Parts Catalog Accessories Catalog Tech Info Tech Forums
 
  Search our site:    
 Cart  | Project List | Order Status | Help    
  Join us November 1st for Casino Night at the Pelican Parts Open House!
Benefiting LuMind - Research and Treatment for individuals with Down Syndrome
Go Back   Pelican Parts Technical BBS > 1- Porsche Technical Forums > Porsche 924/944/968 Technical Forum

Reply
 
LinkBack Thread Tools Rate Thread
Author
Thread Post New Thread    Reply
Registered User
 
Join Date: Aug 2004
Location: Grand Rapids, MI
Posts: 2,678
Garage
Angry Just spun a rod bearing at the track tonight!

I was doing a test & tune at Gingerman Raceway tonight and was feeling good. My previous best times were 1:47 there. To put it in perspective my friend's 996 with some mods runs 1:42's. I managed to click off a 1:46 and two 1:45 laps tonight, which was faster than the slower cars in the Porsche club race there last Sunday.

Then it happened...an odd noise coming from the engine, temp going up. I got it into the pits and shut it down as quick as I could but it definitely spun a rod bearing. I just hope the damage isn't too bad.

Either way, my track season is probably over.
__________________
Michael
Sans Porsche...for now
2009 Mazdaspeed 3 Grand Touring daily driver / DS autocross toy
2010 Subaru Forester X Limited - wife's daily driver
Old 07-12-2007, 07:38 PM
  Recommend this thread for the PelicanWiki    Reply With Quote #1 (permalink)
Registered User
 
fast924S's Avatar
 
Join Date: Jun 2003
Location: New Haven, CT
Posts: 3,343
Garage
Send a message via AIM to fast924S
ohhh man, that sucks, Sorry to hear about it, Hope its not to bad. Time to install a oil pan baffel and ring around the pickup along with some crank work
__________________
1986 951, Stock for now.
]87 924S Gaurds red- SOLD after 11 years of ownership
Old 07-12-2007, 07:44 PM
  Recommend this thread for the PelicanWiki    Reply With Quote #2 (permalink)
Registered User
 
Join Date: Aug 2004
Location: Grand Rapids, MI
Posts: 2,678
Garage
Thanks.

That's what bothers me so much is that this motor has the later baffled oil pan. I'll pick it up from the track tomorrow with a trailer and see what I find. I'll probably drain the oil first on Saturday to see if there's much metal/bearing in it. If the oil's still pretty clean I'm probably not in too bad of shape. Now I need to figure out whether I'm better off fixing this motor or just buying another one to put in.
__________________
Michael
Sans Porsche...for now
2009 Mazdaspeed 3 Grand Touring daily driver / DS autocross toy
2010 Subaru Forester X Limited - wife's daily driver
Old 07-12-2007, 07:53 PM
  Recommend this thread for the PelicanWiki    Reply With Quote #3 (permalink)
Registered User
 
924RACR's Avatar
 
Join Date: Sep 2005
Location: Royal Oak, MI
Posts: 1,195
Bummer - those are some pretty decent times too; I think the ITA record is about 1:45 or 1:44.

When were the bearings last done?

I'd recommend you consider installing a crank scraper in there too, to help control oil flow and free up a little power while you're at it; in particular, they're pretty easy to install while doing rod bearings, if you're lucky enough to be able to replace them without further machining. Crank-scrapers.com has them, is where I got mine (no affiliation other than happy customer).
__________________
Vaughan Scott
http://www.vaughanscott.com
http://www.924.org
Old 07-13-2007, 05:59 AM
  Recommend this thread for the PelicanWiki    Reply With Quote #4 (permalink)
Registered User
 
Join Date: Aug 2004
Location: Grand Rapids, MI
Posts: 2,678
Garage
Thanks for the info Vaughan, I'll do some checking on the crank scrapers.

I am really happy to have been down to 1:45 laps with that car at Gingerman, but I've probably got 4-5 hours on that track so far this year so I'm really getting the line down too.

I'm picking the car up with a trailer this afternoon, I'll drain the oil tomorrow to see if there's much metal/bearing material in it.

The motor was rebuilt by a shop in IL 3-4 years ago due to a spun rod bearing at that time. Supposedly (according to the receipts) a baffled oil pan was installed along with all new bearings, etc. at that time.

I'm not running R-compounds on the car so I really didn't think I was cornering hard enough to do damage, but I guess i was wrong. The only other thing I can think of is I may have over-revved the motor on a downshift from 4-3 or something, but I wouldn't expect that to result in a spun bearing as much as bent valves.
__________________
Michael
Sans Porsche...for now
2009 Mazdaspeed 3 Grand Touring daily driver / DS autocross toy
2010 Subaru Forester X Limited - wife's daily driver
Old 07-13-2007, 07:08 AM
  Recommend this thread for the PelicanWiki    Reply With Quote #5 (permalink)
Will work for parts
 
944 boy's Avatar
 
Join Date: Oct 2002
Location: Silicon Valley
Posts: 887
Send a message via AIM to 944 boy
What kind of oil pressures have you been seeing? Also where do you run the oil on the dipstick? Even slightly low oil when racing can cause starving. Also you may want to get an 951 oil cooler as well. I put a crank scraper in the last motor I rebuilt but im not putting one in this motor, just fordged rods and new parts. Good Luck!
__________________
'88 944 240,100 miles -race car
'05 Boxster 110,000 - Daily Driver
'74 911 Targa - long term project
Old 07-13-2007, 09:44 AM
  Recommend this thread for the PelicanWiki    Reply With Quote #6 (permalink)
 
Now Available for Ordering:   101 Projects For Your BMW 3 Series 1982-2000  [more info]
Registered User
 
Join Date: Aug 2004
Location: Grand Rapids, MI
Posts: 2,678
Garage
I don't know if the car was rebuilt with a higher pressure oil pump or not, but it's usually between 4-5 bar depending on the temps, engine revs and cornering direction. When the engine started making a bit of noise the pressure was between 2-3 bar and when I pulled into the pit space and the engine started to idle the pressure dropped further and the low pressure light came on. I shut it off instantly when the light came on. I usually run the oil midway between the marks on the dipstick.

Thanks for the input on the oil cooler. I'm going to decide what to do in the next few days. I'm actually kicking arround whether or not I want to get a 951 gearbox, brakes, etc, and do an LS-1 conversion. I don't know if I have the budget for it though. I don't plan on racing this car in any series, I would build or buy one and race in 944 cup if I were going racing, which I hope to do in a few more years.
__________________
Michael
Sans Porsche...for now
2009 Mazdaspeed 3 Grand Touring daily driver / DS autocross toy
2010 Subaru Forester X Limited - wife's daily driver
Old 07-13-2007, 01:01 PM
  Recommend this thread for the PelicanWiki    Reply With Quote #7 (permalink)
Will work for parts
 
944 boy's Avatar
 
Join Date: Oct 2002
Location: Silicon Valley
Posts: 887
Send a message via AIM to 944 boy
Generally most people run the oil a hair above the top mark, not too much or you will get foaming, but .5 qt or less above. Due to the symptoms I agree that you spun something. Its a bummer, but maybe you might want to look into boring it out to a 2.8L :-)
__________________
'88 944 240,100 miles -race car
'05 Boxster 110,000 - Daily Driver
'74 911 Targa - long term project
Old 07-13-2007, 02:26 PM
  Recommend this thread for the PelicanWiki    Reply With Quote #8 (permalink)
Registered User
 
Join Date: Aug 2004
Location: Grand Rapids, MI
Posts: 2,678
Garage
I'm hoping the crank is okay and I can just have it polished, replace the rod and offending bearing, but that's a long shot. I'll have to see how much material is or isn't in the oil when I drain it later...
__________________
Michael
Sans Porsche...for now
2009 Mazdaspeed 3 Grand Touring daily driver / DS autocross toy
2010 Subaru Forester X Limited - wife's daily driver
Old 07-13-2007, 03:07 PM
  Recommend this thread for the PelicanWiki    Reply With Quote #9 (permalink)
Registered User
 
Join Date: May 2006
Location: Sterling, IL (Chicago area)
Posts: 478
Quote:
Originally posted by vanwyk4257
Thanks for the info Vaughan, I'll do some checking on the crank scrapers.

I am really happy to have been down to 1:45 laps with that car at Gingerman, but I've probably got 4-5 hours on that track so far this year so I'm really getting the line down too.

I'm picking the car up with a trailer this afternoon, I'll drain the oil tomorrow to see if there's much metal/bearing material in it.

The motor was rebuilt by a shop in IL 3-4 years ago due to a spun rod bearing at that time. Supposedly (according to the receipts) a baffled oil pan was installed along with all new bearings, etc. at that time.

I'm not running R-compounds on the car so I really didn't think I was cornering hard enough to do damage, but I guess i was wrong. The only other thing I can think of is I may have over-revved the motor on a downshift from 4-3 or something, but I wouldn't expect that to result in a spun bearing as much as bent valves.
In a racing environment, I'd cross drill the crank, replace the rod bearings every 2-3 years depending on use, and run the oil at or just above the full mark religiously.

Get it rebuilt well once, put a cage in it, and come racing - more fun than you'll ever have if you spent the $$ on a V-8 conversion.

In any case, sorry to hear it, and good luck!
Old 07-13-2007, 10:40 PM
  Recommend this thread for the PelicanWiki    Reply With Quote #10 (permalink)
Registered User
 
Join Date: Feb 2000
Location: Kingsport, TN
Posts: 2,905
What was your oil level after the incident? I was at the track this past weekend (Road Atlanta). I was doing some slow laps breaking in a new turbocharger and did not have the engine overfilled by the usual 1/2 quart. At one point in a left turn after heavy braking, I noticed the oil pressure drop to 3 bars from the usual 5 bars. My pan has extra baffles, a little swinging door, and an oil pickup that is closer to the bottom of the sump. I immediately returned to the pits and gave it the slight overfill. Pressure drop never occurred again.
__________________
Lawrence
1986 951
2002 SLK32 AMG
1987 328GTS
2011 528i

Last edited by Lawrence Coppari; 07-14-2007 at 03:39 AM..
Old 07-14-2007, 03:33 AM
  Recommend this thread for the PelicanWiki    Reply With Quote #11 (permalink)
Registered User
 
Join Date: Aug 2004
Location: Grand Rapids, MI
Posts: 2,678
Garage
Sterling Doc, I would like to go racing, but I don't have the budget for it at this point. I have a few friends that race, and I know that even on a shoestring I'm looking at $10,000 for a year's racing. At some point I plan on possibly joining the 944cup or Supercup series depending on what car I have at that point.

I appreciate the advice on crossdrilling the crank. I think I'm going to purchase another engine and put it in the car so I can at least try to get back on the track yet this season for a while, then I can take my time with rebuilding and upgrading the other motor that is in the car now.

Lawrence. After the incident the oil was just above the lower mark on the dipstick, which obviously is a bit low. I've put the "keep the oil just above full" advice a few of you have given in the "it would have been nice to know that before" catagory.

I appreciate all the good information you guys have given me and I will definitely be putting it to use when I rebuild the engine.
__________________
Michael
Sans Porsche...for now
2009 Mazdaspeed 3 Grand Touring daily driver / DS autocross toy
2010 Subaru Forester X Limited - wife's daily driver
Old 07-14-2007, 06:07 AM
  Recommend this thread for the PelicanWiki    Reply With Quote #12 (permalink)
Registered User
 
924RACR's Avatar
 
Join Date: Sep 2005
Location: Royal Oak, MI
Posts: 1,195
Accusump. 'Nuff said.

As for budgeting... you can have a helluva lot of fun for $10k a year!!! $5k is probably more like it - 944's are relatively easy on tires, etc. I'm at $3k/year (6 weekends), including beer and entry fees (the former not inconsiderable, if you know my team!) but then I do race a dinky little 2.0L and local entry fees are cheaper than anywhere else (usually $150/weekend).
__________________
Vaughan Scott
http://www.vaughanscott.com
http://www.924.org
Old 07-14-2007, 09:46 AM
  Recommend this thread for the PelicanWiki    Reply With Quote #13 (permalink)
Registered User
 
Join Date: Aug 2004
Location: Grand Rapids, MI
Posts: 2,678
Garage
That's good to know. Here are my two video clips from Thursday night.

http://www.youtube.com/watch?v=mh9YeNRb_M4

http://www.youtube.com/watch?v=luA1xBGkl9U
__________________
Michael
Sans Porsche...for now
2009 Mazdaspeed 3 Grand Touring daily driver / DS autocross toy
2010 Subaru Forester X Limited - wife's daily driver
Old 07-14-2007, 10:11 AM
  Recommend this thread for the PelicanWiki    Reply With Quote #14 (permalink)
Registered User
 
Join Date: Aug 2004
Location: Grand Rapids, MI
Posts: 2,678
Garage
Well, I've located a replacement engine from an '83 944 that I will be picking up this coming Saturday. I plan on installing the baffled oil pan, a crank scraper, and doing timing belts and the water pump before installing it. It only has 78,000 miles on it, but would you guys recommend replacing the rod bearings before I put it in the car? Any other things I should do to the motor before I install it?

I will be putting the old engine on a stand and opening it up later on. I will probably have the crank crossdrilled and if necessary reground. That way once I get it back together I will have a good solid backup motor in case anything happens to the one I'm putting in soon.

Thanks in advance for the advice guys!!
__________________
Michael
Sans Porsche...for now
2009 Mazdaspeed 3 Grand Touring daily driver / DS autocross toy
2010 Subaru Forester X Limited - wife's daily driver
Old 07-15-2007, 04:20 PM
  Recommend this thread for the PelicanWiki    Reply With Quote #15 (permalink)
Registered User
 
924RACR's Avatar
 
Join Date: Sep 2005
Location: Royal Oak, MI
Posts: 1,195
Are you FRIGGIN' kidding me??? I'd put new rod bearings in ANY engine, unless it belonged to a little old lady who only drove it to church on Sundays, and only had 20kmi!!! It's a no-brainer.

The bigger question is, why not put in new mains and rings while you're at it? And lap the valves in too. No good reason not to - it's called preventative maintenance.

The only time I ever put an untouched engine in my car, it chewed itself up in the first session (2 bar oil pressure no matter the revs). Just not worth the time, there's never any easier time to do it that while it's out of the car.

Take it to the coin-op carwash, blast the whole outside clean. Then home, on a stand, all new parts from a re-ring kit.
__________________
Vaughan Scott
http://www.vaughanscott.com
http://www.924.org
Old 07-16-2007, 04:28 AM
  Recommend this thread for the PelicanWiki    Reply With Quote #16 (permalink)
Registered User
 
Join Date: Aug 2004
Location: Grand Rapids, MI
Posts: 2,678
Garage
Vaughan, let me ask the natural question then. Is it even worth picking up the spare motor or should I just rebuild the one that's in the car now?
It sounds like I'm looking at a similar amount of work no matter what...
__________________
Michael
Sans Porsche...for now
2009 Mazdaspeed 3 Grand Touring daily driver / DS autocross toy
2010 Subaru Forester X Limited - wife's daily driver
Old 07-16-2007, 05:03 AM
  Recommend this thread for the PelicanWiki    Reply With Quote #17 (permalink)
Registered User
 
924RACR's Avatar
 
Join Date: Sep 2005
Location: Royal Oak, MI
Posts: 1,195
Yes it is, because no, it's less work - it shouldn't require machining, only replacement of wear items. You should be able to just order up new stock size parts, and swap them in. Everything else will just be cleaning!
__________________
Vaughan Scott
http://www.vaughanscott.com
http://www.924.org
Old 07-16-2007, 08:49 AM
  Recommend this thread for the PelicanWiki    Reply With Quote #18 (permalink)
Old 07-16-2007, 08:49 AM
Reply

Thread Tools
Rate This Thread
Rate This Thread:

 



All times are GMT -8. The time now is 08:04 PM.


 
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2011 Pelican Parts - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page
 

DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.