Author Topic: 1978 F2 float valve  (Read 713 times)

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Offline Read Replica

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1978 F2 float valve
« on: May 10, 2010, 08:26:49 AM »
Of the four float valves in my 1978 750 F2 carbs, two of them have little pins at the opposite end to the seating tip that will move up and down and sit proud of the valve. The other two are sitting flush with the valve body and do not protrude. Is there a simple way to get the two that do not protrude out of the valve body and moving again?
I am trying to set float height and this discrepancy between the valves is not helping me.

cheers
Andy

Offline flybox1

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Re: 1978 F2 float valve
« Reply #1 on: May 10, 2010, 08:43:43 AM »
Andy,
try soaking them in carb cleaner overnight.
depending on how long they have been that way, they might be shot.
the little spring inside needs to provide positive pressure to fully close the fuel valve.
i'd look for new OEM...for all 4.
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

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Offline eurban

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Re: 1978 F2 float valve
« Reply #2 on: May 10, 2010, 08:50:06 AM »
Order up a set of replacement float needles would be my suggestion.  The pins should plunge up and down in the needle freely and you can't set your floats correctly until the pins are functioning.  You can try some spray cleaner or lube but I wouldn't soak the needles in caustic carb dip as the rubber will be affected.  Perhaps a soak in some thing like simple green would free them up?

Offline Read Replica

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Re: 1978 F2 float valve
« Reply #3 on: May 10, 2010, 12:36:22 PM »
Cheers for the response guys. managed to free up one valve but it is still a little sticky. However, have taken the plunge and ordered a set of 4 from my local Honda dealer.

Have fun
Andy