Whats the best way to check for intake manifold leaks? Im using a performer aluminum intake with an edelbrock carb and im not sure how to check for leaks. The car will not stay running when put in gear but runs fine with no load. PS its a 1964-68 chevy 283 installed in an 83 chevy caprice for my son.
06-17-2012 07:01 PM
Just carburetor cleaner and spray around the edge on the manifold and the base of the carburetor and if the idle changes then you know there is vacuum leak.
06-17-2012 07:10 PM
Spraying is good for an external leak, BUT will not reveal a leak from the crankcase side.
To check that , you need to pull the pcv from its fitting and block the hole with a plug. Then on the vent side plug in a vacuum gauge. It should build a small amount of pressure due to blow by , even on a healthy engine, if the gauge goes into a vacuum, that would indicate an internal leak from the crankcase side.