3.8 rebuild problem - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


General GM Chat When starting new posts, please specify YEAR, MAKE, MODEL, ENGINE type, and whatever modifications you have made. Chat about all things GM (and related cars). Off-topic stuff should be in the Lounge, and all Model specific mechanical problems should be posted in the proper forum.

Reply
 
 
 
Thread Tools Search this Thread
Old 10-03-2011, 08:27 PM   #1
Junior Member
Posts like a Ricer Type-R
Thread Starter
 
FLYNN's Avatar
 
Join Date: Oct 2010
Posts: 10
Thanks: 0
Thanked 0 Times in 0 Posts
FLYNN is on a distinguished road
Default 3.8 rebuild problem

i have recently replaced the lower end new crank berrings lifters and oil pump i am getting a knock at low idle it sounds like lifters not pumped up so i replaced them and the oil pump still hearing the noise any sugestions
FLYNN is offline   Reply With Quote
Old 10-03-2011, 08:37 PM   #2
Retired Senior Admin

Expert Gearhead
 
Danthurs's Avatar
 
Join Date: May 2006
Location: Sheboygan Wisconsin
Posts: 29,661
Thanks: 0
Thanked 16 Times in 13 Posts
Danthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to all
Default

Is the noise on the top or bottom of the engine? Is it there all the time or just when you give it gas or just get off it? Does it sound anything like this?

Attached Thumbnails
3.8 rebuild problem-th_m4h03825.jpg  
Danthurs is offline   Reply With Quote
Old 10-03-2011, 08:48 PM   #3
Junior Member
Posts like a Ricer Type-R
Thread Starter
 
FLYNN's Avatar
 
Join Date: Oct 2010
Posts: 10
Thanks: 0
Thanked 0 Times in 0 Posts
FLYNN is on a distinguished road
Default

its on the top end in the center at idle if u give it 100 rpm more it goes away
FLYNN is offline   Reply With Quote
Old 10-03-2011, 08:49 PM   #4
Junior Member
Posts like a Ricer Type-R
Thread Starter
 
FLYNN's Avatar
 
Join Date: Oct 2010
Posts: 10
Thanks: 0
Thanked 0 Times in 0 Posts
FLYNN is on a distinguished road
Default

no it sounds like lifter tap
FLYNN is offline   Reply With Quote
Old 10-03-2011, 08:54 PM   #5
Junior Member
Posts like a Ricer Type-R
Thread Starter
 
FLYNN's Avatar
 
Join Date: Oct 2010
Posts: 10
Thanks: 0
Thanked 0 Times in 0 Posts
FLYNN is on a distinguished road
Default

i did forget the harmonic balancer went bad
FLYNN is offline   Reply With Quote
Old 10-03-2011, 08:59 PM   #6
Senior Member
Posts like a 4 Banger
 
Join Date: Aug 2011
Location: muskegon, mi
Posts: 131
Thanks: 0
Thanked 0 Times in 0 Posts
pbrktrt is on a distinguished road
Default

Balance shaft perhaps?
pbrktrt is offline   Reply With Quote
Old 10-03-2011, 09:06 PM   #7
Junior Member
Posts like a Ricer Type-R
Thread Starter
 
FLYNN's Avatar
 
Join Date: Oct 2010
Posts: 10
Thanks: 0
Thanked 0 Times in 0 Posts
FLYNN is on a distinguished road
Default

how do u tell if the balance shaft or berrings are bad
FLYNN is offline   Reply With Quote
Old 10-03-2011, 09:11 PM   #8
Retired Senior Admin

Expert Gearhead
 
Danthurs's Avatar
 
Join Date: May 2006
Location: Sheboygan Wisconsin
Posts: 29,661
Thanks: 0
Thanked 16 Times in 13 Posts
Danthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to all
Default

If bearings are bad your oil pressure will drop. Use a stethoscope to track it down. Could be a simple noisy injector.
Danthurs is offline   Reply With Quote
Old 10-03-2011, 09:16 PM   #9
Junior Member
Posts like a Ricer Type-R
Thread Starter
 
FLYNN's Avatar
 
Join Date: Oct 2010
Posts: 10
Thanks: 0
Thanked 0 Times in 0 Posts
FLYNN is on a distinguished road
Default

lower berrings are new balance shaft berrings wernt changed noise is in the center top of engine only at idle
FLYNN is offline   Reply With Quote
Old 10-03-2011, 09:17 PM   #10
Junior Member
Posts like a Ricer Type-R
Thread Starter
 
FLYNN's Avatar
 
Join Date: Oct 2010
Posts: 10
Thanks: 0
Thanked 0 Times in 0 Posts
FLYNN is on a distinguished road
Default

oil presure is 55 60
FLYNN is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Th440/4t60 problem after rebuild Alkemenia Oldsmobile 9 11-21-2011 07:42 PM
Alignment/balance problem after transmission rebuild tumbleweed 1992-1999 0 07-04-2008 04:09 PM
one small problem after tranny rebuild spidey3479 1987-1991 11 11-09-2007 02:09 AM
SUPERCHARGER REBUILD-QUESTION Chris&Stacy Forced Induction 12 10-28-2006 10:11 PM
M62 Supercharger R&R/Rebuild willwren Forced Induction 28 02-16-2003 10:54 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 10:12 AM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.