2072 Troubles

[j4c11]

My 2072 has been having an issue where it will fire up and run, but once I shut it off I can't start it back up for a while. Maybe if I come back the next day and try to start it again, it fires right up again.nAn hour or two generally won't do it. I decided to try and take it apart and see what's going on, pulled the spark plugs they are black as night. I turned the engine with the spark plugs out, not sure what I was trying to accomplish but the right cylinder is spitting out plumes of gasoline vapor like a volcano, it soaked my hand when I put it over the spark plug hole, while the left one just puts out compressed air that smells like gasoline (left and right as sitting in the drivers seat). Any direction from here?

Thanks,

Jordan

[J-Mech]

Sounds flooded......

[j4c11]

What's causing it? Is the needle valve on the carb sealing against the seat? It's a huge amount of gasoline.

[J-Mech]

Most likely. That's about the only thing it can be, needle valve not sealing. Pull the carb, take it apart and clean it. Pull the dipstick too. Check for gas in the oil. If it smells like fuel.....drain it/change the oil. Looks for bits of rubber in the fuel bowl on the carb. If you see any little black pieces, get a fuel pump and replace the lines and flush the fuel system. You still have the Mag in yours right?

[j4c11]

Originally Posted by J-Mech

Most likely. That's about the only thing it can be, needle valve not sealing. Pull the carb, take it apart and clean it. Pull the dipstick too. Check for gas in the oil. If it smells like fuel.....drain it/change the oil. Looks for bits of rubber in the fuel bowl on the carb. If you see any little black pieces, get a fuel pump and replace the lines and flush the fuel system. You still have the Mag in yours right?

Yes it's got the Mag 20. Thank you, I will pull the carb tomorrow evening and report back.

[Tacosteelersman]

Avoid contacting rubber and carb cleaner, it will swell the rubber it comes in direct contact with. Don't forget there is a seat the needle contacts to stop gas flow. When I clean carbs I strip the coating off a bread tie and poke the wire into all the tiny holes in the carb throat. Also check your float. They can get a crack or hole and partially fill with gas. Usually I shake it next to my ear and listen for sloshing.
Good luck.

[J-Mech]

Originally Posted by Tacosteelersman

Avoid contacting rubber and carb cleaner, it will swell the rubber it comes in direct contact with. Don't forget there is a seat the needle contacts to stop gas flow. When I clean carbs I strip the coating off a bread tie and poke the wire into all the tiny holes in the carb throat. Also check your float. They can get a crack or hole and partially fill with gas. Usually I shake it next to my ear and listen for sloshing.
Good luck.

As a note, there is a more important hole(s) that you didn't mention.

These holes:

NJ1.2.2.jpgNJ2.jpg


There a some small holes in the carbs. But they usually don't plug off as often as this one does. Now, all this assuming that we are working on a Carter/Kohler carb. If it's a non-adjustable Walbro..... no main needle, so it's irrelevant. The OP is having a flooding problem. Which would not be caused by a plugged up carb. However, your advice is sound. You should always clean a carb well, checking all passages. Just make sure you don't leave out the holes in the needle. In his case, no real need for carb cleaner. Just take it apart and flush it out. (Brake cleaner will work fine.) More than likely, it's a failing fuel pump and there is a piece of rubber stuck in the float (needle) valve. Depending on which model of carb is on the motor, it may not even have a replaceable seat. Also, it should have a plastic float.

[Tacosteelersman]

Well said. I have seen plastic floats fail especially on the seam.
Also a reminder, as Jonathan said don't forget to check for gas smell on the dipstick.
Great info.

[j4c11]

Thank you guys, great info . I'll take the carb off after work and see what's going on in there. When I bought the tractor it had been sitting for about a year and a half with a tank full of gas. The carb was incredibly dirty on the inside , all sorts of slime and it had all this crystal like sediment at the bottom that had nearly eaten a hole through the bowl. I wonder if the old gas caused damage to anything else, like the fuel pump or the needle valve seat, although if I remember correctly the seat is brass. Either way, I will report back this evening. Just in case, what model carburetor is on these? It looks almost identical to the #30 that's on the K321 but it doesn't have the #30 stamped on the inside.

[j4c11]

Ok wtf is this stuff, I had this carb clean as a whistle about 4 months ago.Only used fresh gas since. It's all over the float too, some sort of gel-like beads of "stuff".