what can an auto shop do that i cant to find a vacuum leak?

on my 305 tpi theres so many wires and hoses in the way im not sure how I could possibly find a stupid vacuum leak because its most likely not in an obvious place

can I rent a vacuum tool that will tell me where the leak is?

or does a shop have specil equipment to save me the agrivation?

 

You can get either a can of carb cleaner, or one of those small propane torches, and spray around different seals. For the propane torch, obviously don't light it, just open the valve so a little propane can come out, and hold it close to intake gaskets, vacuum lines, etc. Carb cleaner with the straw on the tip works well too. If you spray a spot and the engine revs up a little, then you've found the leak.

 

I've found that a carb cleaner with a high naptha content works the best. I've never had good luck with propane. I even tried MAPP to no avail.

 

A squirt bottle with water will work too and it's safer than flammable items. You can also place 1 end of a vacuum line in your ear and probe the gasket surfaces with the other end to listen for a leak.

Try squezzing the vac lines shut with smooth jawed pliers and listen for rpm changes. Don't forget the power brake vacuum line and PCV hose.

Remove the pcv valve and breather tube from the valve covers. Place palms of hands over the holes tightly (best done on cool eng) and see if a vacuum starts building in the crankcase with eng idling. This will indicate an internal vacuum leak, which is pretty rare but can happen if intake gasket leaks on the bottom side.

 

what do u mena if intake leaks on bottom side?

 

Intake manifold gasket. The bottom of those gaskets are right above the oil valley.

 

 

kay guys, i just replaced my 5.7 tpiengine with a crate motor, after putting it in, i believe there is now a vacum leak that causes it to bog out at idle only, when fuel is supplied, it runs great, but i must have my foot on the gas at idle/stop, and i was wondering if anyone knows where i can get a full vacum diagram etc. I have already done the carb/choke cleaner, and found no leaks. I adjusted the timing, but it still bogs out what do i do!!!!??
?

 

Yeah hey man im having the same problem. what i have done but i wanna fix it right. i just create a small vacuum leak on the vacuum hose and it stops dieing when i start it with out gas. but i know its not right but it works. i was hoping if someone comes up with a solution let me know.