Welcome to Bimmerfest -- The #1 Online Community for BMW related information! Please enjoy the discussion forums below and share your experiences with the 200,000 current, new and past BMW owners. The forums are broken out by car model and into other special interest sections such as BMW European Delivery and a special forum to voice your questions to the many BMW dealers on the site to assist our members!

Please follow the links below to help get you started!

Go Back   Bimmerfest - BMW Forums > BMW Model Discussions > M Series

M Series
The ///M Series Forums. If you would like to see all new posts in all the forums, click here.

 
 
Thread Tools Display Modes
  #1  
Old 05-27-2003, 07:28 AM
Jetfire's Avatar
Jetfire Jetfire is offline
Car Junkie
Location: N. VA
 
Join Date: Jun 2002
Posts: 3,397
Mein Auto: '88 M3, Ex-'99 M3
S14 Bearing Pics

http://www.blairlee.com/m3files/bearings/index.html

I'm not quite done with the procedure. The new bearings are all in, but the oil pans have not yet been reinstalled.

No chunks were found in the lower oil pan, and on first inspection nothing looked seriously wrong with the conrods.

Bearings on cylinders 1, 2, and 3 were all in reasonably good shape. Crank journals for those cylinders are also nice and shiny. Bearing clearance (measured with plastigage) was acceptable.

Bearings on cylinder 4 were not fractured, but they're definitely trashed. Down to the copper on almost the entire inner surface. Crank journal is not mirror smooth; some scoring can be felt with my fingernail. Plastigage shows that roughly half of the journal has .001" to .0015" clearance, but the scored side is closer to .002". Not great news.

I'm not experienced in these matters. Is my crank now toast? I can't imagine that it will last all that long. In the short term, I think the new bearings will keep the engine going...but I wouldn't trust the bearings to hold up past this season. And of course, any metal flakes from disintegrating bearings have the chance of getting past the filter and into the engine. Hasn't happened yet but you never know. Any expert opinions on this matter?
__________________

'88 M3
Conforti chip, Evo airbox/K&N filter, UUC short shift kit, oil pan baffle, Hella H4 lights, OEM glass sunroof
sold: '99 M3 Coupe
Cosmos Black
Airbox baffle removed, ZKW ellipsoid headlights, UUC short shift kit, BMW x-brace, debadged

'96 Jeep Grand Cherokee Laredo V8
(Support Vehicle)
Ads by Google
  #2  
Old 05-27-2003, 07:40 AM
bren's Avatar
bren bren is offline
///Mpty pockets
Location: MD
 
Join Date: Jul 2002
Posts: 1,963
Mein Auto: wankermatic
At least they didn' t look like this:



Although I don't think you would be in a much different place if they had....
  #3  
Old 05-27-2003, 07:49 AM
Jetfire's Avatar
Jetfire Jetfire is offline
Car Junkie
Location: N. VA
 
Join Date: Jun 2002
Posts: 3,397
Mein Auto: '88 M3, Ex-'99 M3
Preliminary replies to my posts on other mailing lists suggest that my other bearings were pretty much toast as well. The bearings should really have NO wear on them at all. They're supposed to be separated from the crank by a film of oil, so ideally there should be no contact whatsoever. And the journal on #4 is definitely in bad shape.
__________________

'88 M3
Conforti chip, Evo airbox/K&N filter, UUC short shift kit, oil pan baffle, Hella H4 lights, OEM glass sunroof
sold: '99 M3 Coupe
Cosmos Black
Airbox baffle removed, ZKW ellipsoid headlights, UUC short shift kit, BMW x-brace, debadged

'96 Jeep Grand Cherokee Laredo V8
(Support Vehicle)
  #4  
Old 05-27-2003, 07:55 AM
JST's Avatar
JST JST is offline
A sudden sense of liberty
Location: U of ///M
 
Join Date: Dec 2001
Posts: 3,936
Mein Auto: 535xiT, Golf R, 987S
Quote:
Originally posted by Jetfire
Preliminary replies to my posts on other mailing lists suggest that my other bearings were pretty much toast as well. The bearings should really have NO wear on them at all. They're supposed to be separated from the crank by a film of oil, so ideally there should be no contact whatsoever. And the journal on #4 is definitely in bad shape.
Sorry to hear that. What's the likely cause? And does that mean you'll need a new block?
  #5  
Old 05-27-2003, 08:01 AM
Jetfire's Avatar
Jetfire Jetfire is offline
Car Junkie
Location: N. VA
 
Join Date: Jun 2002
Posts: 3,397
Mein Auto: '88 M3, Ex-'99 M3
Quote:
Originally posted by JST
Sorry to hear that. What's the likely cause? And does that mean you'll need a new block?
I don't know the cause yet. Some amount of bearing wear is not unusual with these engines, but I certainly wouldn't expect to have the bearings down to the copper at only 82000 miles. I'll look through the vehicle service history to see if there are any clues; the car was babied for at least the last seven years and probably for its entire life, so I don't think it's related to hard driving. It's possibly related to a lack of maintenance, perhaps due to mileage-based service instead of time-based service. But that's all conjecture at this point; I honestly have no idea what might have caused it.

At this point, the crank will have to be replaced in order to prevent the bearings from dying quickly again. That will require engine removal. The connecting rods will have to be inspected to determine whether any of them are out of round; I wouldn't be surprised to see that #4 was pounded out from all of that contact.

In the short term, however, I plan to button up the car again and drive it a bit longer. Maybe an S14 with spun bearings can be bought for cheap, along with an engine stand. Hmm...
__________________

'88 M3
Conforti chip, Evo airbox/K&N filter, UUC short shift kit, oil pan baffle, Hella H4 lights, OEM glass sunroof
sold: '99 M3 Coupe
Cosmos Black
Airbox baffle removed, ZKW ellipsoid headlights, UUC short shift kit, BMW x-brace, debadged

'96 Jeep Grand Cherokee Laredo V8
(Support Vehicle)
  #6  
Old 05-27-2003, 08:09 AM
·clyde·'s Avatar
·clyde· ·clyde· is offline
OMGWTFBBQ
 
Join Date: Dec 2001
Posts: 11,265
Mein Auto:
Uh oh.

Maybe we should have just left that bolt on and not learned of this until total failure?

I was really hoping that nothing major would turn up
__________________
OH NOES!!!!!1 MY CAR HAS T3H UND3R5T33R5555!!!!!!1oneone!!!!11

Team WTF?!
What are you gonna do?
  #7  
Old 05-27-2003, 08:16 AM
Jetfire's Avatar
Jetfire Jetfire is offline
Car Junkie
Location: N. VA
 
Join Date: Jun 2002
Posts: 3,397
Mein Auto: '88 M3, Ex-'99 M3
Quote:
Originally posted by Clyde@work
Uh oh.

Maybe we should have just left that bolt on and not learned of this until total failure?

I was really hoping that nothing major would turn up
That certainly would have saved me another eight hours of my time.

Not sure what I'm going to do now. I kind of like the "drive it now, find an S14 on the side" approach, but I wonder just how long I will have before the bearings go bye bye again. I think, if this had been caught earlier, it would have been easily repaired just with the bearings. But we're talking a couple of thousand miles, not 100.
__________________

'88 M3
Conforti chip, Evo airbox/K&N filter, UUC short shift kit, oil pan baffle, Hella H4 lights, OEM glass sunroof
sold: '99 M3 Coupe
Cosmos Black
Airbox baffle removed, ZKW ellipsoid headlights, UUC short shift kit, BMW x-brace, debadged

'96 Jeep Grand Cherokee Laredo V8
(Support Vehicle)
  #8  
Old 05-27-2003, 08:25 AM
Kaz's Avatar
Kaz Kaz is offline
King of Rear Clunks
Location: OC, CA
 
Join Date: Dec 2001
Posts: 12,915
Mein Auto: 01 325iT, 88 M6
I'm far from an expert in the S14, but I know the one thing that may be related to this could be oil starvation down in the crank area. You probably already know this but a baffle is a very popular addon, as the S14 is really prone to oil climbing the block in long turns. This problem is worse, naturally, if the oil happens to be low. 82k mi does sound a bit low for bearing failure, though. My friend's 2nd car had a preventative bearing replacement recently and it has 150k+ mi on it. I think it might be a good idea, if you end up deciding not to replace the crank, to have it checked VERY carefully for trueness at every journal. The wear being different across the surface of #4 might mean something...
  #9  
Old 05-27-2003, 08:33 AM
Jetfire's Avatar
Jetfire Jetfire is offline
Car Junkie
Location: N. VA
 
Join Date: Jun 2002
Posts: 3,397
Mein Auto: '88 M3, Ex-'99 M3
Quote:
Originally posted by Kaz
I'm far from an expert in the S14, but I know the one thing that may be related to this could be oil starvation down in the crank area. You probably already know this but a baffle is a very popular addon, as the S14 is really prone to oil climbing the block in long turns. This problem is worse, naturally, if the oil happens to be low. 82k mi does sound a bit low for bearing failure, though. My friend's 2nd car had a preventative bearing replacement recently and it has 150k+ mi on it. I think it might be a good idea, if you end up deciding not to replace the crank, to have it checked VERY carefully for trueness at every journal. The wear being different across the surface of #4 might mean something...
The car has had a baffle for some time now, and the oil starvation issue really becomes a problem at sustained hard right turns. The way the car was driven in the past leads me to believe that the bearings didn't die from that particular form of starvation.

I did notice, however, that the electrode on spark plug #4 is already starting to turn white. This is a sign of very high combustion temps, I believe, which is a possible sign of running lean and detonation. It's possible that there's an intake gasket leak somewhere, which would cause detonation in that cylinder, which would then really stress the bearings and crank. The PO did mention a "pinging" sound at lower revs, so perhaps this is the real problem.
__________________

'88 M3
Conforti chip, Evo airbox/K&N filter, UUC short shift kit, oil pan baffle, Hella H4 lights, OEM glass sunroof
sold: '99 M3 Coupe
Cosmos Black
Airbox baffle removed, ZKW ellipsoid headlights, UUC short shift kit, BMW x-brace, debadged

'96 Jeep Grand Cherokee Laredo V8
(Support Vehicle)
  #10  
Old 05-27-2003, 08:38 AM
Kaz's Avatar
Kaz Kaz is offline
King of Rear Clunks
Location: OC, CA
 
Join Date: Dec 2001
Posts: 12,915
Mein Auto: 01 325iT, 88 M6
Quote:
Originally posted by Jetfire

I did notice, however, that the electrode on spark plug #4 is already starting to turn white. This is a sign of very high combustion temps, I believe, which is a possible sign of running lean and detonation. It's possible that there's an intake gasket leak somewhere, which would cause detonation in that cylinder, which would then really stress the bearings and crank. The PO did mention a "pinging" sound at lower revs, so perhaps this is the real problem.
Gee, why didn't you mention this before? You're right, this could definitely be a sign of something else on the top end. But top end problems are... well, top end problems. Do you really want to start into that and discover something else? I'd say it might be safer/easier/cheaper to swap the motor, but in the case o a S14 it probably won't be cheaper unless something pretty bad is going on. Good luck.
  #11  
Old 05-27-2003, 08:46 AM
Pinecone's Avatar
Pinecone Pinecone is offline
M Mad
Location: Maryland
 
Join Date: Apr 2002
Posts: 10,482
Mein Auto: M Roadster/M3
I have had a bearing go before. If the crank has damage you can feel, you can be pretty sure it will toast the bearing in about 30 seconds after you start it up.

You can try polishing the journal. Use a very fine wet/dry paper, used wet (oil) and something like a leather strap (old belt) to provide even pressure.

But it might still not work.

It is up to you whether to take the chance or just pulling the engine/crank and having it done right.

I don't know if the S14 crank can be turned any. If so, have it turned to the next size down and put in oversized bearing. If not, now might be a good time to think about the 2.5 crank.
__________________
Terry Carraway

'95 Alpine M3 LTW
'00 Dakar M Roadster
'02 Topaz M3
Red/White SRF #4 (Chassis 561)
  #12  
Old 05-27-2003, 09:56 AM
bren's Avatar
bren bren is offline
///Mpty pockets
Location: MD
 
Join Date: Jul 2002
Posts: 1,963
Mein Auto: wankermatic
Quote:
Originally posted by Jetfire
I kind of like the "drive it now, find an S14 on the side" approach...
There are a couple on s14.net for sale
 

Bookmarks


Forum Navigation
Go Back   Bimmerfest - BMW Forums > BMW Model Discussions > M Series
Today's Posts Search
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 On



Forum Jump


All times are GMT -7. The time now is 06:34 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
© 2001-2011 performanceIX, Inc. All Rights Reserved .: guidelines .:. privacy .:. terms