GZ250 Won't Start

[viking79]

Hello, I am new to this forum and have a GZ250 that suddenly won't start after winter.

Things I have done:
Drained the fuel, replaced with 1.5 gallons of fresh fuel.
Checked spark (spark is good).
Starts and stays running with starter fluid (actually MAF cleaner), dies as soon as I stop spraying.
Does not start with fuel in "pri" position (nor other positions).
Removed and cleaned out some passages in carb, no help, but didn't take it very far apart, just took the bowl off and removed the jets and blew compressed air through the passages.
If fuel set to "pri" airbox will fill with fuel and drain out bottom
Fuel drains from bottom of carb if I open the bowl screw.

Any thoughts on how to trouble shoot this? If the petcock is bad it should still run in "pri" right? It doesn't seem like it should leak fuel out the air box in this position, or is that normal? Seems like a carb or maybe fuel delivery issue.

Thanks!

Eric

[derbydave]

Sounds like you have a gummed up primary jet. The primary jet is on the bottom side of the carb under a brass cap that needs to be drilled out to access it. It also sounds like your float is not adjusted properly or the needle and seat is not sealing.

[Water Warrior 2]

Any time your bike is parked for an extended time you should use Stabil in a fresh tank of gas. Run it for a short time to get the mixture into the carb. You shouldn't have anymore problems with the carb getting gummed up and hard to start.

[blaine]

Originally Posted by Water Warrior 2

Any time your bike is parked for an extended time you should use Stabil in a fresh tank of gas. Run it for a short time to get the mixture into the carb. You shouldn't have anymore problems with the carb getting gummed up and hard to start.

I found SeaFoam to be better than Stabil.....I use it once a month & always in a full tank of fuel when storing for winter.

[viking79]

Thanks, I will take the carb off and look for that primary jet. Once I drill off the cap, how do I replace that (maybe it will make more sense when I get it apart, any link to procedure?) Also, anything about how to adjust float? Haven't actually done one before

Yes, will use stabil or seafoam or similar this time, didn't drive it much last year so fuel was pretty old.

Eric

[viking79]

Okay, looking at generic carb view, the float closes the needle valve and stops fuel from flowing in, since fuel leaks through on prime position, might not be sealing right?

[derbydave]

Two excellent videos on carbs

[viking79]

Thanks! It was the float and needle. The float wasn't engaging the needle at all so it wouldn't close and I imagine it was flooding immediately. I bent the tab slightly on the float so it could close the needle. I almost wonder if a part is missing. I will go watch those videos you posted. Thanks again, Eric

[viking79]

Great videos, looks like I might need to take the float off again and adjust to spec, and I think the sudden change is that the damper in the needle valve is not working so it stopped closing.

Eric

[Water Warrior 2]

Originally Posted by blaine

I found SeaFoam to be better than Stabil.....I use it once a month & always in a full tank of fuel when storing for winter.

Perfect. A friend of mine swears that Seafoam is the best thing since sliced bread. He has used it to treat carbs with the Seafoam spray can just by spraying into the carb throat.