Stuttering engine below 4k (FZS600)

[crickleymal]

Too much fuel sounds like the float level was wrong.

[tommyardin]

[size=1em]
I finally go the Fazer back from the workshop. The problem was with the carboratour and valves. There was too much fuel getting into it and that was a reason why it was losing power. Proper cleaning, including some liquid added to the fuel, solved the problem. Now it runs like brand like Thanks again for all advices.
[/size]

[size=1em]Strange ending to the story.[/size]
[size=1em]To much fuel means flooding and that points to stuck float bowl needles usually, or completely blocked air intake, although that would have been diagnosed as choked rather than flooding.[/size]

[size=1em]I would be interested to know what his workshop charged for the fix as it might indicate the amount of time was spent on it.[/size]
[size=1em]Fuel additives can be helpful in giving the the old carbatooters a freshen up and can help with descale or varnish removal, but if something like the needle valves or jets are completely blocked the answer is to blow them out with a powerful air line or replace them if they don't comply.[/size]
[size=1em]The bodies of carbs of yesteryear had fuel ways or capillaries running through the main cast alloy bodies if this still applies to the more modern carbs then theses need blowing out with the airline as well as it's no good having a nice clean jet with a mountain of crud behind it. [/size]

[size=1em]As Darrsi said a bit more info would be helpful to know and could help others diagnose their own problems. [/size]

[feral kid]

As you've probably noticed I'm not very good with technical details, but I will try to explain what I understood and remembered.
I took it to the workshop twice.
That's what's been done at the first visit:
- Air filters changed,
- Inlet manifolds Gaskets changed (I think),
- Spark plugs changed,
- Spark plugs cups changed.
Above things didn't solve the problem, so few weeks later I took it back and here what's been done:
- Carborauter cleaned using ultrasonic cleaner,
- Adjusting and syncing carborauter,
- Checked valve clearance,
- and that fluid for carborauter cleaning
After the second visit it runs awesome, the stuttering problem is gone and it feels like it has much more power than before the problem started, but I had to spend £300.

[darrsi]

Okay, so the carbs were cleaned properly, hence the bill.

[tommyardin]

Expensive but sucsessful, jobs done  :thumbup :thumbup :thumbup

[Oldgit]

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