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Discussion Starter · #1 ·
I think I blew a rod bearing cap through the oil pan or block. :sad3:


I was at Monticello Motor Club, a great technical track, and on my 4th time out for the day, coming around a turn, full acceleration in 3rd - maybe 4000 - 6000 rpms, and blue smoke out the front right wheel well, then loss of power, loss of power steering, etc.
at first I thought I blew a tire, then I thought I busted the fan belts. but after I got out of the car, I saw a trail of oil, and oil coming out from under the engine. tires were fine. fan belts fine.


the flag man said he saw flames under the car when it happened.
the Porsche driver in back of me said he saw a ball of flame coming out from under the car.
I assume it was engine oil hitting hot exhaust pipe.
I found a 2" x 2" piece of oil pan or engine block when we rolled the car off the flatbed.
interestingly enough, the dip stick still shows being only 3/4 of a quart low on oil.
i'm not sure what turns when i engage the starter motor, but it is not making compression to start the motor.


what probably happened:
a rod bearing was bad, and it blew under the constant pressure of running up gears 2, 3 and 4 to close to redline.


in the week or 2 before track day, I heard a tapping at startup, occasionally when cold.
I kept thinking it sounds like a rod bearing, but then would think maybe it's gear lash (that usually happens, buy only when warm).
it made no sense to me that a rod bearing would be bad.
I also heard continual tapping occasionally, in first gear, 2000 - 3000 rpms, under very light throttle.
prior to that last circuit, I think I heard it as I was moving forward in the line of cars getting ready to go out on the track.
but I kept thinking .."it can't be"...


so the car is at Motor Works West in Wyckoff, NJ.
I will get an update from them when they put it up on a lift.


Lessons learned:
When the car tells you something, listen to it!
Stop and fix the problem, before it gets worse!
Try not to rationalize something as something other than what the facts are telling you.


i placed a "wanted to buy" for a used engine in the "wanted/for sale" threads, because it will probably be less expensive than repairing the 58,000 mile motor.
if anyone knows where i can put my hands on one, please let me know.
 

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Discussion Starter · #3 ·
maybe - i will PM him.
thanks.
 

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So sorry to hear...Stock redline or raised? Do you know the history of oil changes (when and with what oil)?

GL with the engine replacement.
 

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Discussion Starter · #6 ·
stock engine/redline. i change the engine oil every 5 - 10,000 miles, 5 - 30 synthetic, but i only owned it for 20,000 miles.
i did change the engine oil and filter, transmission oil and brake fluid, etc. in preparation for track day.
 

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Discussion Starter · #10 ·
58,000.
i don't know what could have caused the rod noise, though.
 

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Thanks for the reply...I'm assuming BMW 5-30 vs. the regular Castrol synthetic or other?
 

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Discussion Starter · #12 ·
i am not sure. it was done at the local indy shop, who advised me to have him put in 10 - 60. i told him 5 - 30, but i didn't specify BMW 5 - 30.
 

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Discussion Starter · #13 ·
my first 10,000 owned miles had BMW oil. the last 10,000 miles was NOT a BMW synthetic. it was castrol, or quaker state. could that have been the downfall?
i did track it at Watkins Glen last September with that new oil in it.
 

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This isn't an oil type issue, it is a defective rod bearing issue as you surmised. Happens occasionally, even though the engine was perfectly maintained and not abused. Member Tranck spun a rod bearing at similar mileage for no apparent reason. Looks like a case of really bad luck. If you have a good relationship with your dealer, you might be able to score some relief. Otherwise, time for a replacement used engine.

Sorry to hear about your misfortune...:crying:

Dave
 

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Discussion Starter · #15 ·
This isn't an oil type issue, it is a defective rod bearing issue as you surmised. Happens occasionally, even though the engine was perfectly maintained and not abused. Member Tranck spun a rod bearing at similar mileage for no apparent reason. Looks like a case of really bad luck. If you have a good relationship with your dealer, you might be able to score some relief. Otherwise, time for a replacement used engine.

Sorry to hear about your misfortune...:crying:

Dave
i appreciate your comments.
thanks.:dunno:
 

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I've said it before in other threads and I'm saying it again. Everytime I read one of these threads I feel like proactively replacing my bearings. That's REALLY low mileage for this type of failure. I general we say they're flukes, but a fluke is one thread per year...not one every couple months. Extrapolate the failure rate to all E39 M5s...not just m5board members.

JMHO of course.
 

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I've said it before in other threads and I'm saying it again. Everytime I read one of these threads I feel like proactively replacing my bearings. That's REALLY low mileage for this type of failure. I general we say they're flukes, but a fluke is one thread per year...not one every couple months. Extrapolate the failure rate to all E39 M5s...not just m5board members.

JMHO of course.
Much has been written on the subject, as I'm sure you and Paul know. Personally I wouldn't worry about it unless I were planning to track a higher mileage engine. As Paul indicated, there was advance warning with a suspect tapping sound. It probably wouldn't be a bad idea to occasionally listen to your engine. I listen to mine while it is parked in the garage so that the sounds bounce off a nearby wall and into the cabin. You can hear bottom end noise very easily this way (I had a previous car with a loose bottom end). At the first sign of suspicious sound, consider further diagnosis and possible bearing replacment. Do NOT take it to the track... ;)

Another member had his bearings done shortly after hearing rod tap. The crank/rod was not sufficiently pounded, and the all is well.

Dave
 

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Paul, sorry to hear about your loss. :crying:

How often do you change your oil (miles) and what brand and type do you use?

The only thing I can think of is poor maintance or a defective internal part such as a rod, etc.

Again so sorry to hear and hope things work out.
 

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5-10k mile intervals on regular old 5w30 synthetic is unacceptable. If this was done for the life of the car, you could have had gradual bearing wear, loss of pressure due and finally catastrophic failure during track use.

You should ALWAYS change oil prior to AND after a track event.

UOAs might have likely been an early warning that something was up. (For those thinking of prophylactic replacement, why no sample you oil and see if there are bearing metals in it? IF so THEN it is worth the expense to repalce....)

If one really wanted to get to the bottom of it, a careful disassembly and inspection of your bearings would be interesting. I wouldn't pay someone to do it, but I'd do it out of curiosity,

Good luck

A
 
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