Welcome, Guest. Please login or register.
November 23, 2008, 10:44:00 AM

Login with username, password and session length

Visit ReillyMotorSports
* Home Help Search Memberlist gallery Login Register
+  The BigBlockDart Message Board
|-+  Technical
| |-+  Engine, Drivetrain
| | |-+  vacuum leak?
Pages: [1] Go Down Print
Author Topic: vacuum leak?  (Read 89 times)
3404bbl
Jr. Member
**
Offline Offline

Posts: 59

BigBlockDart.Com


vacuum leak?
« on: July 16, 2008, 11:29:53 PM »

I've got a stock 360 with a cast iron 4 barrell manifold. It idles pretty rough. I noticed some oil around one of the center intake bolts. I don't have a vacuum gauge, but I'm thinking that may be my problem. It's a new rebuild.

Thoughts? Should I just go ahead an dput new gaskets on it?
Logged
NYrr496
BBD God
*****
Offline Offline

Posts: 3771

Long Island, NY


Re: vacuum leak?
« Reply #1 on: July 16, 2008, 11:35:38 PM »

I would certainly take it apart carefully and see if it's drawing oil from the mating surface down an intake port. I don't know that I've ever seen oil come up an intake bolt.
Logged

It takes a Mopar to catch a Mopar.
MVRCorp
BBD God
*****
Offline Offline

Posts: 1699

BigBlockDart.Com


Email
Re: vacuum leak?
« Reply #2 on: July 16, 2008, 11:41:08 PM »

Get a can of WD-40 or engine cleaner and let the engine idle. Spray around all the mating surfaces including the carb base. When you here an RPM change you have located the leak. No RPM change, no vacuum leak. Simple check.  Grin
Logged

IF YOU CAN'T FIX IT WITH A HAMMER YOU HAVE AN ELECTRICAL PROBLEM.
67dartgt
Full Member
***
Offline Offline

Posts: 355

BigBlockDart.Com


Re: vacuum leak?
« Reply #3 on: July 16, 2008, 11:51:14 PM »

I would certainly take it apart carefully and see if it's drawing oil from the mating surface down an intake port. I don't know that I've ever seen oil come up an intake bolt.

I have! A stock 318 with an aluminum 4 barrel manifold. I saw someone somewhere seal the threads on the center intake bolts so that it doesn't happen. But it would puddle at the bottom of my intake from the center bolts.

- Don
Logged
67dartgt
Full Member
***
Offline Offline

Posts: 355

BigBlockDart.Com


Re: vacuum leak?
« Reply #4 on: July 16, 2008, 11:52:14 PM »

PS. Not to say that sealing the threads is the right way. i didn't do that. But my leak didn't affect the idle. My idle problems were an overcarb'ed 318 with a single plane manifold.  taunt
Logged
Pages: [1] Go Up Print 
Jump to:  

Powered by MySQL Powered by PHP The BigBlockDart Message Board | Powered by SMF 1.0.5.
© 2001-2005, Lewis Media. All Rights Reserved.
Valid XHTML 1.0! Valid CSS!