Intake Man. Vac leak-Tips?

[AaronB]

I have a vacuum leak in the intake manifold of my 94GrandCherokee. I was told by a mechanic that this isn't too tough of a job. We'll see. Apparently must drain coolant, replace a gasket. Not much advice in my Chiltons. Any tips out there to see this go smoothly?
Thanks

 

[Snitty]

what motor is it... likely won't have to drain coolant

 

[jeepin916]

huh? drain coolant? what engine? V8? dont think there is any coolant involved with the intake manifold unless its the V8 and its got a cross over built into the intake that feeds the heads, that still seems unlikly, not too many car manufactures do that any more

 

[AaronB]

it is the V8- 5.2L high output MPI engine. So, the only reason to drain coolant is if there is some time of coolant flow through or around the manifold? How do I find out for sure if there is, or should I just drain it to be sure? Thanks again

 

[Bounty__Hunter]

Just drain the radiator, that'll get coolant level below the intake manifold, and it's easy.

Where did they tell you the vacuum leak is? There's so many other possibilities (and more likely) besides the intake manifold gasket.

 

[jeepin916]

hey check for your self where the vacuum leak is, go buy urself a can of brake cleaner and spray it around where the gaskets are, if your idle goes up then your close. dont spray like crazy a slight squirt will make the idle jump, i cant see how the intake is leaking unless its a really old motor the intakes been taken off once manifold gaskets dont really go bad that easily...

 

[Bounty__Hunter]

Another trick is to use an unlit LP bottle like what plumbers use to sweat pipes. Just don't go near the airbox.