Lawn boy 4 cycle
- Thread starter mikehouse
- Start date
Yes, hundreds of times. I’m will to bet you will find that you have spark, but no fuel getting to the Tecumseh carb. Time to clean and rebuild the carb with Tecumseh part number 631021B. Follow the procedure I use, plus new plug and air filter.
Needle and seat replacement.
Remove the carb, and then remove the float bowl. Check the float bowl jet (which is the bowl screw) and make sure the jets both horizontal and vertical are clean and open. Tip the carb upside down and remove the float pin and float with needle attached. Look in the float needle passage and you should see the red float seat at the bottom of the passage. This is where a #5 crotchet hook would come in handy as you need to remove this seat. If you have no hook, but compressed air, you can blow through the fuel inlet and try to pop the seat out. Put your thumb over the passage to prevent the seat from flying who knows where. No air or hook try bending a stiff paper clip to dig the seat out.
I would either give the carb a good 24 hour soaking or have it ultrasonically cleaned at this time.
With the seat out clean the passage way with carb cleaner. Now you must find a drill bit slightly smaller than the passage way, to be used to press in the new seat. Apply a very, very small amount of a very light lube to the new seat. 3-1 oil or lighter, to help seat it better. Carefully insert the new seat in the passage way with the rings on the seat down toward the carb body. Slowly and carefully force the seat down with the back end of the drill bit. Once it is seated, check to see that it did not flip and the rings are up. Next check to make sure that the float does not have any liquid in it. If it does, replace. If everything looks correct, attach the new needle to the float and install with the float pin centered. It everything is correct, the float should seat level to the carb body, when looking at it upside down. If everything looks good reattach the float bowl, making sure that both the bowl gasket and the nut gasket seal properly. Reinstall on the engine and test unit. Remember to have patience and take your time. Good luck, but I don't think you'll need it.
PS: On the side of some Tecumseh carbs you will find a plastic cover. Under this cover will be an idle jet. Remove it and check to see that the jet is open both horizontally and vertically. You should be able to push the old float needle wire through the vertical opening.
Needle and seat replacement.
Remove the carb, and then remove the float bowl. Check the float bowl jet (which is the bowl screw) and make sure the jets both horizontal and vertical are clean and open. Tip the carb upside down and remove the float pin and float with needle attached. Look in the float needle passage and you should see the red float seat at the bottom of the passage. This is where a #5 crotchet hook would come in handy as you need to remove this seat. If you have no hook, but compressed air, you can blow through the fuel inlet and try to pop the seat out. Put your thumb over the passage to prevent the seat from flying who knows where. No air or hook try bending a stiff paper clip to dig the seat out.
I would either give the carb a good 24 hour soaking or have it ultrasonically cleaned at this time.
With the seat out clean the passage way with carb cleaner. Now you must find a drill bit slightly smaller than the passage way, to be used to press in the new seat. Apply a very, very small amount of a very light lube to the new seat. 3-1 oil or lighter, to help seat it better. Carefully insert the new seat in the passage way with the rings on the seat down toward the carb body. Slowly and carefully force the seat down with the back end of the drill bit. Once it is seated, check to see that it did not flip and the rings are up. Next check to make sure that the float does not have any liquid in it. If it does, replace. If everything looks correct, attach the new needle to the float and install with the float pin centered. It everything is correct, the float should seat level to the carb body, when looking at it upside down. If everything looks good reattach the float bowl, making sure that both the bowl gasket and the nut gasket seal properly. Reinstall on the engine and test unit. Remember to have patience and take your time. Good luck, but I don't think you'll need it.
PS: On the side of some Tecumseh carbs you will find a plastic cover. Under this cover will be an idle jet. Remove it and check to see that the jet is open both horizontally and vertically. You should be able to push the old float needle wire through the vertical opening.
mikehouse
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I've seen your instructions on another post,and you are dead right!!! However i did all the same exact things to my B&S.My thing is whats with the back? I tried to open it and can't.I did however get this thing started after priming a bunch of times but wouldn't stay running.
mikehouse
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Back meaning the back chute for the mulching block.But besides that,This mower goes for close to $500.Why would people not clean it at least Jeez? I'm just gonna clean the bowl,jet screw,and hope it fires up.Another thing,the handle will not lock in place.I've tightened it as much as i could to no avail.What's good for that?
mikehouse
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Well i thought no question was a bad question? I should have asked the difference between 4 cycle and 4 stroke? But i looked it all up on 'tube ala donyboy73 and Steve's small engine saloon.Plenty of ways to peel a grape.Thanks though.
mikehouse
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Hey Rivets.I need your expertise on this 4 cycle mower if you don't mind.The problem i have is the handle.Well...it won't stay up.I tried a washer and it didn't really help.I figured if i took the whole star off and went to Ace hardware i could get an exact fit washer and maybe that'll do it.But i wanted to check with you 1st to see if you've come across this oroblem befoee and what did you do?
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Most of the time I find that replacing the nylon washer solves the problem. Lawn Boy part number 107-3947 and cost about a buck a piece. If you have a lot of play, I’ve even doubled up on each side. Don’t like rubber unless you never want to move the handle. Make sure the handle control is in good shape and working properly before buying parts