When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
It is going to be related to bearing wear, just which bearing ? Tin is used in white metal, I am not sure of any white metal in the S2000 engine so bearing overlay may be the source. There are also no solder joints to be a source, unless you have a coolant leak.
According to Wearcheck
Tin is frequently alloyed with lead to form what is known as Babbit metal (white metal) and is the major constituent of a plain bearing overlay. This is most commonly found in the main and big end bearings of engines. Some pistons may have a tin flashing on them; this helps to conduct heat.
Solder is also an alloy of tin and lead so any soldered joints may leach into the oil and this is sometimes seen with internal coolant leaks. It is not an indication of a problem but it can show up. Tin can be found as both a wear metal and a contaminant and on very rare occasions it is an additive in some specialty fire retardant lubricants.
It is going to be related to bearing wear, just which bearing ? Tin is used in white metal, I am not sure of any white metal in the S2000 engine so bearing overlay may be the source. There are also no solder joints to be a source, unless you have a coolant leak.
According to Wearcheck
Tin is frequently alloyed with lead to form what is known as Babbit metal (white metal) and is the major constituent of a plain bearing overlay. This is most commonly found in the main and big end bearings of engines. Some pistons may have a tin flashing on them; this helps to conduct heat.
Solder is also an alloy of tin and lead so any soldered joints may leach into the oil and this is sometimes seen with internal coolant leaks. It is not an indication of a problem but it can show up. Tin can be found as both a wear metal and a contaminant and on very rare occasions it is an additive in some specialty fire retardant lubricants.
Very interesting. Save for the different oil used, the only other added variable that I haven't mentioned is the addition of a fuel additive "Fuel Doctor" (Australian Brand) that claims to be a:
- Fuel Stabiliser
- System Cleaner
- Upper cylinder lubricant
I do not know what the elevated tin means from a practical perspective (i.e the extent of bearing wear, if any). I was not alarmed by the very few flecks in the vtec screen.
I suppose the only way forward is do another UOI on a short interval and hope that tin is trending downwards. If not, I suppose the pan needs to come off and bearings will need to be inspected.
I would be alarmed at metal flecks in that screen until I knew what they were and remedied. At best you have metal contaminants floating around your oiling system which will cause other wear. At worst you have a bearing failure in progress. You should not have metal flecks in your oiling system on a healthy engine. You have an oil analysis showing high levels of tin and visual confirmation you have some sort of metal (assuming it is indeed metal) in your vtec screen, which sure looks to support the high tin levels in your oil analysis. You also have input that tin is mostly used in the bearing overlay surfaces. Seems to me its time to drop the pan and inspect bearings. You can fix it then before a bearing fails/spins and trashes the motor (which by the way costs and arm, both legs and a left nut to purchased used). Seems to me some caution is a good idea, but it is your gamble to make!
Have you cut open the oil filter from your last change? If I were finding metal in the VTEC screen I would do that for sure and look for more.
I doubt you are seeing any negative effects for additives, but in general I will add zero additives to anything my cars. Good mechanics I know also feel this way. No oil modifiers (decent quality oil is fine and requires no modifiers) and certainly no fuel additives. Most times they do almost nothing and are just one more variable. The only time I have every varied from this is if I am cleaning the fuel system. BG44k is the only thing I will run through my fuel system as it actually DOES clean pretty well. But that is something I may do every 50,000 miles tops. Up to you if you want to run those and all sorts of special oils, but mfgr recommended weight oil of decent quality (synthetic is good if you are taking advantage of longer service intervals which is most of its purpose) and clean fuel is all you need.
Hi all, I forgot to update this thread - I did another UOA with some "HKS SUPER OIL" that I picked up on sale plus a potassium borate based additive (archoil 9100). Wear numbers reverted to normal levels.
Its been relatively smooth sailing with my S2K of late - Plenty of track days, zero oil burn etc.
To my surprise, I have received another UOA with an elevated number - this time, Lead - all my UOA records are in the picture below (You will see this includes my initial query regarding Tin and everything in between)
We can observe that lead has increased from 2ppm to 7ppm and then to 24 ppm. I'm starting to think that this could be a bearing progressively eating itself (perhaps caused by earlier damage?) and I'm keen on thoughts. (Prior to receiving the result I had one track day, with no issues and that track day oil is still in the car).
Further, I cut open the oil filter - It was pretty clean (I ran this filter for 2 oil changes) - with one weird 'flake' - almost looked like very smooth aluminium foil:
I'm keen on opinions regarding where I should go from here - The engine feels healthy, burns no oil and has been treated to Group IV/V oils in my ownership, with the oil changed excessively.
Should I pre-emptively replace the bearings whilst (we assume) the crank is still good? Should I inspect and replace the bottom end bearings only; or the mains as well?
If those lead readings are correct then I guess you will have some form of bearing failure in the near future. The issue is that the bearings can just puke on you out of the blue with no warning sign, even if just driving down the road on a gingerly drive. Once they suffer some damage it can manifest itself later down the road and then it all goes bad fast. The best course of action is to replace the bearings but it could be main bearings and rod bearings we are talking about, we just don't know. An increase in tin could also be the thrust washers if they are starting to fail too. I had a motor fail a few months after a high lead reading on my UOA, despite the motor running perfectly, and it happened on a simple drive down the road from my home. When it happened it happened without warning.
Last edited by zeroptzero; 03-03-2023 at 01:03 PM.
I will 2nd this with a if the lead SPIKED then I would not drive it much and definitely not track it till bearings are checked. Even if it's crank bearings only that you change without taking the entire engine out. Definitely replace the thrust bearing too while in there.
06-10-2020, 05:18 PM
