Name that valve train damage....
Thread Starter
Intermediate
Joined: May 2011
Posts: 29
Likes: 0
Name that valve train damage....
LS3 with full bolt ons, comp 921 kit (push rods, valve stem seals, double springs etc included in this kit), G6X3 cam,.... otherwise stock motor.
found this under the valve covers after started getting a slight misfire at low rpms.... dynoed 475 RWHP initially @ 10 months ago~4000 miles; got it dynoed a few weeks ago and now dynos 415....
im thinking its a valve stem seal... springs coming off Friday to look closer.
found this under the valve covers after started getting a slight misfire at low rpms.... dynoed 475 RWHP initially @ 10 months ago~4000 miles; got it dynoed a few weeks ago and now dynos 415....
im thinking its a valve stem seal... springs coming off Friday to look closer.
_Sloth Whisperer_
Joined: Jul 2008
Posts: 3,369
Likes: 9
From: Malaysia Air Flight 370
Seeing as they're still up in the head and outside of the springs, I would imagine a chewed up rocker arm trunion as well. Seat or lock/seal damage would usually be stuck inside the spring or sucked down into the cylinder, I would think.
But if the rockers are all good as you say, then.... ? Bend a valve and chew up a seat, somehow end up with the valve pulling it up and spitting it out? Weird, but possible I guess.
But if the rockers are all good as you say, then.... ? Bend a valve and chew up a seat, somehow end up with the valve pulling it up and spitting it out? Weird, but possible I guess.
Racer
Joined: Dec 2010
Posts: 418
Likes: 0
From: South Central Kansas
Broken inner valve spring with broken valve seal.
Question? The top piece in picture #2, is it all metal or is it partly rubber. If it is part rubber then you have a broken seal and a busted inner valve spring. If it is all metal then again I think it is part of a keeper. Just a guess, but after looking closley again that is what it looks like. Hard to judge size from the picture.
Question? The top piece in picture #2, is it all metal or is it partly rubber. If it is part rubber then you have a broken seal and a busted inner valve spring. If it is all metal then again I think it is part of a keeper. Just a guess, but after looking closley again that is what it looks like. Hard to judge size from the picture.
Last edited by 1fastbob; Mar 14, 2012 at 07:32 PM.
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Racer
Joined: Dec 2010
Posts: 418
Likes: 0
From: South Central Kansas
The bigger curved pieces..are they big enough to be part of the inner valve spring? Also just a broken valve seal would not have much of an effect on HP so something must have broken it.
Racer
Joined: Dec 2010
Posts: 418
Likes: 0
From: South Central Kansas
Melting Slicks
Joined: Jan 2009
Posts: 2,127
Likes: 33
From: Easley/Anderson South Carolina
If material is stuck between the springs, they wont open completely, meaning there is you possible loss of power? Just a guess. Bigger question is WHY it happened, so you can make sure it doesnt happen again. More pictures when the springs come off is a must!!
Burning Brakes
Joined: Nov 2011
Posts: 795
Likes: 1
From: tacoma wa
If it was me, i would replace all the seals, see how it runs.? then do a leak down test.
It all depends on what he finds under the springs.
