together and runs perfectly...
here is how you fix what you have adjusted.

 

On most carburetors,
to help find the correct adjustment,
there is a small "L" beside the Idle
mixture screw and "H" beside the
High speed mixture adjustment.

 

 

  Normal adjustment for 2 needle carburetors begins with the L needle. This adjustment controls the fuel flow to the low speed or idle circuit. If the carburetor is too far out of adjustment to run, or has been disassembled, start with turning the L and H all the way in and then open 2 turns on each needle.  Then turn the "TAS" screw or idle speed adjustment in all the way.

When turning any of these screws be careful not to over tighten,
this can cause damage to the carburetor and / or needle.


Now you are ready to begin adjusting.


Start the engine and allow it to warm up for a few minutes. Do not try to adjust the carburetor before the engine warms up as settings change while the engine is warming up. Begin with the L needle, turn the needle in clockwise and listen to the engine as you do so. The engine will speed up to a point then start slowing down again, the point of the highest speed is called optimum. This is at the most efficient point for the engine to run. When you find and set the engine to this point then adjust the TAS or idle speed screw. This screw adjusts the idle speed, you should try to adjust it so the clutch is not engaged or ringing.Note: when the clutch disengages the chain or string will stop moving.Some string trimmers do not have a clutch, so adjust these engines to a steady reliable speed. Once you have adjusted the idle speed it is necessary to recheck the L screw adjustment for the optimum point described above. It may be necessary to repeat these two adjustments several times to get the engine to run correct. The L screw may be opened 1/8  to  1/4  turn from this optimum point to help the engine to accelerate well to full throttle.The high speed adjustment procedure is similar to the "L". Accelerate the engine to full speed and search for the optimum point as described for the L needle. The important part to remember about adjusting the L or H screw is not to let the engine drop much onthe lean side of this point, (screw in) you want to find the highest speed when turning the needle. However going too far past this point may result in engine damage. As with the L adjustment the H needle may be richened a little, but no more then ¼ turn from optimum point.
If your carburetor has no slots for a screwdriver,
as in the picture, it is adjustable "only" (see note below)
 with a special screwdriver available from the original
equipment manufacturer.
Most manufacturers only sell these to dealers.

SHADE TREE NOTE:

 (and you didn't hear it from me

A small dab of "crazy glue" on a small nail head can often be fused to the tip of the adjustment screw to give you enough leverage for adjustment. Clip the nail off with side cutters when finished.

 

Still no luck? There is a good chance that either you have poor quality fuel, or a defective (read "Bad") Carburetor and further steps are needed. Replacing the gaskets and a thorough cleaning (putting a" kit" in it) is the next logical step, but still may not fix the carburetor.

 

Carburetors with white scaly metal (white rust)
 inside don't usually heal with a kit and need replaced.

 

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Not looking at the right stuff? Choose a brand from the menu above.
AGRI-FAB---Makers of fine lawn and garden tractor attachments lawn mowers
AMF---There are still a few parts available for these units through Murray
AMERICAN YARD PRODUCTS---Makers of Craftsman, Wizard, Poulan, Weed Eater
ARIENS---Currently we are only supplying Aftermarket Parts for this brand.
ATLAS---Built for the Canadian market by MTD
AYP---Manufacturers of Craftsman, Wizard, Poulan, Poulan Pro , Weedeater and more
BLUEBIRD---A few aftermarket items available
BOBCAT--- Many common belts and blades available for Bobcat Mowers
BRIGGS & STRATTON---The most popular engine we have all the parts you need!
BOLENS---One of MTD's product line. Sold at Lowe's and Home Depot
BUNTON---Aftermarket only for these mowers - no parts lookups
CARLISLE---Carlisle tires are the most popular tire used in the Outdoor Power Industry
CHAMPION SPARK PLUGS--- Popular Spark Plugs used In Outdoor Power Equipment
CLINTON---Aftermarket only for these - no parts lookups
CLUB CAR---Aftermarket only for these - no parts lookups
CRAFTSMAN--- Americas most popular brand of power equipment.
CUB CADET---We carry the Cub Cadet residential line. Not all Cub parts will be available
DANA--- Transmissions and Transaxles popular in the lawn and garden market
DIXIE CHOPPER---Aftermarket only for these - no parts lookups
DIXON---Aftermarket only for these - no parts lookups
DOLMAR---Chain Saws, String Trimmers, Demolition saws, hedge trimmers and more
DYNAMARK---Purchased by Murray several years ago, some parts available for these
ECHO---Aftermarket only for these - no parts lookups
ELECTROLUX---/ American Yard Products, some AYP equipment with EHP model.
ENCORE---Aftermarket only for these - no parts lookups
EXMARK---Aftermarket only for these - no parts lookups
EZGATE--- Easily raise your trailers tailgate with this simple addition.
FERRIS---Aftermarket only for these - no parts lookups
FHP---Another of the brand monacres for American Yard Products
FOOTE---Dana Foot and Spicer are - Outdoor Power Equipment Division Only
FRIGIDAIR HOME Products--- American Yard Products built
GENERAC---"Old Generac" and "new Generac" combined into this database
GILSON---Aftermarket only for these - no parts lookups
GOODALL---Aftermarket only for these - no parts lookups
GRASS HOPPER---Aftermarket only for these - no parts lookups
GRAVELY---Aftermarket only for these
GREAT DANE---Aftermarket only for these - no parts lookups
GREEN MACHINE---Aftermarket only for these - no parts lookups
HAHN---Aftermarket only for these - no parts lookups
HONDA--- (Power Equipment & Engines) Full line of Honda power equipment Parts
HOMELITE
HUSQVARNA LAWN MOWER PARTS--- Mowers, Tillers, Snow blowers
HUSQVARNA HAND HELD---Chain Saws, Trimmers, Blowers and such
HUSKEE---Another buyout company of MTD, many parts available.
Hydro-Gear Parts and Replacement Units--- The most popular pumps and motors
No "I" Brands
JACOBSEN---Some parts still available as Homelite Parts
JOHN DEERE---Aftermarket only for Deere - Many belts blades,switches and more
KAWASAKI--- We have all of the parts for these quality Kawasaki engines
KEES---Aftermarket only for these - no parts lookups
K-GRO---Another American Yard Products Product
KOHLER--- Full line of OEM and Aftermarket parts for these engines
KUBOTA---Many Aftermarket parts available for Kubota. - no parts lookups
LAWN BOY---Aftermarket only for these - no parts lookups
LAWN CHIEF---Produced by MTD. Thousands of parts available for Lawn Chief Models
LAUSON---Lauson engines and engine parts
LCT--- LCT engines and engine parts
MCCULLOCH---Chainsaws / Handheld equip. Aftermarket only for these
MCCULLOCH---Lawn Mowers produced by AYP
MONTGOMERY WARD--- Most montgomery Ward mowers were built by MTD
MTD---They're everywhere they're everywhere! MTD parts inside.
MURRAY---In its day, Americas most popular mower. Many parts still available
Oregon--- Chain saw bars, chains, and clutches. Oregon Lawn mower parts are also included here.
PEERLESS---Most parts and transaxles are still available
POULAN MOWER AND TILLER PARTS---AYP Poulan branded equipment here.
POULAN  SAW / TRIMMER / BLOWER PARTS--- Handheld units
POULAN-PRO  MOWER AND TILLER PARTS---AYP built and supported.
POULAN-PRO  SAW / TRIMMER PARTS---Handheld units
No "Q" Brands
RALLY PARTS--- Most parts are still available for Rally equipment
RIDGID Power Tools--- Bought by TTI, Most parts are still in production
ROPER---American Yard Products built Outdoor Power Equipment carry the Roper name.
RYOBI Outdoor Power Handheld--- All trimmers EXCEPT Yellow Shaft Models.
RYOBI Lawn Mowers---Manufactured for Ryobi by its parent company MTD
RYOBI Hand Tools---Power tools by Ryobi, Brushes, cases, cords and everything!
SCOTTS---Purchased by Murray, many parts available No parts for John Deere built Scott's
SENTRY--- Another Murray branded line of mowers and equipment
SEARS--- Craftsman branded equipment
SNAPPER --- ForestGump Shops Here! We carry most Snapper parts
SPICER---Transaxles, Differentials, and Transmissions By Foote
STANLEY---Stanley by Murray. Many parts still available for Stanley Mowers
STENS---Cross reference your Stens numbers into Rotary Parts
STIHL---Aftermarket parts only for Stihl saws and equipment.
TECUMSEH--- Thousands of parts still available for this discontinued brand of engines!
TILLOTSON---Tillotson Carburetors, Carb Kits, Floats, Gaskets and more.
TORO---Aftermarket parts only for Toro at this time.
TROY BILT--- MTD manufactures all of the parts for these Mowers and Tiller.
No "U" Brands
No "V" Brands
WALBRO--- Walbro Carburetors, Carburetor Kits, and Replacement Parts
WEED EATER HAND HELD--- String Trimmers, Blowers, Chainsaws
WEEDEATER MOWERS & TILLERS--- OEM AYP Parts Weedeater equipment here
WHEEL HORSE--- We carry Rotary brand Aftermarket parts for these
WHITE OUTDOOR PRODUCTS--- Division of MTD, we carry the full line of White Parts
WIZARD--- Wizard Power Equipment Parts and Accessories. (Power equipment only)
No "X" Brands
YARD MACHINES--- YardMachine mower parts keep your Yard Machine in top shape.
YARDMAN--- MTD built Yard Man we have the parts you need to repair them.
YARD KING--- Many parts available. Belts, blades, wheels, pulleys, spindles and more
YAZOO--- Aftermarket Yazoo Parts only

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