Re: Vacuum leak at throttle plate shaft

["David Teitelbaum" <jtrealty@xxxx>]

There is a better way to find small vacuum leaks. This is an old
mechanic's trick and is to be used cautiously.
Hook up a tach meter so you can watch the engine RPM's. Next get a
Burnsomatic torch (the kind with the disposable propane bottle that is
used for plumbing), remove the tip and slid a short piece of hose over
the pipe. Now aim the hose at a suspected leak, crack open the valve
for a second and watch the tach. If you see a change in RPM's then you
are near a leak. This MUST be done carefully as propane is highly
flammable. Any sparks (like from bad ignition wires) can set the
propane on fire. This will find the smallest leaks and help you
pinpoint them. I think this is safer than using carb cleaner as this
is a gaseous mixture as opposed to a liquid so it dissapates more
quickly. It also has a more immediate effect on the idle. Ether
(starting fluid) can also be used but is also dangerous and harder to
control with an aerosol can. From all that has been posted about
vacuum leaks the best bet is to just inspect and/or replace all
gaskets, seals, and hoses. This procedure is meant to find something
unusual after having gone over everything and still having problems. 
David Teitelbaum
vin 10757


--- In dmcnews@xxxxxxxxxxxxxxx, "content22207" <brobertson@xxxx> wrote:
> Even carburetors will eventually start to leak there. Problem is steel
> shaft rotating in a softer metal. Mine sucks a little, but not enough
> yet to cause real problems. Will watch as car ages.
>