Testing Intake Manifold Gaskets with Smoke Machine
Thread Starter
On The Tree
Joined: Apr 2013
Posts: 179
Likes: 0
From: Utica, IL
Testing Intake Manifold Gaskets with Smoke Machine I have a few thousand miles on my most recent build. It runs good but uses some oil and blows some smoke out the exhaust when I get on it pretty hard. I am thinking either the intake did not seal completely internally or the rings did not seat right. My block is zero decked and heads have been milled by Lloyd so I had to have the intake rails milled to get it to fit. It was pretty far off.
I bought a cheapish smoke tester that puts out 1 psi of smoke and actually works pretty good. I disconnected the PCV system and plugged the tester into the passenger side valve cover to pressurize the crankcase with smoke. When I open the throttle blades I get a slight amount of smoke coming out of the throttle body. Would this indicate that my intake is not completely sealed or am I missing something?
My other option is to do a compression test and leak down test, but I figure I would probably have to pull the headers (which is a PITA) to access all the cylinders with the testers. The spark plugs are a tight fit in a few spots. Thanks for any input!
I bought a cheapish smoke tester that puts out 1 psi of smoke and actually works pretty good. I disconnected the PCV system and plugged the tester into the passenger side valve cover to pressurize the crankcase with smoke. When I open the throttle blades I get a slight amount of smoke coming out of the throttle body. Would this indicate that my intake is not completely sealed or am I missing something?
My other option is to do a compression test and leak down test, but I figure I would probably have to pull the headers (which is a PITA) to access all the cylinders with the testers. The spark plugs are a tight fit in a few spots. Thanks for any input!
TECH Veteran
Joined: Apr 2008
Posts: 4,985
Likes: 112
get a can of starter fluid spray and spray around intake with engine running and if RPM spikes when you get to a particular spot...that's your leak
Be mindful of hot exhaust while spraying...it just takes a little spray
Be mindful of hot exhaust while spraying...it just takes a little spray
