Re: alfa-digest V7 #104

[richard bies <bies@xxxxxxxxxxxxxxxxxxx>]

> 
> Another query please.......
> On your typical Alfa Romeo 4-cyl twin cam with its dual
> sidedraught Webers or Dellortos, I wonder if anyone can suggest
> how one would go about checking for a possible vacuum leak
> around the undersides of the carb mounting rubbers, inlet
> manifold or gasket ?   
> I believe that to check for vacuum leaks in general, there's a
> variety of methods (involving spraying CRC or somesuch over the
> target area, or painting on detergent, etc), but there seems to be
> insufficient access to the undersides of the carbs and manifold to
> use any of these satisfactorily....... does anyone have any
> comments please?
> (Not that I do have any suspected vac leak problem right now.....
> but I did want to make such a check once some time ago, and I
> was stuck as to how to access that area in order to check around
> there).
>  
The potion I find useful is the spray-can of ether (marketed as "Sure
Start" or something like it -- an aid to get the engine to fire).

With the air-intake plumbing in place and the engine at idle, if a short
blast of this spray at the carbs results in a pick-up in engine speed,
there is a leak.  Isolating <where> is a matter of short, targeted blasts
and interpretation.  There is no digital read-out of exactly where the
leak is.

r.m.bies

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