Vaccum Leaks

[nealf]

How do I safely check for vaccum leaks? I thought around the base of the carb and/or manifold could be a possible area. Also, what vaccum lines may be a problem? My motor does not want to idle and thought I would check there areas first as there have been no other changes recently. Thanks.

nf
'70 2800-front carb running rich
'73 2002-never any car issues

 

[corsachili]

A quick and easy method is to buy a can of Berryman's carb cleaner. With the engine running spray it around all suspect joints and gasket mating surfaces. If you hear the engine increase in speed, you've found a leak.

 

[Honolulu]

leak finding

there are several ways....

first and always, use your eyes to inspect all vacuum connections. Look at all hoses, they tend to crack/leak near connections.

you can use a bit of tubing with one end in your ear as a stethescope.

you can dribble water around suspect areas while the engine is running, a leak will suck in water which will cause the idle speed to drop

you can use carb cleaner, propane or other flammable liquds or gases to find leaks, the idle speed will rise. Caution... flammable liquids/gases.... use at your own risk