My TS 420 will not prime. I installed a new primer bulb and still no gas. Any ideas? Thanks.

Jeremy Reddick

• 1902 Answers

SOURCE: 323L Husqvarna trimmer

This sounds like the carb needs to be adjusted like it is letting to much fuel into the cylinder. There is supposed to be fuel and air mixture in the cylinder to make it fire. If there is to much fuel what will happen is that it will just build up in there and the air wont get hot enough as it compresses to start the engine.

Posted on May 21, 2009

SOURCE: primer bulb won't prime

it sounds like the filter on the fule line is cloged try to remove the filter and then try to prime the trimmer. it it does you need to replace the filter. just about any filter that will fit will do.

Posted on Jun 10, 2009

SOURCE: PRIMER BULB WONT PRIME

I would recheck the carburetor to make sure you put the diaphragms next to the carburetor and not the gaskets.
Please if it is not priming you may have the fuel lines hooked up wrong. Also check the fuel cap to make sure the vent assembly is there. If the tank is not venting, the tank will get a vacuum in it not allowing fuel to flow.
HTH
Good Day.

Posted on Nov 11, 2009

SOURCE: Walbro WT891 carb on a

Who connected these hoses? the normal routing for a machine with a primer is like this, the fuel hose from the tank with the filter on the end goes to the carb fuel inlet nozzel ( not to the primer ) nearest to the pump cover ( cover on carb held with one screw ) the pipe from the metering side of the carb connects to the shorter nozzel on the primer bulb ( suction side ), the longer nozzel on the primer ( pressure side ) connects to the pipe going back to the tank, just remember the primer pulls fuel from the carb,into the bulb, and pushes it back into the tank, it is not actually a primer it is a purge. because it is connected this way it is impossible to flood the engine no matter how many times the bulb is pressed.
Let me know if it starts and runs.

Posted on Jan 31, 2011

SOURCE: Ryobi 410 mini tiller w/Walbro WT149A primer bulb won't prime. New bulb, new fuel lines, hooked up right, carb cleaned. Been sitting for several years.Runs when fuel is pumped into the fuel inlet.

hello sir, my machine will only start when pumping primmer bulb or squirting fluid in the carburetor than stops. the fuel line has broken off, in most small carburetors this is a ongoing problem.old fuel will crystallize when left in tank for a long time.plugging up ports, fuel lines, small screen in carburetor.fuel lines will dissolve clogging carb.this is why it will run when the choke is on creating a vacuum to where there is fuel forced in the carb to rum,also the gas will evaporate leaving the oil behind clogging up carb.the thing to do is remove carb. and clean out,replacing gaskets or fuel line if necessary.use carb cleaner to clean out carb.make sure to make note where fuel line go.the fuel filter broke off of fuel line letting debris get in carb plugging it up.the muffler is known to clog up a lot on these machines where they want run. the compression should be 60 to 120 lbs any thing below 60 is junk. when adjusting the carb screws turn in all the way than turnout 1 1/4 turns turn in slow until machine runs also you need to check for spark by removing plug and grounding against engine to check spark, ok.a new spark plug would be a good ideal too , if you are going to make these repairs use new fuel line and filter,hope this helps,any comments welcome,thank you, !!

Posted on Feb 22, 2012