ST-480 2001 Start/stall problem Float Level?

[edwards]

I bought a used ST-480 EZGO workhorse that worked fine for awhile. It is stalling out on hills (backing up hills stalls less frequent than driving up hillls) and sometimes has problems starting. If I tap the side of the carburetor, it generally seems like it gets gas and starts. Sometimes it runs fine for awhile afterwards and sometimes it starts then stalls right away. It does seem that without tapping the side of the carburetor it will turn over but not fire. A few weeks back I took the carb off and completely cleaned it awhile back and it was full of gel like material, but other than starting for awhile and running, it is now stalling on hills again. Power seems pretty low when it is running. Questions:

1) My gut says it is a float level issue, but for the life of me, I cannot find how to adjust the float level. There is no adjustments that I can see. Should I just buy a new float and needle valve, even though these look fine. Is there any way to do a float level adjustment? Does the above sound like a float level problem?

2) Could this be caused by valve clearance? How frequently do the valves need adjusting? I have never done that because I figured it was a carb issue.

[Dave Box]

Hello and welcome to the forum. The very first step would be a compression test. This will determine if the rings are worn and / or the valves are seating. When you do it remember that the engine needs to crank several times and the throttle should be wide open. Report back the numbers and we can pursue a solution.

Dave

[edwards]

Hi Dave,

I concluded that there is no way to adjust the float level on this ST-480 (someone correct me if I am wrong), so I replaced the carb (new $189) and it runs like a top so far. I probably could have just replaced the float and needle and pin, but it is 10 years old and I wasted 15 hours already cleaning and fiddling and recleaning and so I figured just go for the new carb.

Do not have a compression guage.

I did adjust the valve clearances. How bad is it if I adjusted one to slightly less than 0.004"? The 0.004" feeler had to be pushed in relatively hard on one, as opposed to just fitting snuggly. I could readjust if this is important. On one of the valves I could not hold the height at the targeted level because it seems to always move with the wrenching of the nut.

I see you are located not too far from me.

[scottyb]

You should probably redo your adjustments it says .004 not .002 . tight exhaust valves have a tendency to burn their edges. Better you should have .005. But too loose will beat the tappets, etc. to death. Try compensating for the adjustment closing down with the nut and see where it lands... redo it as many times as it takes to get it right and adjust your valves at least once a year.

P.S.
The gunk in the bowl is caused by old gas, I hope you have changed the lines and filter too to protect your new carburetor from getting gunked up too.

[edwards]

Will do and thanks!