Brass Material Found in Engine Oil
#1
Brass Material Found in Engine Oil
Hey guys, I did some laps on the road course last week so I decided to change my oil a bit early (2,000 miles). However, much to my surprise I found little pieces of what appears to be brass bearing material in the catch pan (see picture).
Here's the kicker: my motor has 15 months/20,000 miles on it (reman). Oil has been regularly changed with what Mazda recommends (Mazda 5w-20). It was broken in properly, and although I do drive it hard, I also take the proper precautions; i.e. slight warm up, cool down to even out internal temps and hot spots, rev downs when necessary, etc. It's NEVER been low or high on oil, or overheated in any way. I even pop the hood and let it completely cool every few runs. Plus rotaries like being driven hard, right?
The car still runs perfectly, and I wouldn't have known otherwise. Part of me is hoping it's residual break-in material that's been hanging around in the pan, and the hard braking/turning oriented it correctly for draining. I also flushed with a fresh quart this time which I haven't done before... Just being hopeful I suppose.
So long story... well long, should I be concerned or are particles of this size somewhat normal for a newish motor?
Here's the kicker: my motor has 15 months/20,000 miles on it (reman). Oil has been regularly changed with what Mazda recommends (Mazda 5w-20). It was broken in properly, and although I do drive it hard, I also take the proper precautions; i.e. slight warm up, cool down to even out internal temps and hot spots, rev downs when necessary, etc. It's NEVER been low or high on oil, or overheated in any way. I even pop the hood and let it completely cool every few runs. Plus rotaries like being driven hard, right?
The car still runs perfectly, and I wouldn't have known otherwise. Part of me is hoping it's residual break-in material that's been hanging around in the pan, and the hard braking/turning oriented it correctly for draining. I also flushed with a fresh quart this time which I haven't done before... Just being hopeful I suppose.
So long story... well long, should I be concerned or are particles of this size somewhat normal for a newish motor?
#2
Registered
5w20 is not ok, the viscosity to low; it was prescribed by Mazda only for fuel efficiency targets etc. in the USA.
In the rest of the world at least a (5)w30 grade is advised by Mazda.
In the UK and on the European continent most Wankelexperts use/advise a (-)w40 or (-)w50 grade.
Many people use a 20w50 grade, which is better for the bearings of the excentric shaft
In the rest of the world at least a (5)w30 grade is advised by Mazda.
In the UK and on the European continent most Wankelexperts use/advise a (-)w40 or (-)w50 grade.
Many people use a 20w50 grade, which is better for the bearings of the excentric shaft
#3
BECAUSE RACECAR
iTrader: (10)
5w-20 is too thin, especially for road course use where oil temps can easily reach 240+ degrees if it is hot outside, meaning that the oil thins out even more.
No idea if that will soon lead to catastrophic failure but that much bearing material in the oil from a motor that should already be fully broken in is not good...
No idea if that will soon lead to catastrophic failure but that much bearing material in the oil from a motor that should already be fully broken in is not good...
Last edited by Arca_ex; 06-23-2014 at 02:58 AM.
#5
Registered
iTrader: (1)
Arca has it right. If you're planning on doing any sort of tracking, you need to up the weight in order to compensate for the higher temps. Or if you live in warmer climate you need to increase the weight.
As for the metal, a side effect of having too thin of oil, dunno what it came from.
As for the metal, a side effect of having too thin of oil, dunno what it came from.
#6
SARX Legend
iTrader: (46)
I would send a sample in to be tested to Blackstone. Has this car had an engine failure previously? It is common for people to not clean out the oil coolers after a failure so if it had bearing failure before it could be debris in the coolers from that. Also 5W20 (depending on brand) is way too weak for track abuse. I recommend a good 40. I use mobil1 0W-40 but there are a few good options. If you are cost conscious try Rotella T6 5W-40 or 10W-40.
#9
Thanks for all the replies. Honestly the thin oil theory makes a lot of sense . The engine was replaced not rebuilt, and I'm not sure if the lines were flushed. It could just as well have been current break-in material circling around in the ~52% of oil that doesn't get drained each time.
But as suggested, the most likely explanation is probably thin oil and high temps. Sad face. Well I suppose I'll change the oil to something heavier after a couple hundred miles and see how it looks then. Hopefully the car lasts that long.
Any suggestions as to what a good viscosity would be? I've done some searching, and even on this thread there seems to be a broad range options. I do mostly daily driving with track days every month or two, and in a fairly warm climate during the summer. If the motor lasts until winter I'll cross that bridge when I get there 😂.
But as suggested, the most likely explanation is probably thin oil and high temps. Sad face. Well I suppose I'll change the oil to something heavier after a couple hundred miles and see how it looks then. Hopefully the car lasts that long.
Any suggestions as to what a good viscosity would be? I've done some searching, and even on this thread there seems to be a broad range options. I do mostly daily driving with track days every month or two, and in a fairly warm climate during the summer. If the motor lasts until winter I'll cross that bridge when I get there 😂.
#20
Apparently not!
Last edited by 6speedrx; 06-24-2014 at 10:15 PM.
#21
I don't "smell good".
Join Date: Dec 2001
Location: Crowfield Plantation, SC
Posts: 910
Likes: 0
Received 0 Likes
on
0 Posts
5w-20 too thin? You better not tell that to my engine. 74,000 miles of whatever crap 5w-20 that's on sale on it mixed with about half a quart of MMO. Changed normally every 3k miles. Sometimes 4-5k.
I guess my engine should have died thousands of miles ago instead of running like new. Interesting.
I guess my engine should have died thousands of miles ago instead of running like new. Interesting.
#22
BECAUSE RACECAR
iTrader: (10)
5w-20 too thin? You better not tell that to my engine. 74,000 miles of whatever crap 5w-20 that's on sale on it mixed with about half a quart of MMO. Changed normally every 3k miles. Sometimes 4-5k.
I guess my engine should have died thousands of miles ago instead of running like new. Interesting.
I guess my engine should have died thousands of miles ago instead of running like new. Interesting.
#24
Too old for PC
And MMO is as much solvent as lubricant. Probably also affects viscosity rating to the thin side even more. My bet is his journal bearings aren't anything to brag about, even at relatively low miles. If quality oil is used, additives aren't needed.