LT1 Based Engine Tech 1993-1997 LT1/LT4 Engine Related

95 z28 camaro rebuilt lt1 noise issues

Thread Tools
 
Search this Thread
 
Old 04-28-2018, 08:34 PM
  #1  
Registered User
Thread Starter
 
Humblelt1's Avatar
 
Join Date: Apr 2018
Posts: 17
95 z28 camaro rebuilt lt1 noise issues

Hi im new to the forums. i got a rebuilt lt1 in a 95 z28 cc503, scorpion rockers 1.5 rebuilt bottom end. but it makes noise and i can't figure out what it is. will upload video. Sorry for not posting in lt1 tech

Last edited by Humblelt1; 04-28-2018 at 08:53 PM. Reason: Miss posting
Humblelt1 is offline  
Old 04-30-2018, 12:24 PM
  #2  
Registered User
 
DrewHMS97SS's Avatar
 
Join Date: Sep 2003
Location: Las Vegas
Posts: 1,916
Re: 95 z28 camaro rebuilt lt1 noise issues

That sounds like a loose rocker to me. Have you pulled the valve cover and checked the rocker adjustment?
DrewHMS97SS is offline  
Old 04-30-2018, 02:37 PM
  #3  
Registered User
 
Chimera96's Avatar
 
Join Date: Jun 2003
Posts: 1,083
Re: 95 z28 camaro rebuilt lt1 noise issues

OP

did you trim the braces on the Valve Covers for the roller rockers?

if not you need to (intake side)....if you did than the valve lash sounds really off
Attached Thumbnails 95 z28 camaro rebuilt lt1 noise issues-valve_c_mod-intake-side.jpg  
Chimera96 is offline  
Old 05-01-2018, 01:42 PM
  #4  
Registered User
Thread Starter
 
Humblelt1's Avatar
 
Join Date: Apr 2018
Posts: 17
Re: 95 z28 camaro rebuilt lt1 noise issues

I adjusted the rockers poly locks. Hand tight then 1/8th to 1/4 turn. And yes I did trim the valve covers. New clutch even ran without valve covers. Still makes the noise.
Humblelt1 is offline  
Old 05-01-2018, 02:31 PM
  #5  
Registered User
 
DrewHMS97SS's Avatar
 
Join Date: Sep 2003
Location: Las Vegas
Posts: 1,916
Re: 95 z28 camaro rebuilt lt1 noise issues

I know some lifters require a bit of different adjustment, do you know what lifters are installed?
DrewHMS97SS is offline  
Old 05-01-2018, 04:44 PM
  #6  
Registered User
 
Chimera96's Avatar
 
Join Date: Jun 2003
Posts: 1,083
Re: 95 z28 camaro rebuilt lt1 noise issues

OP

if that noise is not from anything hitting VC...the valve lash is WAY off.

what method are you using to adjust valve lash?

when you do have the lifter of the particular cyl/valve you are working on sitting on base circle of cam you just tighten polly nut with fingers just till it touches/stops with the very slightest of effort. That is zero lash. If you have regular lifters you then turn 1/2 to 3/4 more turn (preload) then tighten the alan screw while holding poly nut in place. Repeat for each valve

If you have short travel lifters like Comp 875's you only tighten Ploy 1/8 turn MAX
Chimera96 is offline  
Old 05-01-2018, 08:58 PM
  #7  
Registered User
 
shoebox's Avatar
 
Join Date: Dec 1969
Location: Little Rock, AR
Posts: 27,709
Re: 95 z28 camaro rebuilt lt1 noise issues

Sounds like a rod bearing to me.
shoebox is offline  
Old 05-01-2018, 09:16 PM
  #8  
Registered User
Thread Starter
 
Humblelt1's Avatar
 
Join Date: Apr 2018
Posts: 17
Re: 95 z28 camaro rebuilt lt1 noise issues

They are scorpion rockers. So I’m not really sure what lifters are in the motor but I’m assuming comps cause the cam is comp cam 503. I assume I understand hand tighten rocker then tighten poly locks with less then 1/8th pre load? I thought just being to tight would cause loss of compression not valve train noise?
Humblelt1 is offline  
Old 05-01-2018, 09:30 PM
  #9  
Registered User
 
Chimera96's Avatar
 
Join Date: Jun 2003
Posts: 1,083
Re: 95 z28 camaro rebuilt lt1 noise issues

how are you determining the valve you are lashing, that lifter is on the base circle of cam?
Chimera96 is offline  
Old 05-02-2018, 07:47 AM
  #10  
Registered User
Thread Starter
 
Humblelt1's Avatar
 
Join Date: Apr 2018
Posts: 17
Re: 95 z28 camaro rebuilt lt1 noise issues

Sorry basically make sure Intake valve is open then do the exhaust valve lash. And repeat on rest of cylinders. Am I doing that correct? Also shoebox I hope your wrong but there is no metal in the oil besides break in in. But just to be certain as well I’m probably going to be pulling the oil pan this weekend.

Last edited by Humblelt1; 05-02-2018 at 08:03 AM.
Humblelt1 is offline  
Old 05-02-2018, 10:13 AM
  #11  
Registered User
 
DrewHMS97SS's Avatar
 
Join Date: Sep 2003
Location: Las Vegas
Posts: 1,916
Re: 95 z28 camaro rebuilt lt1 noise issues

It is hard to say without knowing the lifter. The Comp R lifters are supposed be adjusted to zero lash, but in their documentation the guide states you need to reference the lifter to find the correct pre-load: COMP Cams® - Lifter Technical Reference
DrewHMS97SS is offline  
Old 05-02-2018, 10:24 AM
  #12  
Registered User
 
Chimera96's Avatar
 
Join Date: Jun 2003
Posts: 1,083
Re: 95 z28 camaro rebuilt lt1 noise issues

OP

if you are doing the EOIC lash method correctly than the valve train should not sound like that...assuming you did lash correctly...you have some serious metal to metal contact going on inside the engine

Video just sounds like serious valve lash issue or RR hitting the valve covers or something in rotating assembly hitting something

Any of the above will kill the motor quickly
Chimera96 is offline  
Old 05-02-2018, 10:28 AM
  #13  
Registered User
 
DrewHMS97SS's Avatar
 
Join Date: Sep 2003
Location: Las Vegas
Posts: 1,916
Re: 95 z28 camaro rebuilt lt1 noise issues

Originally Posted by Chimera96
OP

if you are doing the EOIC lash method correctly than the valve train should not sound like that...assuming you did lash correctly...you have some serious metal to metal contact going on inside the engine

Video just sounds like serious valve lash issue or RR hitting the valve covers or something in rotating assembly hitting something

Any of the above will kill the motor quickly
Does it sound to you from the video that the noise is more predominant from the passenger side though? Wouldn't that point more to something with the rockers/lifters?
DrewHMS97SS is offline  
Old 05-02-2018, 01:15 PM
  #14  
Registered User
Thread Starter
 
Humblelt1's Avatar
 
Join Date: Apr 2018
Posts: 17
Re: 95 z28 camaro rebuilt lt1 noise issues

Yes it is dominant on the passenger side. I’m going to try and get a video later to day of what it sounds like warmed up. It knocks then pauses it strange.
Humblelt1 is offline  
Old 05-02-2018, 02:01 PM
  #15  
Registered User
 
Chimera96's Avatar
 
Join Date: Jun 2003
Posts: 1,083
Re: 95 z28 camaro rebuilt lt1 noise issues

OP

have you taken the valve covers off and looked for any signs of witness marks?

The noise sounds like valve train...but its a cell phone video on the internet
Chimera96 is offline  


Quick Reply: 95 z28 camaro rebuilt lt1 noise issues



All times are GMT -5. The time now is 09:53 AM.