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Blackstone Labs Results (Oil Analysis)
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The picture pretty much says it all. I'm concerned about the copper, lead, and gas dilution results. Can somebody tell me how normal these are? Should I be worried?
S4 N/A, rebuilt about 3500 miles (2 years) ago with used housings Also this part, "Caution! Is the oil level rising?" That would be a yes... https://www.rx7club.com/attachment.p...d=231565&stc=1 |
6x higher on the Cu, and almost 7x higher on the Pb?
I'd say you got premature bearing wear...if the "universal averages" are accurate. -Ted |
Originally Posted by RETed
6x higher on the Cu, and almost 7x higher on the Pb?
I'd say you got premature bearing wear...if the "universal averages" are accurate. -Ted Would the gas dilution cause that? |
Would the gas dilution cause that? |
Originally Posted by Aaron Cake
Yep. It drastically thins the oil. Did you ever run 10-30?
Since 10w30 was my previous oil change prior to the tested one (20w50), could some of (all?) of the copper/lead be from the residual oil left in the system? |
Very high copper and lead content but very low molybdenum (only 12% of "universal average" levels) which is a primary friction reducing agent. Coincidence?
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Originally Posted by rotarygod
Very high copper and lead content but very low molybdenum (only 12% of "universal average" levels) which is a primary friction reducing agent. Coincidence?
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Originally Posted by rotarygod
Very high copper and lead content but very low molybdenum (only 12% of "universal average" levels) which is a primary friction reducing agent. Coincidence?
Anyways, what would be causing this? Just the gas dilution? I'm also assuming that Castrol GTX doesn't contain Boron. :p: |
uttttttt oh .... we arn't supposed to use 10-30?? *feels stupid*
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Originally Posted by Aaron Cake
Yep. It drastically thins the oil. Did you ever run 10-30?
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Originally Posted by j9fd3s
that would be like, what additives are in the oil, and not the grade
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Originally Posted by rotarygod
The additive package is what makes a motor oil a motor oil. Without them, any base stock is worthless as a lubricant. The base stock is very important in other ways though. This oils shows abnormally low amounts of one of the main actual antifriction agents in the oil which doesn't look too good.
Thanks ahead of time. :) |
This is the first time I have ever seen this for a rotary...interesting to say the least.
Normally, you see this sort of thing for aircraft engines. On the upside for those engines there is a very established baseline since so many samples are sent in. Maybe you could find a few rotary aviation guys and ask if they sample their oil and get a look at their sheets to see what it looks like. It would be interesting if a few more people here did this. You should ask the company that did this if their base line is rotary specific. Besides, I always though we had more gas in our oil? James |
It looks like they're suggesting that you're leaking fuel into your oil, which is causing the oil to thin and bearing wear to increase. It does say on the sheet that the baselines are for a Mazda 1.3L Rotary, so that's taken into account. I can't think of how the gas and the oil would meet though, unless you're getting severe leakdown from leaking injectors, and keeping your oil in too long between oil changes. . .
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Here a couple of threads from the rx8club forum on blackstone analysis tests. Compare them to yours.
http://www.rx8club.com/showthread.ph...t=oil+analysis http://www.rx8club.com/showthread.ph...t=oil+analysis |
Originally Posted by Dr4900n
Could you explain this further or point us to a thread?
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One of the ones rotarygod linked mentioned gas in the oil. They said it could be due to lots of idling and city driving. Most of my driving is city... hmmm...
Originally Posted by Richter12x2
It looks like they're suggesting that you're leaking fuel into your oil, which is causing the oil to thin and bearing wear to increase. It does say on the sheet that the baselines are for a Mazda 1.3L Rotary, so that's taken into account. I can't think of how the gas and the oil would meet though, unless you're getting severe leakdown from leaking injectors, and keeping your oil in too long between oil changes. . .
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just drive it till it blows
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Originally Posted by My5ABaby
One of the ones rotarygod linked mentioned gas in the oil. They said it could be due to lots of idling and city driving. Most of my driving is city... hmmm...
This oil had 1500 miles and I had my injectors professionally cleaned about 2 years ago (less than 2000 miles). Ooh, I've got it - how about a faulty fuel pressure regulator? |
Originally Posted by Richter12x2
Maybe that's it, but that seems like a substantial amount of gas in your oil.
Ooh, I've got it - how about a faulty fuel pressure regulator? |
I think you need to stop putting penny's in when you change the oil. That'll lower your copper content :)
Seems like decent mileage though. I'd imagine the speculations about bearing wear would be accurate. I'm not aware of many other high-wear parts that contain copper in the engine actually :scratch: Very interesting test though, where did you have this done? (never heard of it, learn something new everyday) |
Originally Posted by My5ABaby
Never tested it... guess I could. I average about 17mpg with 5/6th ports open all the time (yeah yeah, I'll fix it this summer :) ). That's pretty good for a semi-hilly city.
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Just a thought, but could bad oil control rings let more gas into the oil than normal?
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Originally Posted by Sideways7
Just a thought, but could bad oil control rings let more gas into the oil than normal?
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Originally Posted by classicauto
I think you need to stop putting penny's in when you change the oil. That'll lower your copper content :)
Seems like decent mileage though. I'd imagine the speculations about bearing wear would be accurate. I'm not aware of many other high-wear parts that contain copper in the engine actually :scratch: Very interesting test though, where did you have this done? (never heard of it, learn something new everyday) They'll send you a free "kit" to put your sample in. You just send it back with oil (3 oz. or so) and $22.50. A couple days later you get the results. |
If anyone missed it, my oil level is also rising. This change it was about 1-2cm above the F mark on the dipstick. FWIW, I don't have an OMP.
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Oil control rings can definately contribute to the problem. As well as bad sideseal clearance. A rich tune/flooding can contribute as well.
On turbo cars this is very common, due to positive manifold pressures and richer mixtures under boost. |
Originally Posted by nik
Oil control rings can definately contribute to the problem. As well as bad sideseal clearance. A rich tune/flooding can contribute as well.
On turbo cars this is very common, due to positive manifold pressures and richer mixtures under boost. |
It's normal for some gas to get in the oil no matter what, but this sounds like more than normal for a non turbo. I don't remember if you said it was ported or not, but some porting styles can contribute to this(the ones that go into the oil control rings).
I wouldn't be too worried, maybe consider running a higher quality oil and change it more often. I change every 5000 km and run mobil 1 15W50. Mine comes out black and smelling like gas every time, as does most turbo rx-7. |
Originally Posted by nik
It's normal for some gas to get in the oil no matter what, but this sounds like more than normal for a non turbo. I don't remember if you said it was ported or not, but some porting styles can contribute to this(the ones that go into the oil control rings).
I wouldn't be too worried, maybe consider running a higher quality oil and change it more often. I change every 5000 km and run mobil 1 15W50. Mine comes out black and smelling like gas every time, as does most turbo rx-7. |
Originally Posted by My5ABaby
Blackstone Labs. http://www.blackstone-labs.com/
They'll send you a free "kit" to put your sample in. You just send it back with oil (3 oz. or so) and $22.50. A couple days later you get the results. |
1 Attachment(s)
Here's another comparable. Engine has 70K original miles on it. Good compression. Not raced as Blackstone states, but run at a half dozen track days a year. They misinterpreted my comments on the sample submission form.
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