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Why is fuel spitting from front carb on deceleration

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carChips Avatar
carChips Victor Harnish
Kelowna, BC, Canada   CAN
1933 MG Magnette
1973 Triumph Spitfire 1500 "Chip"
1989 GMC Sierra 1500 "Bush Truck"
Larry has fuel coming out the float bowl overflow, which has nothing to do with the dashpot and metering needle.

Larry, HS4s or HS2s? HS4s have self centering needles.


In reply to # 1595450 by Mgro1959 If is is SU carbs then the needle is probably not centered properly and piston hanging up. Undo the jet nut on bottom with the dashpot piston needle assembly in place raise piston up and down with middle finger a few times letting it seat. Tighten the jet nut with piston seated. This should center the needle and allow piston to seat and shut off fuel.



'S all for now
Vic

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spitfire50 Avatar
spitfire50 Paul Mugford
Rochester, N.H., USA   USA
In reply to # 1595450 by Mgro1959 If is is SU carbs then the needle is probably not centered properly and piston hanging up. Undo the jet nut on bottom with the dashpot piston needle assembly in place raise piston up and down with middle finger a few times letting it seat. Tighten the jet nut with piston seated. This should center the needle and allow piston to seat and shut off fuel.

Rob,
You seem to have confused the metering needle with the float needle. Different parts with different functions.
Centering the metering needle will make the piston return to the lowest position more reliably. That puts the metering needle where it should be for correct idle mixture.
The float needle is part of the valve that shuts off the fuel when the level is correct in the float chamber. This also sets the level in the jet so the air through the throat of the carb can draw the right amount of fuel to give the correct mixture. If the float needle leaks, too much fuel enters the float chamber and some of the excess will come out through the vent/overflow.
The metering needle doesn't shut the jet. It always has some clearance around it for fuel flow.
All the best,
Paul

Doug in Vegas Avatar
Doug in Vegas Douglas D
Las Vegas, NV, USA   USA
It just started doing this so it's not a backwards gasket.

I'd check if a Grose jet is leaking. Two little balls that have to be free of debris or they leak.

Then again, could be an internal gasket leak.

I'd order a rebuild kit and ask the guys the best initial number of turns out.

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