"Blow it up"

[GTGS]

I had this problem a few weeks ago with the bike cranking and not wanting to fire even with full choke. It would happen randomly after it ran fine even hours before. I wrote it up in here and thought it was a vapor lock or something. You guys suggested I clean out the gas cap vent. I did and it was fine till the last few days.
I rode it to work yesterday and everything was fine. When I came out of work I cranked it for a bit and it would'nt fire. Usually it cranks right up. The battery was getting low so I jumped it. Crank but no fire. I remembered someone on here suggesting blowing into one of the carb vent tubes. I did that and it fired right up and proceeded to dump gas out the airbox dump tube. I rapped on the float bowls and it stopped leaking. I rode it home no issues. Tonight when I got home I tried it. Same deal. Blew in the tube, it started, gas out the overflow. etc.......What is going on? The bike runs excellent once started. It's getting less random and more regular. FYI The tank was cleaned and sealed over the winter, new OEM petcock, and carbs properly cleaned.

 

[Dave8338]

Inline fuel filter installed?

 

[koolaid_kid]

Sounds like a stuck float, usually the needle and seat. I suggest pulling off the airbox boots and seeing which carb(s) is/are overflowing...

 

[GTGS]

No inline filter.
I don't normally have any leakage out of the airbox at all even if I leave it on prime so I'm pretty confident that they are seating OK. I only get leakage if the thing wont start and I have to blow into one of the vent tubes. I'm trying to understand why it wont start in the first place. Secondly I want to know why blowing into the vent tube all of a sudden corrects the problem.

 

[Dave8338]

No inline filter.
I don't normally have any leakage out of the airbox at all even if I leave it on prime so I'm pretty confident that they are seating OK. I only get leakage if the thing wont start and I have to blow into one of the vent tubes. I'm trying to understand why it wont start in the first place. Secondly I want to know why blowing into the vent tube all of a sudden corrects the problem.

The blowing into the vent tubes, pressurizes the bowls and forces fuel up and through the carb passages. As to why you are now having the problem, It may be that the float valve(s) are sticking closed and not allowing enough fuel to flow, leaving the choke circuits dry an ineffective.

You may try running a healthy dose of Seafoam through the next tank or two and see if that helps the problem. The only real FIX, is to tear into the carbs and do it right.

 

[GTGS]

What does the seafoam do and where can I get it?

 

[four_shot]

It's an all round do gooder of a product that helps to break down varnish in the fuel system. It also makes a kick A$$ fuel injector cleaner (but thats for a different forum). It's available at all parts stores. Wal-mart, K-mart, and the like. usually $5 to $8

 

[GTGS]

OK the next morning I tried it and the bike fired right up but I left it home. I picked up some seafoam after work and put some in the tank. Went to start it and it just cranked. Did not start. I gave it a shot of quick start and it fired right up. I rode it 45 miles and it ran nice and smooth. I tried it again this morning. No start. It is not getting gas when cranking. The plugs are dry. Usually on choke the thing jumps to life but not lately.

Is it time to tear it apart and re-clean the carbs? I'm dissapointed because she has been running excellent.

Any other ideas before I tear into it?

 

[sackman]

Kinda sounds like ya got a petcock vacuum problem. Try pluggin the vacuum line from the petcock to the carbs. You'll have to plug the vacuum port at the intake boot also. Then turn the gas to the "on" postion. If it's a vac prob that would be the by-pass for it. At least it has worked for me.