7 replies to this topic

[MaxDempsey]

1989 Mayfair 998cc

 

I have a problem where the engine cuts out whenever I come to a stop. In order to stop this I have to keep my foot lightly on the throttle pedal to keep the revs up. First I thought it was a vacuum leak and decided to to take off the carb and fit new gaskets on the intake manifold. While taking the carb off I noticed play in the throttle spindle and thought there could be a vacuum leak there. The carb has since had new bushes fitted and put back on the car. All the electrics are less than a year old with a new dizzy, coil, leads and plugs. After refitting the carb I still have this problem.

I think it is a fuel problem rather than an electrical problem as when it was happening there was a smell of un burnt fuel.

Has anyone had this issue before?

Thanks

Max

Edited by MaxDempsey, 04 January 2016 - 10:02 AM.

[cal844]

Yes, turn the fuelling up slightly

[jb93]

Is the dashpot oil topped up?

[MaxDempsey]

The dashpot has oil

By the turn the fuelling up do you mean adjust the mixture to run richer?

[Carlos W]

What does it tick over at normally?

[MaxDempsey]

When it doesnt cut out the idle was around 1000 rpm. The problem was intermittent but when it happened it was constant for the journey, then sometimes it would be fine. I also had the mixture set without a rolling road by a garage so at idle/fast idle it was running right 

[Cooperman]

Does the carb piston drop cleanly and quickly to the bottom with an audible 'click' when lifted right to the top with a finger and let go. If the piston does not drop fully and quickly the engine may run momentarily too rich which can cause a fuel small and stalling. It will then start straight away as the piston will finally 'touch down' and the starting mixture will again be correct.

Piston not dropping can be a mis-aligned needle of the piston scraping on the dashpot.

[MaxDempsey]

When the carb was off the car the piston did drop with a click. It also had a new jet and needle while off the car but the problem has not been made worse or better

I'll take off the air filter and lift the piston ad re check this. It has a swinging needle so should align itself I thought (this is my first time trying to work on a carb so I'm not 100% clear :) )

Edited by MaxDempsey, 04 January 2016 - 02:42 PM.