I have an MGB (1800cc) with the same carbs, basically, and have have none of
the problems you mention. The carbs seem well matched to the car, and run well.
do you have the right oil in the dampener chamber? is the piston sticky at
all? are the needles correctly matched to the jets? There were different
diameter jets available for that carb, I think. (.090 and .100, as memory
serves). If you had a needle designed for the smaller jet working with a
bigger jet, it might be too rich at idle.
That's all I can think of,
Brian
At 01:30 AM 5/9/98 -0400, you wrote:
>Malcolm Cox wrote:
>>
>> I have a 1622 MGA, with a pair of 1.75" HS6 SU (originally from a Volvo
>> I believe). Perhaps this problem will strike a chord with someones
>> experience.
>>
>> The problem is that when the engine is switched off, if the float
>> chambers have not been first dried out by idling with fuel pump off, it
>> will not immediately restart unless a carburettor slide is first
>> manually lifted. If left (wet) for 20-30 minutes it restarts easily.
>> This pattern is valid at any engine temp from dead cold to screaming
>> hot.
>>
> Malcolm,
> I could be way off beam here, but I think your problem
> might be that the carbs are too BIG. The 1.75" HS6 is
> a pretty big carb and a pair of them will very happily
> feed a 3 litre engine.... let alone 1600cc.
>
> If you went down to 1.5" you would dramatically increase
> the gas speed through the venturi. I've come across
> situations similar to yours and going back to the original
> carbs solved the problem.
> Faster air flow > better atomisation > no puddling of fuel
> (which you appear to have, from the die spot you found
> inside the intake manifold). Facet pumps, Grosse jets and
> fuel return rails won't help. Less gas to stick things up WILL.
> Give it a try. And remember, you've got to lean to be mean!
>
> MHD
> Auckland
>
>
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