Member
Gold Dust in Oil
Expecting Bad News Here...
I was driving home last week and a noticeable engine knock started about two blocks from my house, I pretty much coasted home and haven’t driven it since. I popped the oil filter cap and saw some gold glitter when I shined a flashlight in… I took some oil and had it analyzed. With a high copper count, I am assuming that a connecting rod bearing has spun.
Prior to this I have had an oil leak (OFHG) and upon dumping my oil, there was only 4.5 Qts (6.5 required). I’m sure that low oil could have caused this, unfortunately there was no “Low oil” warning.
My question is if I have any options besides engine replacement? There was most likely some wear happening before the audible knock, but it really wasn’t driven with the knock. Is it possible that bearing replacement, crank polishing and fixing the oil leak will give me some time?
Here is a link to my Oil Analysis Results:
https://drive.google.com/file/d/11K7...ew?usp=sharing
Member
Golden Glitter Oil
I am expecting bad news...
I was driving home last week and a noticeable engine knock started about two blocks from my house, I pretty much coasted home and haven’t driven it since. I popped the oil filter cap and saw some gold glitter when I shined a flashlight in… I took some oil and had it analyzed. With a high copper count, I am assuming that a connecting rod bearing has spun.
Prior to this I have had an oil leak (OFHG) and upon dumping my oil, there was only 4.5 Qts (6.5 required). I’m sure that low oil could have caused this, unfortunately there was no “Low oil” warning.
My question is if I have any options besides engine replacement? There was most likely some wear happening before the audible knock, but it really wasn’t driven with the knock. Is it possible that bearing replacement, crank polishing and fixing the oil leak will give me some time?
Member
Actually I don’t think the engine ran out if oil if there is still 4.5 quarts of oil in the engine. But, as there’s no dipstick, you don’t know how much oil is in the engine. Thanks BMW. Remember, the oil pump sits near the bottom of the oil pan. I’d send a sample if of the oil to Blackstone Labs for analysis. Go to its website to get a free oil sample bottle kit.
Oh, please don’t double post. It confuses people. Just sayin’.
Member
What is in the oil filter pleats? No need for oil analysis when bearing flakes are present and it's knocking.
As to repairs; If simply a spun bearing then perhaps a crank(regrind?)and bearings will fix you up.
The root cause needs to be determined first to know if the motor just needs to be trashed or if worth fixing. Overhauls are very expensive, used replacements not so much.
If replacing try hard to find a running wreck where the engine can be demonstrated. You can wipe your ass with junkyard warranties as you'll be on the hook for labor if you get a turd and the replacement(if you get one)is another crap shoot.
Last edited by ross1; 01-26-2020 at 10:08 AM.
If you can leave two black stripes from the exit of one corner to the braking zone of the next, you have enough horsepower. - Mark Donohue
Member
My 0.02$ based on a personal experience very similar to yours (except the knock was there before it happened because the previous owner had overheated the engine) :
4.5qts+coasting can result in oil starvation. In my case it resulted in a lack of lubrication to the chain tensioner, which apparently caused a spark plug thread to overheat and break.
The engine survived for a couple years after repairing the plug thread and it eventually blew up (didn't appreciate a spirited driving session with an injectors cleaner in the tank: the sh*t we learn the hard way... ).
Only when I had to replace the engine (not worth fixing given the cost and an end result not guaranteed at all) did I realize that the previous one, although brave, wasn't in the best shape.
So agreed with ross1 about replacing rather than repairing. A little tip: if you can find a Japanese import chances are it's going to be good because small country = higher chances of low mileage, and Japanese fuel is rated either 98 or 102 octane so it'd have had little to no knock during its life there.
Member
Hey Everyone,
Thank you for your help. This is my first BMW and my first post on this forum.
As for the oil filter, there was a very fine gold metallic dust and a couple small and very fine silver metal shavings. I have attached a picture of the oil and a video with the knock sound.
https://drive.google.com/open?id=1ct...SWaIQKYYjPH7dz
https://drive.google.com/open?id=1Ss...XhHWbF-7kkyXyz
I've been looking around for a used motor and can't find an N55 for less than 4K Shipped. Adding in labor (Quoted $1,200 for the swap), and new gaskets (Valve Cover, Oil Pan, OFHG). It looks like it will be around $6K to replace.
Member
If you have time it may be worth waiting for a better price, and buy locally if at all possible. Looks like you are approaching 50% value, an insurance co would total it.Originally Posted by beatty
If so inclined you could buy an entire wreck(ostensibly the engine was running)and sell off the remains to subsidize the project.
What's this thing worth to you? Might just be time to cut bait.
Good luck.
Last edited by ross1; 01-30-2020 at 11:57 AM.
If you can leave two black stripes from the exit of one corner to the braking zone of the next, you have enough horsepower. - Mark Donohue
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