Adjusting Tucumseh carb

[snoblowerguy]

Ok I was given an old Ariens Sno-Thro with a Tuc 5hp engine.

It runs but kinda rough. I took off the bowl checked the float for leaks and cleaned what I could.

Now my problem is> From what im reading the adjustment screw on the bottom of the bowl should be set to at least 1 full turn out. But I cant get it to run right that way and somewhere between 1/2 and 3/4 seems to be the sweet spot. Only thing is the carb spits a very tiny bit of fuel and the exhaust has a little black in it. Might just be carbon burning off i dont know.

I plan on pulling the muffler and seeing if its clogged.

Just wanted to get some input from people who know what there talking about as im lost.

It seems to be running pretty good now but im not sure what its going to do once I start using it. Such as bog under load. I did put it in 4th and let off the clutch and it didnt bog it just dragged me down my driveway.lol

Any input would be great.

 

[Egon]

somewhere between 1/2 and 3/4 seems to be the sweet spot.

Run it there.

 

[jhwentworth]

If the motor runs best at ½-¾ turns on the main jet then it must be getting fuel somewhere. The black smoke in the exhaust and spitting fuel sure sounds like a rich condition. 1-1¼ turns on the main jet is usually about right.

Running it where it is surely is an option, but you may have second thoughts some night during a blizzard in February.

Check the condition of the float (sometimes a small hole allows fuel to enter the float) and the needle and seat. Manually check the action of the needle and seat to verify that fuel is shut off with the float parallel to the vase of the carb. You can bend the tab that holds the needle to adjust the fuel level. Use a mirror to inspect the seat; any dirt or a damaged seat can cause excess fuel to enter the bowl. Another thing that can cause excess fuel is a plugged vent hole. This vent allows air to leave the bowl as fuel enters. Any Tecumseh dealer should have a packaged carb kit to repair your carb, just add in a float and the bowl for a pretty complete rebuild. You might be happy you did some night in February during that blizzard. I've always figured that with snowblowers you only need them a fews times a year, but, when you need them, you really need them, and the $25 carb kit seems like cheap money.

 

[snoblowerguy]

If the motor runs best at ｽ-ｾ turns on the main jet then it must be getting fuel somewhere. The black smoke in the exhaust and spitting fuel sure sounds like a rich condition. 1-1ｼ turns on the main jet is usually about right.

Running it where it is surely is an option, but you may have second thoughts some night during a blizzard in February.

Check the condition of the float (sometimes a small hole allows fuel to enter the float) and the needle and seat. Manually check the action of the needle and seat to verify that fuel is shut off with the float parallel to the vase of the carb. You can bend the tab that holds the needle to adjust the fuel level. Use a mirror to inspect the seat; any dirt or a damaged seat can cause excess fuel to enter the bowl. Another thing that can cause excess fuel is a plugged vent hole. This vent allows air to leave the bowl as fuel enters. Any Tecumseh dealer should have a packaged carb kit to repair your carb, just add in a float and the bowl for a pretty complete rebuild. You might be happy you did some night in February during that blizzard. I've always figured that with snowblowers you only need them a fews times a year, but, when you need them, you really need them, and the $25 carb kit seems like cheap money.

Ok I check that stuff. I did check the float for leaks and there wasnt any.

Also the amount of black smoke and spitting gas are very little.

Im going to look around for a rebuild kit. I planned on doing it anyways so I can make it through the winter with no worries.

Also the needle seemed to wobble when I put it back in so maybe tat seats gone. Ill be pulling it apart today to check it.

 

[2manyrocks]

If you are going to rebuild it, sometimes it helps to soak the whole carb in cleaner overnight and then blow it out with compressed air. I hesitate a bit in saying this because I don't know if there is anything in this carb that the cleaner would mess up-but if you are replacing the seals, etc. with parts from a new kit, probabably would be okay to soak it. You can buy a gallon of carb cleaner at the auto parts place and sit it in it overnight.