Float needle sticking closed???

[Spelli]

I seem to be having a problem with the rebuilt carbs. On my Gsx1100et

At first I was getting some poping in the exhaust which I put down to a lean condition caused by air leak. changed the carb mounting rubbers which had gone hard. This at first appeared to solve the problem. 

Started the bike this morning and it started straight away, run for a few minutes and then started to die like it was running out of fuel. 

then it stopped and would not restart. 
Spark ok. Plenty of fuel. Opened the float bowl drains and very little fuel came out. 
 

attached a remote fuel tank so as to eliminate any fuel tap issues and found fuel was still not flowing even though the one of the float bowls was empty.

Pipework is intact. Looks to me like the needle valves have been sticking closed.

dismantled the carbs …again and all looks ok. Needle valves appear to open and close as needed. 

what am I missing ? Could the replacement needle valves and seats be giving me the problem. Should I replace them again?

I have seen reference to adapters that fits into the float bowl drains enabling clear pipes to be attached so as to see the actual fuel level in carbs. 

Any idea where I can buy these  or how to make them  ?

Any advice would be appreciated.

Thanks 

Edited January 19, 2023 by Spelli

[TonyGee]

are you saying all 4 are sticking ? very unusual if it is !!!  i'd be checking the fuel line into the carbs as it sounds like a blockage. 

[Spelli]

Think you are right, that doesn’t make sense  that would be too much of a coincidence 

Have you seen those adapters to fit into the drain plugs?

Edited January 19, 2023 by Spelli

[TonyGee]

1 hour ago, Spelli said:

Have you seen those adapters to fit into the drain plugs?

ive seen them but don't know where to get them !!!  never had an issue with checking the float height the normal way. 

[Gixer1460]

How are your engineering / fabrication / bodging skills? Measure the thread on the float bowl drain screws, then make / turn up a nipple with that thread and bored through, attach clear tube to each and cabe tie to something to keep vertical with open end higher than the top of float bowl - et voila - level guages! Don't forget to turn the fuel supply off when removing them ! ! !

[ral]

As TonyGee says, sounds like blockage, main fuel line feeds the T connector in between the two carbs in the middle, number 2&3 these would fill first, once full the fuel should then flow through the straight connectors between 1&2 and 3&4, start with removing main fuel feed line to see if it’s full of crap.Fuel normally finds its way through the smallest of gaps so might be filling float bowls when stood hence initial start up, the weak flow is starving the carbs when running by the sounds of it

[Jaydee]

Was there any old fuel in the tank after the  carb rebuild? If there's any water in the fuel it can react in the carbs creating petroleum jelly and clog everything. 

[Spelli]

I have de rusted and lined the fuel tank. The carbs have been striped and ultrasonic cleaned and have used an inline fuel filter. So I think everything should be clean.

I think this re routing of hose to incorporate the filter has caused the main fuel pipe kink. 

The pipe looked ok to the eye but it is hard to see when the tank is fitted but I think it is the only reasonable explanation. 

Think I need to route the pipe with a less tight curve or find a way to stop it kinking. 

[Spelli]

4 hours ago, Gixer1460 said:

Measure the thread on the float bowl drain

The thread is quite fine. Tried  the local nut and bolt supplier  but no luck. 
was thinking of buying spare carb drain plugs and drilling through and soldering  on a tube to make a connection for the tubes. 

Think that should do it.

[BigT]

I'd check to see if the unnecessary fuel filter is flowing fuel

[DAZ]

3 hours ago, BigT said:

I'd check to see if the unnecessary fuel filter is flowing fuel

Have you got the fuel filter the right way round some have a small arrow to indicate direction of flow an really easy mistake ..... Ask me how I know ....

[Gixer1460]

7 hours ago, BigT said:

I'd check to see if the unnecessary fuel filter is flowing fuel

And a fuel filter is NEVER unnecessary when fitted to an 'older' bike !

[Spelli]

9 hours ago, DAZ said:

Have you got the fuel filter the right way round

Thanks for that suggestion.

I will check that out tomorrow 

 

[Spelli]

5 hours ago, Gixer1460 said:

fuel filter is NEVER unnecessary when fitted to an 'older' bike !

I can not face getting muck in those lovely clean carbs. They took a lot of effort to get them clean, don’t want to block them up again just for the sake of a bit of fiddling with the pipes. 

[BigT]

If you don't know that your petcock has a fuel filter, well

If you have a fuel filter in line, it can't be for a FI motor

 

[DAZ]

5 hours ago, BigT said:

If you don't know that your petcock has a fuel filter, well

 

 

Yes most taps have a screen but on a 40+ year old bike who knows what previous bodgery has gone on ,and they're generally quite a coarse mesh you only have to look at the slurry found in most float bowls to see that,so a finer online filter isn't necessarily a bad idea 

[Spelli]

8 hours ago, DAZ said:

Yes most taps have a screen but on a 40+ year old bike who knows what previous bodgery has gone on ,and they're generally quite a coarse mesh

The Petcock filter is intact and from memory it looked fine enough to me. 
I am thinking that the Petcock filter may well be sufficient. To be honest I am not entirely happy with the in-line fuel filter as it opens up the potential of leaking fuel onto a hot engine which never a good idea.

[Rijko]

I have had something like that long ago.
In that case, the float bowl gasket was too wide, and when mounting the float bowls the gasket would press the float in the highest position and keep it there, so all 4 float needles were shut.

Edited January 21, 2023 by Rijko

[DAZ]

16 hours ago, Spelli said:

The Petcock filter is intact and from memory it looked fine enough to me. 
I am thinking that the Petcock filter may well be sufficient. To be honest I am not entirely happy with the in-line fuel filter as it opens up the potential of leaking fuel onto a hot engine which never a good idea.

Whatever your happy with, for carbs usually a 40 micron filter is good enough though finer is better as long as you have the required flow  , injection filters can be 10 micron or less . Unless you know your tank is pristine inside a GOOD quality sevicable  filter(not the £2.99 car boot crap) and ethanol resistant lines and fittings is an investment and strikes off potential carb issues . Just my opinion .