Fuel out of overflow hose

[02GF74]

As per title I have fuel coming out of the overflow hose (one of the two hoses that fit to the top of the airbox).

I'm pretty sure I will have to take the carbs off to check the needle valve but am hoping someone may have a tip that avoids that.

Last Sunday I took the carbs off for what is an annual occurrence after the bike standing over winter to clean out the pilot jets.

Previously it would start, run for 2-3 seconds then die.
After the clean it ran fine, I had it running for 5 minutes or more, did notice any fuel coming out or smell it.

I'm am guessing some small particle has got in to prevent the needle valve closing. I have tried rocking the bike to and fro and side to side, didn't fix it.

Any suggestions?

 

[Parminio]

Stuck float. You can try knocking on the side of the fuel bowl with a plastic hammer or the grip of a screwdriver or something to unlodge it. If that doesn't work you'll have to pull the cover and reset it.

 

[Radioguylogs]

Yup...I have succeeded by rapping the bowl with a screwdriver handle.

 

[02GF74]

I got lucky once doing that but not this time.

Carbs off again this weekend. (was hoping to avoid this but knew deep inside that wasn't going to happen)

Note to self, when carbs are off check and clean the needle valves.

Note 2 to self, prior to installing, fit hose and funnel to pour fuel down to check needle valves and floats are operating correctly.

 

[Parminio]

Carbs off again this weekend.

Should be engraved on the side of every Vmax.

 

[petesouthwales]

A quick fix that sometimes works is to disconnect the power supply plug to the fuel pump and run the engine for a while.
The floats will lower due to no fuel being entered and then stop the engine. Reconnect the power and start again and the new fuel being pumped should dislodge any debris. Drain the float bowls after this with the drain screws to flush the bowls.

 

[02GF74]

I've removed the carbs after marking the one that was overflowing.

Taking out and cleaning the needle valve tips, all looked OK except the faulty one that had some brownish coloured stuff around it.

Reassembled and was ready to refit but thought I'll restest them first. Good job I did as one carb on the other side was now leaking.

Took them apart yet again, very gently rubbed the needle valve rubber tips on some very fine wet n dry and restested.

All good..... finally.

Now for some lunch and then refit to engine.

 

[02GF74]

Just wanted to stress how important testing is before final assembly especially if it results in a lot of time /money to disassemble.

I should have done that the first time around - me culpa, especially since I once worked for the company that made the mirror for the Hubble telescope. At the interview I was told it is the smoothest object ever made by man, if it were the size of America, the tallest mountain would be 1 ft high.

NASA did not want to pay for the final testing so it went into orbit. Due to a error, the surface was ground to the wrong shape so the telescope could not focus.

Now it is certainly more difficult and vastly more expensive to fix an item floating in space than back here on earth. It's pretty amazing NASA managed to get someone up (John Grunsfeld and Andrew Feustel) to fix the telescope.

 

[Gbianchi]

I've removed the carbs after marking the one that was overflowing.

Taking out and cleaning the needle valve tips, all looked OK except the faulty one that had some brownish coloured stuff around it.

Reassembled and was ready to refit but thought I'll restest them first. Good job I did as one carb on the other side was now leaking.

Took them apart yet again, very gently rubbed the needle valve rubber tips on some very fine wet n dry and restested.

All good..... finally.

Now for some lunch and then refit to engine.

I used a q tip on all the needle valves then replaced all the needles then checked all the carbs then reinstalled them then went for a ride then synced them then I rested!