# Leak Down Test **URL:** \ **Category:** Shift518 Automotive\ **Created:** [October 28, 2008, 3:41pm UTC](https://forums.speedlife.net/t/leak-down-test/239839 "2008-10-28T15:41:14Z")\ **Posts on this page:** 5\ **Page:** 2
**Author:** ![99SC286](https://avatars.discourse-cdn.com/v4/letter/9/a87d85/32.png) [@99SC286](https://forums.speedlife.net/u/99SC286)\ **Post date:** [November 1, 2008, 9:01am UTC](https://forums.speedlife.net/t/leak-down-test/239839/21 "2008-11-01T09:01:52Z")
> [@Boxersix](#): > > If you’re head gasket is leaking it will yield useless results. A LD test will not decipher what the issue is, it just informs you the sealing condition of the cylinder(s) in question. You should just pull the head and get things repaired if the gasket is leaking. Driving on a blown gasket will only make things worse in a multitude of ways, including permanent damage to the head that cannot be repaired(cost effectively that is). If you pull the head and have it completely gone through(typically 2-250 per 4cyl head head here) and install a new gasket, THEN do a leakdown test your results will show you the sealing condition of the existing rings and new valve grind. I’ve got two pallets worth of stacked 420a core heads here at the shop, they’re known for issues to say the least. > > If it’s buring oil: > > Smoke on decel usually indicates worn valve guides and/or stem seals > Smoke under accel usually indicates worn rings, wall scoring, excessive cylinder taper, etc, etc > > faulty pcv system can yield smoke as well pending motor condition and system setup. > > Just things to consider here that’s all… do you have a head thats been all redone? I’m trying to spend as little money as possible on this thing until i can sell my truck. I had called NAPA machine shop a couple weeks ago, and they want about 400 to change valve seals and guides. ---
**Author:** ![Vandal](https://avatars.discourse-cdn.com/v4/letter/v/858c86/32.png) [@Vandal](https://forums.speedlife.net/u/Vandal)\ **Post date:** [November 1, 2008, 2:14pm UTC](https://forums.speedlife.net/t/leak-down-test/239839/22 "2008-11-01T14:14:02Z")
> [@94 Sentra\_Xe](#): > > this is my brothers car, it is a 1995 mitsubishi eclipse with a 2.0 DOHC IMO it sounds like valve stem seals, they are notorious in the 420A. My old Talon did that every time I was at a light or pulling away after idling. ---
**Author:** ![Boxersix](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/boxersix/32/6327_2.png) [@Boxersix](https://forums.speedlife.net/u/Boxersix)\ **Post date:** [November 1, 2008, 4:59pm UTC](https://forums.speedlife.net/t/leak-down-test/239839/23 "2008-11-01T16:59:26Z")
> [@99SC286](#): > > do you have a head thats been all redone? I’m trying to spend as little money as possible on this thing until i can sell my truck. I had called NAPA machine shop a couple weeks ago, and they want about 400 to change valve seals and guides. No, just cores… Most are sans valve train. I keep them in the event that a head is shot from a customer and non-repairable. There’s no reason to change guides unless they’re bad. Guides should also not be replaced without doing a valve job. It’s just tossing money into the wind. If you can pull the head, bring it to the machine shop and talk to Dave or Shawn about scheduling and going through the head. I’ve got a lot on my plate at the moment and will not be able to do it myself. ---
**Author:** ![99SC286](https://avatars.discourse-cdn.com/v4/letter/9/a87d85/32.png) [@99SC286](https://forums.speedlife.net/u/99SC286)\ **Post date:** [November 1, 2008, 7:11pm UTC](https://forums.speedlife.net/t/leak-down-test/239839/24 "2008-11-01T19:11:59Z")
do you know what it would cost roughly? I have the head installation gasket set, which is the gasket and valve seals, and i dk if anything else i haven’t opened the box. I didn’t want them to get ruined before i used them ---
**Author:** ![88slowmarro](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/88slowmarro/32/6339_2.png) [@88slowmarro](https://forums.speedlife.net/u/88slowmarro)\ **Post date:** [November 1, 2008, 7:16pm UTC](https://forums.speedlife.net/t/leak-down-test/239839/25 "2008-11-01T19:16:36Z")
if ya dont know a ton about cars dont attempt it yourself ,things get confusing quik and if ya dont know how to set timing marks trq diagrams and other shit take it somewhere it will be cheaper in the long run :nod as opposed to ruining a motor [Previous page](https://forums.speedlife.net/t/leak-down-test/239839.md?page=1)