Cutting out under load

[Bruce_the_GT6]

Hi

 

Firstly - Happy New Year

 

I currently have a problem with my 69 GT6 Mk2. Recently in a run the GT6 cut out while under load going up a hill. Just before cutting out the running felt bogged down and under powered, before sending a loud backfire and stopping. Getting it restarted involved keeping my foot to the floor until all the cylinders ran evenly, but still got bogged down if going over 3000 rpm and higher than 2nd gear. On returning to the workshop the plugs were removed and found to be blackened, so I'm hazarding a guess at flooding under load.

 

My setup is:

 

Malpassi Fuel King pressure regular (includes fuel filter) - set to 2 psi

Refurbished original fuel pump

Strombergs Carbs

 

Could this problem be related to the fuel pressure being too high or is this a carb tweak? Are there any other possible solutions?

 

Many thanks, Frank

[Eddie]

I had a similar problem on a Ford. It turned out to be crud from inside the fuel tank partially blocking the fuel filter. Normally this was not a problem but under hard acceleration not enough fuel was getting through causing hesitation and eventually to the engine cutting out.

[Pete Lewis]

Backfires = condenser

 

but crud blocking the float needles comes to mind

pete

[Dave C]

I had a similar problem with a 1500 Spitfire I had in the 1980's.

 

If I remember correctly, the problem was eventually traced to a newly installed set of points. The LT and/or Condenser wiring terminal had been fitted the wrong way round allowing arcing to occur to the distributor casing.

 

I'm a bit hazy on the detail; it was a long time ago....