Section : Carburettors

Fuel coming out of the air filter box???

Posted By : Ian Preece, 15-Oct-2006, 02:46pm

Tried to start my spit today and after spinning over for a while, fuel began to come out of the overflow pipe on the rear carb.
Not wanting it to drip onto the manifold, I connected the overflow off the 2 carbs together with a piece of tube.
The next time I turned it over, the fuel was dripping from the air filter housing.
Is this likely to be caused by a jammed float?
The last time I drove this car, I did a 50 mile journey with no problems.
It's a bog standard 1980 1500 spitfire running HS4 su's and standard filters.
Any help would be appreciated.... carbs aren't my strong point!

Followups :

Fuel coming out of the air filter box???

Posted By : Charles Bushell, 15-Oct-2006, 03:49pm

Sounds like a sticking needle valve in the float chamber, can be caused by dirt in the fuel line.
- Fuel coming out of the air filter box???
  
  Posted By : Julian Saul, 15-Oct-2006, 04:08pm
  
  I had a lot of trouble with the standard needle valves, not adequately sealing off the fuel flow, resulting in, amongst other things, irregular engine idle, fuel leakage at the float chamber and excessive fuel consumption.
  Having recently fitted grose jets, it would seem to have cured the afore-mentioned problems.
  - Fuel coming out of the air filter box???
    
    Posted By : Ian Preece, 16-Oct-2006, 03:27pm
    
    Thanks for the replies, I'll have a look in the carbs!
    - Fuel coming out of the air filter box???
      
      Posted By : Ian Mulford, 16-Oct-2006, 03:37pm
      
      You'll be wanting to look in the float chambers, not the carbs themselves
Fuel coming out of the air filter box???

Posted By : Edward Fletcher, 27-Nov-2006, 12:40pm

Hi Ian,

Did you cure this ? I have the same car and same problem
- Fuel coming out of the air filter box???
  
  Posted By : Jon Morton, 27-Nov-2006, 01:04pm
  
  Since the removal of lead from fuel the lubricating nature of it has been lost, which adds to the problem of sticking float chamber needles. Add a splash of Redex or similar to help prevent it, but sounds a little extreme in your case so wouldn't cure it.