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I think I said, "what do you guys think?" I think that is exactly what I meant. So, lets hear it.
Although the amount went up, the actual quantity is still low so I wouldn't worry about it too much at this point. Iron, copper and lead are all low which is good.
Bearing wear normally shows up as lead at first and then copper when they fail. If all you did was hit the limiter a couple of times it probably didn't have much of an effect. Over revving on downshift is more dangerous as then it can go higher than the factory limit.
If you still have the filter and are worried about it you could try cutting it open. I've just started doing that and the results are somewhat enlightening.
Although the amount went up, the actual quantity is still low so I wouldn't worry about it too much at this point. Iron, copper and lead are all low which is good.
Bearing wear normally shows up as lead at first and then copper when they fail. If all you did was hit the limiter a couple of times it probably didn't have much of an effect. Over revving on downshift is more dangerous as then it can go higher than the factory limit.
If you still have the filter and are worried about it you could try cutting it open. I've just started doing that and the results are somewhat enlightening.
Thanks for the response. I could very well be wrong, but I am not sure there is a lot of lead in new(er) Mazda bearings, at least in the top coatings. My guess, only a guess, is that the actual composition has changed over the years. Manufacturers are trying to delete lead in bearing materials. Most of the new bearings I have purchased for other engines in the last couple of years have been advertised as lead free. These bearings were new Mazda installed by the previous owner, probably around 2015. Its not a lot, agreed, that is why I think it was a touch, that caused a smudge, since there was no real copper either. I am not concerned about the health of the engine just curious about the oil results, since I know I hit the rev limiter more than I had before on this engine, and it is not an engine that has anything better than factory spec balance. Yes, it is good to cut open oil filters. I also enjoy going full oil geek and looking at the last 1/8" of used oil in the drain pan on all the cars and bikes I work on in direct sunlight. Always fun to see how much metal is winking back at you.
Last edited by kevink0000; Jan 31, 2021 at 10:49 AM.
I changed the oil the other day before the new track season and decided to do all analysis just to see how the engine is doing. All looks good except a bit elevated chrome...
Last edited by Nadrealista; Mar 10, 2021 at 01:53 PM.
More info needed. But, yes, in my opinion that is a lot of wear metal for the mileage. 160ppm Fe at 5000km/3000 miles equivalent rate would be very concerning. The chrome is high too. How long was the last oil change interval before this one? Use patterns? Also, if the car has sat for a time , wear metals can show up high in the oil due to corrosion. That is what this looks like to me, actually. More backstory please.
Sure.
I bought the car which was sitting for 5 years (most probably no oil changes made).
The previous owner made an oil change after these 5 years to be able to move it and put it on sale.
The oil stayed in the car for 2.5 k km.
When I bought it, I changed the oil once more, then drove it for 485 km and changed it again. That's when I took the sample. It's from the first oil change I made to the car.
So it's now been two oil changes since it was sitting. I don't know if that's enough though as the car holds 7 lt of oil, not 4 that's coming out in every change.
Motor looks strong, compression at 7.1 and 7.2 (normalized of course) at the moment. No issues.
The car is being driven relatively hard. I always wait for it to be in temp though. Never redlined it while cold.
I didn't catch the 5k km equivalent part. Where did you get that number?
Thanks!
Sure.
I bought the car which was sitting for 5 years (most probably no oil changes made).
The previous owner made an oil change after these 5 years to be able to move it and put it on sale.
The oil stayed in the car for 2.5 k km.
When I bought it, I changed the oil once more, then drove it for 485 km and changed it again. That's when I took the sample. It's from the first oil change I made to the car.
So it's now been two oil changes since it was sitting. I don't know if that's enough though as the car holds 7 lt of oil, not 4 that's coming out in every change.
Motor looks strong, compression at 7.1 and 7.2 (normalized of course) at the moment. No issues.
The car is being driven relatively hard. I always wait for it to be in temp though. Never redlined it while cold.
I didn't catch the 5k km equivalent part. Where did you get that number?
Thanks!
The 5k equivalent is just my arbitrary effort to extrapolate that iron number over a normal 5k interval, as iron usually correlates well to oil mileage. Nothing scientific about it, just helps understand the number better.
I think that number will continue to go down since the most likely reason for that number is the fact that the car sat, probably in a high humidity/salt air environment. If its corrosion, its not nearly as bad as it would be if that was a genuine wear number in my opinion.
minimum acceptable (doesn’t mean it won’t run, just the make/break acceptable minimal performance value by the manufacturer that would rather not replace an engine under warranty) is about 6.8 @ 250 rpm or so
The 5k equivalent is just my arbitrary effort to extrapolate that iron number over a normal 5k interval, as iron usually correlates well to oil mileage. Nothing scientific about it, just helps understand the number better.
I think that number will continue to go down since the most likely reason for that number is the fact that the car sat, probably in a high humidity/salt air environment. If its corrosion, its not nearly as bad as it would be if that was a genuine wear number in my opinion.
Oh I see. I truly hope you are correct and I'm going to verify that in 5 months time when I'll do the next analysis.
I thought I had a really bad fuel dilution problem but I'm thinking maybe I'm getting more premix than fuel into the sump somehow based on this report.
Anyone have a thought as to where the tin might be coming from without the other common wear metals?
Curious to get your ideas. I just did a UOA for the first time in a long while, and lead is up. Not sure what to make of it, on the one hand its up, on the other the PPM is still low... you can see Blackstone's comments there. Anyone else seen lead increase like this and what came of it?
Bit of background: since covid and then my kid arriving, my driving patterns changed a lot. Many short trips, lower mileage (~1500km / year), no more track time. I *thought* I was using LiquiMoly 10w40 or 10w30, but based on this my shop might have switched me to something else without consent.
check the receipt from the shop. It’s very possible the tech saw 5w20 on the oil cap and poured that in, cause there’s NO WAY a 10w40 sheared down like that, especially with such low mileage. The extra wear is probably from dry starting it after storage and the short trips. Nothing you can do except monitor it during the next analysis. 🤷🏻♂️
Originally Posted by Loki
Curious to get your ideas. I just did a UOA for the first time in a long while, and lead is up. Not sure what to make of it, on the one hand its up, on the other the PPM is still low... you can see Blackstone's comments there. Anyone else seen lead increase like this and what came of it?
Bit of background: since covid and then my kid arriving, my driving patterns changed a lot. Many short trips, lower mileage (~1500km / year), no more track time. I *thought* I was using LiquiMoly 10w40 or 10w30, but based on this my shop might have switched me to something else without consent.
I agree with Fiji, That looks like a 20w and a weak one at that, or a diluted 30w. The formula is definitely SP looking with the low calcium, so that’s different also. I believe you found your answer. Is that 1700km? Lots of iron for that time also I think. Some of this could be corrosion related.
I saw bearing wear go up recently when I switched to a weak, cheaper more available oil thinking the viscosity was what mattered. I was wrong. The viscosity was low, there was low flashpoint, and there was lead and other bearing material. This was with 20w50. I switched to a robust 20w50( VR1) and got the best results I had seen. I will post the UOA when I can.
Happy Father’s Day BTW!
Last edited by kevink0000; Jun 16, 2024 at 09:15 PM.
Am I reading that correctly, blackstone is recommending a 1,700km interval due to your viscosity dilution? I also use Valvoline VR1 20w50 like Kevin does, but I have never gotten a UOA.
Am I reading that correctly, blackstone is recommending a 1,700km interval due to your viscosity dilution? I also use Valvoline VR1 20w50 like Kevin does, but I have never gotten a UOA.
UOA
My UOA is in this somewhere, but it says that the Mobil1 0w40 thickened slightly to 14.5 when it should have been approx 12 cst. I guess after 7 years you'd expect that. Blackstone can analyze them they just can't understand em.
You can never keep gas out of oil by changing, just drive with thicker oil and heat it up
Am I reading that correctly, blackstone is recommending a 1,700km interval due to your viscosity dilution? I also use Valvoline VR1 20w50 like Kevin does, but I have never gotten a UOA.
I think they're suggesting an equivalent interval to the last fill, which aged out with time rather than mileage. Which is probably what will end up happening. At my new normal annual mileage it'll be a few years before I hit my usual change interval of 8000km.
Fuel and water fractions are still low so it's not dilution, it sounds like I was filled with a different oil than what I asked for.
I think they're suggesting an equivalent interval to the last fill, which aged out with time rather than mileage. Which is probably what will end up happening. At my new normal annual mileage it'll be a few years before I hit my usual change interval of 8000km.
Fuel and water fractions are still low so it's not dilution, it sounds like I was filled with a different oil than what I asked for.
Blackstone does not measure fuel dilution well, it's an extrapolated figure only, based on flashpoint. . The flashpoint is pretty low, there is fuel, but it is definitely a different oil.
The UOA from 6/19/23 at 41k miles was the one I was talking about.
The final 2 are VR1 20w50. All of these are 20w50. The one with the high lead was Walmart ST. The rest are GTX 20w50 SP.
I had thought that the Mazda rotary bearings were happy as long as there was sufficient PSI and oil viscosity. The difference with the VR1 was unexpected.
GTX had been getting more and more weak with an anemic add pack and I thought switching to the cheaper ST was an easy move. Wrong, I was.
This is a rebuilt engine with all used bearings, rotors and shaft.
Last edited by kevink0000; Jun 18, 2024 at 07:17 PM.
