Welcome to the North American Subaru Impreza Owners Club Wednesday August 27, 2014
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Technical > Normally Aspirated Powertrain

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 07-20-2005, 03:39 PM   #1
mikesspeed
Scooby Newbie
 
Member#: 91702
Join Date: Jul 2005
Default 2000 Impreza 2.5RS Rod bearing failure HELP!

Hi very first post on this website so hopefully some you suby savvy people can help me out. It came to us first with a bad engine noise wich sounded like a rod bearing. The owners explained that he was bombing down the highway with the peddle to the mat and all of a sudden started hearing a knocking noise. Low and behold, #2 & #3 rod bearings were badly scored as was the crank. Everything was spec'ed out; crank bearings were spec'ed and ground, new rod bearings from subaru aslo spec'ed before install, erverything was cleaned and double checked and new gaskets. I should also mention that he has cat-back exaust, performance chip, iridium plugs/wires. About two weeks later 1500 kms, he comes back with again bad engine noise wich of course sounds like a rod bearing and again #2 & #3 crank bearing are done. Now before he recieved his car, oil pressure was checked a found to be ok. There are no signs of detonation on the pistons, no heat discoloration on the crank journals or rods. What gives!!! Ive been reading alot lately and have seen this issue resolved with a short block, but to go and buy a short block without knowing for sure the reason for this mess is kinda stupid. Any help is apreciated.
* Registered users of the site do not see these ads.
mikesspeed is offline   Reply With Quote
Old 07-21-2005, 12:47 AM   #2
Storm
Scooby Guru
 
Member#: 5218
Join Date: Mar 2001
Chapter/Region: MWSOC
Location: SAUL'S Motorsports
Vehicle:
96L Most Over-
Developed Beater

Default

There is some mention deep in the archives of different (size) oil passages on the outer 2 rods which may (and have) cause(d) bearing failure on the inner rods at sustained high RPM. It was also attributed with sustained high lateral g loading such as seen in roadracing. More details from your customer may shed more light on the subject.

PM "zzyzx" and ask about what type of bearing failure he ended up with a couple years back. TWE ended up doing the rebuild iirc.....

Jay Storm
Storm is offline   Reply With Quote
Old 09-13-2005, 10:20 AM   #3
ODGC8
Scooby Newbie
 
Member#: 88106
Join Date: May 2005
Location: Buffalo, NY
Vehicle:
2010 2010 legacy GT
Black mica

Default

hey, i dont know if im having the same prob but since you guys have then maybe you can diagnose mine, i posted it on here but i ll repeat it again.....
In the morning when its cool out my engine makes a knocking sound that seems to be coming from the center of the engine somewhere...the sound virtually dissappears when the engine is up to OT.. I also dont get the sound at a constant rpm unless the engine is under a load.. I can produce the sound just by blipping the throttle in the morning or when the engine is cool but at a normal idle there is really no sound... Its definately a knocking sound..... Does this sound like the symtoms of a bad rod bearing to you guys?

owen
ODGC8 is offline   Reply With Quote
Old 09-27-2005, 05:05 PM   #4
John2.5RS
Scooby Guru
 
Member#: 1140
Join Date: Mar 2000
Chapter/Region: SCIC
Location: On the road
Vehicle:
2013 Ecoboost'd F150
Grey

Question

Sounds like oil starvation. You may have some debris in an oil passage. Replace the block.
John2.5RS is offline   Reply With Quote
Old 09-28-2005, 02:04 PM   #5
awesome2.5rs
Scooby Newbie
 
Member#: 96154
Join Date: Sep 2005
Chapter/Region: MWSOC
Location: Beecher, IL
Vehicle:
98 2.5RS
Red

Default

For both of the above situations, I would replace the block. You never know if you are going to have problems in other parts of the block later down the road that are related to this issue. Replace the block and never have to worry about it again. You'll save the hassle of having to do it AGAIN if you replace. (at least in my opinion)
awesome2.5rs is offline   Reply With Quote
Old 09-28-2005, 04:16 PM   #6
Hayes
Scooby Specialist
 
Member#: 11808
Join Date: Oct 2001
Location: Cape Coral,FL
Default

You might also want to check the crankshaft for jounal taper. Another thing to check is rod straightness I.E. wrist pin to jounal but, you really need a surface table, dial indicators and Jo-blocks for this. A new/different block may not solve this problem and I suggest you find the problem before going ahead blind. JMHO. ed
Hayes is offline   Reply With Quote
Reply

Thread Tools
Display Modes

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
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
WTT: WA 2000 Impreza 2.5RS 2-Door CLEAN!!! StealthREX Private Vehicle 'For Sale' Classifieds 36 05-03-2009 11:26 AM
quick! need wheel off-set and lug config for a 2000 impreza 2.5rs wnut Bay Area Impreza Club Forum -- BAIC 3 05-14-2001 11:42 AM
TEC II and 2000 Impreza 2.5RS lo0pback Bay Area Impreza Club Forum -- BAIC 1 02-05-2001 05:06 PM
2000 Impreza 2.5RS Colors cmce New England Impreza Club Forum -- NESIC 1 08-11-2000 06:06 PM
About to buy 2000 Impreza 2.5RS and Parts... CMirza General Forum Archive 3 05-23-2000 11:03 PM


All times are GMT -4. The time now is 03:56 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.