Top end knock 98 LS1
10-26-2011, 01:25 PM
#1
Teching In
Thread Starter
iTrader: (3)
Join Date: Jun 2009
Location: Florence, Al
Posts: 11
Likes: 0
Received 0 Likes
on
0 Posts
Top end knock 98 LS1 Car only knock at 2.5k+, knock goes up with rpms. I pulled the driver side valve cover and had 2 broken rocker arms, replaced them and checked the push rods but they aren't bent.. What do? Knock still exists and is coming from the top end.
10-26-2011, 01:42 PM
#2
TECH Enthusiast
iTrader: (7)
Join Date: Jan 2011
Location: Longbeach, CA
Posts: 590
Likes: 0
Received 0 Likes
on
0 Posts
Got a video of the sound it's making? My car has a lot of knocking/clicking/ticking from the top end. I just ignore it. Sounds like yours is probably worse if you're finding broken components.
10-26-2011, 02:09 PM
#3
On The Tree
Join Date: May 2011
Location: Phoenix AZ
Posts: 146
Likes: 0
Received 0 Likes
on
0 Posts
I'm having a similar issue with my truck right now but I'm coming to the conclusion that i have an oil pump or oil pump o ring failure that is causing not enough oil to flow into the valvetrain (20 psi) and it's real jittery at that.
is the oil gauge bouncing around by chance?
https://ls1tech.com/forums/generatio...ed-lifter.html
is the oil gauge bouncing around by chance?
https://ls1tech.com/forums/generatio...ed-lifter.html
10-26-2011, 03:20 PM
#4
Teching In
Thread Starter
iTrader: (3)
Join Date: Jun 2009
Location: Florence, Al
Posts: 11
Likes: 0
Received 0 Likes
on
0 Posts
I'm having a similar issue with my truck right now but I'm coming to the conclusion that i have an oil pump or oil pump o ring failure that is causing not enough oil to flow into the valvetrain (20 psi) and it's real jittery at that.
is the oil gauge bouncing around by chance?
https://ls1tech.com/forums/generatio...ed-lifter.html
is the oil gauge bouncing around by chance?
https://ls1tech.com/forums/generatio...ed-lifter.html
10-26-2011, 04:26 PM
#5
TECH Resident
I had a wierd noise from my car after a session of spirited driving, turns out it was a stuck lifter. Is the noise a fast noise or a slow one. According to my mechanic a fast noise indicates top end, rocker,lifter,rocker arm. Slow could be a bearing or wrist pin. Try pulling a spark plug wire at a time to see if you can isolate the sound. If it goes away when the power is killed on the cylinder then you can isolate the problem with minimal tear down. Good luck!!!
10-26-2011, 04:32 PM
#6
Teching In
Thread Starter
iTrader: (3)
Join Date: Jun 2009
Location: Florence, Al
Posts: 11
Likes: 0
Received 0 Likes
on
0 Posts
I had a wierd noise from my car after a session of spirited driving, turns out it was a stuck lifter. Is the noise a fast noise or a slow one. According to my mechanic a fast noise indicates top end, rocker,lifter,rocker arm. Slow could be a bearing or wrist pin. Try pulling a spark plug wire at a time to see if you can isolate the sound. If it goes away when the power is killed on the cylinder then you can isolate the problem with minimal tear down. Good luck!!!
