Poor cold starting/empty float chamber?

[captain Byrne]

Hi all, I have a 1.9 DG with a pierburg carb. My problem is poor cold starting. It's ok if it's just been rested for a couple of days but any longer and it takes an age to start. I think I've narrowed it down to a fuel problem or at least I think I have. I checked the float chamber on the carb after it had been stood for a week or so & found very little petrol in it, less than 1 cm. The needle and float are fine and when it does run I have no issues whatsoever & the van runs really well. My question: Is there anywhere the petrol may be draining or leaking from at the bottom of the chamber? Any ideas anyone. Thanks.

[ghost123uk]

I have never actually measured it but I reckon by the time you take the float out of the chamber, the volume of the float (and therefore the remaining area in the chamber) is such that maybe 1cm of petrol is all there would be with no float in place.

I take it the choke assembly is working correctly ?

Either way if you were to do a test like this =

Engine has been stood for a while (long enough to cause your problem)
Remove pipe from pump (the one that feeds the carb)
Use a funnel or similar to manually fill the float chamber to max.
E D I T = (or simply put the feed pipe into a plastic bottle and crank the engine to check the pump is supplying fuel to the carb at a decent rate)
Attempt to start the engine (Don't set yourself on fire with petrol splashing about )
If it starts you are right in your assumption (and could be a weak fuel pump - not fun-heard of)
If it does not start, look at the choke or the quality of the sparks.

Let us know how it goes...

[captain Byrne]

I've just had tried the above suggestion. I left it standing for a few days, checked the float chamber & it was more or less empty. I then filled it with petrol & hey presto it fired up first time. Petrol must be leaking from the chamber somewhere but I haven't a clue where from. Help anyone? thanks.

[ermie571]

Is it evaporating rather than leaking??

ie a seal or gaskget gone?

Just a guess? But there is not a huge amount of petrol in the float chamber....and its taking days (and nights) to empty.

Em
xx