Anyone Know about Holley Carburettors

[Gary Flinn]

Hi All

Can anyone offer advice on Holley Carburettors?

I'm experiencing difficult starting from cold (but once warmed up the car starts first turn of the key), occasional stalling on idle and hesitation/hunting when running on very light throttle settings.

The car runs fine when accelerating through the gears and cruising at 60/70 MPH.

I have set the float height in line with the Holley instructions, but have not adjusted anything else.

I have recently rebuilt the carb after having Over fuelling issues, fitting a new Needle Valve, Power Valve and Accelerator Pump Diaphragms, together with cleaning everything and fitting all new gaskets, so not sure if it's something I've done.

The Carb is a 2300 Range 2 Barrel 350CFM Type fitted to a small block Ford V8 Engine.

I'm thinking it's something to do with the carburettor, due to the fact the car runs fine most of the time, it's just the stalling and hesitation/hunting on light throttle setting

Any advice welcomed

Gary    

[Pete Lewis]

slow running jet blocked upset slow running and idle

does the choke flap close and does the automasity spring allow the flap to open as the intake sucks so the flap opens vibrates on

each intake stroke  ??  normally a tap with a finger shows the flap will 'bounce'

Pete

[Pete Lewis]

if the 2nd barrel is to open at idle the main barrel with the choke wont work well    as air takes the easy route 

not sure about holly  we had them on  Dodge 50series with a chrysler  engine inline 6

Pete

[Gary Flinn]

12 hours ago, Pete Lewis said:

slow running jet blocked upset slow running and idle

does the choke flap close and does the automasity spring allow the flap to open as the intake sucks so the flap opens vibrates on

each intake stroke  ??  normally a tap with a finger shows the flap will 'bounce'

Pete

Pete

Thanks for the response, I've attached a PDF breakdown of the 2300 range Carburettors Parts.

Do you think it may be a gummed up or sticking Idle needle as Item 42 that is causing the stalling?

Gary  

 

Holley 2300 Parts.pdf

[Pete Lewis]

so theres a thermal coil spring between the choke cable lever and the choke flap plate   does this need resetting  

a bit like old auto chokes these springs go weak and need a bit of rotation to reload the flap 

the idle needle   dont know how that works  but any residue will slow its operation 

presume this is like a normal idle mixture adjuster ?

it relies on small drillings up to the top face so air can bleed in  is any of the small orifices clogged ?

they normally exir close to the edge of a closed throttle plate   as does the dizzy vac port   all small easy to get bunged up 

Pete

[Gary Flinn]

Pete

My carb is fitted with a manual choke, I was told this wasn't required for cold starting by the PO as it caused flooding when he tried to use it?

The car used to start fine when cold, it just needed a bit of revving for a minute or so, then it would settle down and Idle smoothly.

I think the idle speed is set by adjusting the Idle Needle, some Holley's have two idle adjustment (4 Barrels) but I think mine only as the one with it being a 2 Barrel.

I will try and find time at the weekend to remove and clean the Idle needle and opening, I didn't remove it when I changed all the other items

If there's no improvement, I may bite the bullet and get it booked in with a local specialist I know.

I've been told by Holley Tech department to check the vacuum readings, but I don't have a suitable gauge 

Regards   

Gary 

[Pete Lewis]

i recommend    https://www.carburetterexchange.co.uk/  if you get stuck 

odd a choke is not worth using   a cold engine needs a rich mix to fire up , if its caused flooding then some flap and  fast idle  settings seem wrong 

dont know on your holly but the choke flap often has a small hair spring to give the closed flap some unloading springability ! 

these can have knotches on their small lever to allow for more or less flap tension    ( this might be a bum steer ) we played with holly's in my exhaust emission facility 

but never got that involved with any problems  they seemed fault free  that was back in the 80s  so sorry bit foggy now  

Pete