Rough running and carbs flooding

[timdaw]

Thanks Alan and others for suggestions. I don't have a pressure gauge to test the pump but when I tried it again today, it ran rough, then when I undid one of the fuel banjo's after switching off, the petrol sprayed out quite impressively, so I think it is the pump. I'm trying to locate a glass top pump to rebuild.

[nmauduit]

Actually, Alan, it doesn't have the glass dome. So it's clearly a replacement. The car was running very well before this happened, so I'm at a loss. Why would it suddenly have it's pressure increased?

if the car was running very well no so long ago, it's unlikely that the mechanical pump is totally incompatible with the car... did you check the carbs float needle valves (blowing through via the carb is not as reliable as a pressure test, but might give an insight of a leaky one - in situ cuve fuel level check would be an other check) ? the pump needs to send some fuel so that the engine does not starve at full throttle, I would not deem it to be changed just from your description of squirting at the hose...

[alan.barker]

At full throttle you need flow rate not to be confused with pressure.
Flow and pressure are not the same thing.
Alan

[Craven]

At full throttle you need flow rate not to be confused with pressure.
Flow and pressure are not the same thing.
Alan

Not the same but,
The flow rate is proportional to the square root of the pressure gradient (F ∝ √P)

[alan.barker]

as they say no buts lol
Alan

[alaric]

Courtesy of Bernoulli I believe.

[TBG]

Ah - memories - if you stand with your back to the wind in the northern hemisphere the low pressure is on your left - and your bum is always behind you..................D

[alaric]

Brilliant. So would that be due to the Coriolis force?

[alan.barker]

Mmm could that be something to do with the "trade winds".
Alan

[2cams70]

I'm not sure where all this discussion is headed but it does seem as though there's a lot of lentil eating vegetarians with wind problems in the Northern Hemisphere.

[JohnMorin]

Hi

I changed to an electric pump recently so I have an original glass dome pump in bits if you want it, it will need a rebuild though. I made the change because this one of the only components that's given me problems on more than one occasion.

John