Is it an adjustable main jet type? Absolutely NO wear on float tang or needle? Absolutly perfectly clean? Air will blow thru all passages? As mentioned, if you blow thru carb with air hose or using vacume cleaner on ex side does it pull up fuel easily? How worn are these mowers? Consider the fact they may be worn out to the point that they don't have enough vacume to pull fuel when pull starting, but enough when it's spinning at 1,000 rpm.
lawn mower help?!?!?!!
- Thread starter Quadrider10
- Start date
i guess. its weird that it the same thing would happen to both carbs..... ill try tomorrow.
they both have good compression. the one is old, and the other is new. the guy still has the box to it. ill try the vacume thing tomorrow. and yes everything is spotless, and neeedle moves freely.
What brand of engine are you working on? Briggs and Stratton? Honda? Tecumseh?
You've got a blocked main jet in the carburetor. As long as you have fuel coming into the bowl and it is not pouring out due to a damaged needle or mis-adjusted float, you can rule out a needle or float problem.
Briggs and Stratton Intek and Quantum engines use plastic floats anyways, where the float height is not adjustable.
Take the bolt out which holds the float bowl onto the carburetor. Study the bolt carefully. You have one or two large fuel feed holes in the side of the bolt, as well as a hole in the top of the bolt. All three holes must be clean and free of obsturctions for the engine to run. The main jet on most lawnmower carburetors is made into the float bowl retaining bolt.
Bolt passages clean and still no-start? Check the emulsion tube in the carburetor. It is located in the 'tower' in the center of the carburetor, where the bowl bolt screws in. Ream it out with a piece of wire. The wire must be able to pass all the way into the venturi for the engine to run.
Also, if you're working on a Honda engine (GXV or GCV series), or Kawasaki engine (FC or FJ series) the main jet is located in the 'tower' in the center of the carburetor, not the bowl bolt. It must be unscrewed and removed. The emulsion tube can then be knocked out and cleaned once the jet is gone. Tecumseh and Briggs and Stratton engines have pressed-in emulsion tubes which cannot be removed to be cleaned.
Hang in there; you'll get it figured out. I fix lawnmowers for a living (certified Kohler Master Service Technician), so I have plenty of practice fixing these sometimes-frustrating machines.
Post a pic of your carburetor. It'll help us figure out what you're dealing with.
You've got a blocked main jet in the carburetor. As long as you have fuel coming into the bowl and it is not pouring out due to a damaged needle or mis-adjusted float, you can rule out a needle or float problem.
Briggs and Stratton Intek and Quantum engines use plastic floats anyways, where the float height is not adjustable.
Take the bolt out which holds the float bowl onto the carburetor. Study the bolt carefully. You have one or two large fuel feed holes in the side of the bolt, as well as a hole in the top of the bolt. All three holes must be clean and free of obsturctions for the engine to run. The main jet on most lawnmower carburetors is made into the float bowl retaining bolt.
Bolt passages clean and still no-start? Check the emulsion tube in the carburetor. It is located in the 'tower' in the center of the carburetor, where the bowl bolt screws in. Ream it out with a piece of wire. The wire must be able to pass all the way into the venturi for the engine to run.
Also, if you're working on a Honda engine (GXV or GCV series), or Kawasaki engine (FC or FJ series) the main jet is located in the 'tower' in the center of the carburetor, not the bowl bolt. It must be unscrewed and removed. The emulsion tube can then be knocked out and cleaned once the jet is gone. Tecumseh and Briggs and Stratton engines have pressed-in emulsion tubes which cannot be removed to be cleaned.
Hang in there; you'll get it figured out. I fix lawnmowers for a living (certified Kohler Master Service Technician), so I have plenty of practice fixing these sometimes-frustrating machines.
Post a pic of your carburetor. It'll help us figure out what you're dealing with.
thanks man! i have cleaned the bolt out, and can blow air through it on both carbs. and both i think are a briggs one mower is a crafts man thats the older one and the onle with the primer, and the other is a toro w/o pirimer
Pics would help for sure. Sorry, but both Toro and Craftsman mowers used Briggs and Tecumseh engines, and their carbs are a bit different. In fact, some of the older Toros used Suzuki engines that were just labeled 'Toro'. My mom has a mower like this.
Lets see what you are working with and we'll go from there.
Lets see what you are working with and we'll go from there.
alright sounds good. i tink that like blaaster said, it MUST be the float. every port and the carb is spotless, and runs when i pour gas in, but wont suck the gas out when the engine is cold, and has not ran in like a bunch of hrs.
http://www.williammaloney.com/Misc/LawnmowerSnowblowerCarburetorFloodsLeaks.jpg
This was posted earlier, looks some what like this one.
This was posted earlier, looks some what like this one.
That pic posted is of a Tecumseh carburetor. They are easy to clean, but watch out for that small fuel feed hole on the side of the jet 'tower' in the carb. You can see it in the pic posted. This hole must be clean, too, or it wont start.
check the exhaust it may sound funny, but i had this problem and if starting fluid isnt working, its worth a shot. mine was clogged barely letting air through a blast with the compresser and she is still running
i know. and it is. the bowl is have no trouble filling with gas. u know, for such a small and simple carb, they make so much trouble! damn things!
Make sure the U shaped clip that holds the needle to the float tang has some free movement to allow unrestricted movement of the needle.
If the clip is tight against the tang it will stop the float from operating properly.
If the clip is tight against the tang it will stop the float from operating properly.
While the passages inside an ATV or motorcycle carb are no less prone to getting clogged with trash, at least they can be disassembled 100% for cleaning. Lawnmower carbs are often pressed-together, with passages covered by difficult-to-install Welch plugs. They are hard to get 100% clean and sometimes no amount of spray cleaning will do the trick. You either need an ultrasonic cleaning or a new carb to make the engine run right.
Being so small and simple means that they have to be adjusted correctly, they are very, very finiky.
I have a 5hp motor that will start one day, and not start the next.
Once it flooded and filled the crankcase with gas, after checking the float level and making no adjustments, it has behaved itself ever since.
I have a 5hp motor that will start one day, and not start the next.
Once it flooded and filled the crankcase with gas, after checking the float level and making no adjustments, it has behaved itself ever since.
ok so lets work on he older mower first. it was doing the same thing as the other one, but i took the bowl off, and made the float so that it will allow a little more gas in, and now what its doing is i hit the primer 20 times or so, it will start in 2 pulls, then go thumo thump thump, and stall. so i turned the idle screw in all the way, did the same ting, and it started rite up. ran for about 20 seconds, then died out. tires it again, except this time before it died out, i hit the throttle a little, and kept it reving, then what it did was go all the way up to full throttle, and rev really really high, so i shut it off. i tried to turn the idle screw out, and no start no matter what. i would have to reach over and push the throttle for it to run, then it would go to full and i would shut it off.
heres the pics of this carb.
any ideas? im so freaking tired and frusterated with these lawn mower carbs. im almost rdy to hand them back to their owners and say keep them dont pay me. its really pissing me off. and rite now, i need them fixed asap, cause i will litterly have NO time this week for anything.
heres the pics of this carb.
any ideas? im so freaking tired and frusterated with these lawn mower carbs. im almost rdy to hand them back to their owners and say keep them dont pay me. its really pissing me off. and rite now, i need them fixed asap, cause i will litterly have NO time this week for anything.
The tang on that float looks like it has a pitting where the needle rubs.
The pitting will really make a difference to how the float behaves.
Do I remember you saying that you have cleaned the carb a few times, it still looks very dirty to me, especially on the outside.
You should be removing the complete carb and cleaning off all the gunk, and then soaking it in carb cleaner to allow the solvents to get up inside the passages.
The pitting will really make a difference to how the float behaves.
Do I remember you saying that you have cleaned the carb a few times, it still looks very dirty to me, especially on the outside.
You should be removing the complete carb and cleaning off all the gunk, and then soaking it in carb cleaner to allow the solvents to get up inside the passages.
that carb i cleaned like 1 time. i fixed both tho. 1 i know for shure, the other i have to try tomorow when the gas dries up from sitting in the carb. the old one, i had the throttle linkage on backwards, and inside the jet, there was a microspic size hole that i nver saw any of the times i took it appart. so i found it, cleaned it out, and the thing started up in one pull. so that one is done! yay! now the other one (newer toro one). i took the carb appart for like the 30th time, this is the one thats the most clean, i reset the float, got that set up perfectly, and i cleanes out the other holes in the carb. i couldent do that good of a job before, cause i couldent bend the wire the rite way, so i spent a good 30mins on the holes, and unlike the older mower,this one dident have the microspotic hole. i put everything back together, put mu hand over the carb to prime it, pulled it once, and gas came pouring out. it started in 1 pull and ran great. i shut it off, pulled it lightly so it fired once, (this is where when i had to pull it 6 times after to get it started again) then gave it one good pull, and it started rite up. ( it would never do that before). i tried it again, and starts rite up. so i put it away for now, im gonna try it tomorrow morning, if it starts in 1-2 pulls, im golden. hopefully it does.
so hello to $90 and also hello to $350 for the rototiller im hopefully selling on thursday, and i also might have another lawn mower i might be fixing, so another $45, and i might also be cutting a lady's frinds gras for a few dollars 
i <3 $$$ and i might have a job soon too
i <3 $$$ and i might have a job soon too
looks like you are getting on top of it.
With all that money coming in you will soon be good for a loan, Ehh!
Just see if you can clean up the tang on that float it will allow the needle to mate with it better.
With all that money coming in you will soon be good for a loan, Ehh!
Just see if you can clean up the tang on that float it will allow the needle to mate with it better.
