I hear of high lead in engine oil expressed in terms of PPM. However what numbers represent high lead levels? I recently had a UOA from Blackstone that indicated high lead of 34 PPM. I saw a document (actually from this site) that indicated that 40-100 ppm of lead was acceptable. So I am confused.
What is high lead in used engine oil-definition?
- Thread starter Russell
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IMO,
34 makes me wonder but not lose sleep
>60 maybe lose sleep
34 makes me wonder but not lose sleep
>60 maybe lose sleep
Depends on miles.
Depends of additives, fuel, engine (bearing making up, history), etc
If all those are factored out, then I change my Depends.
Depends of additives, fuel, engine (bearing making up, history), etc
If all those are factored out, then I change my Depends.
Yeah it's not an easy thing to generalize. Lead can be chemically leached out and give large PPM but not much mass loss or gouged out and produce low PPM but large mass loss.
Hey JAG, can you give us a quick run down of what areas of the engine will leach out Iron, Copper, Aluminium, and Lead?
Iron and aluminum don't really leach out like copper and lead can. Various bearing materials in the engine may use metals alloys of the brass/bronze/copper/lead type. Oil coolers usually use copper.
My UOA of a Green/Gold blend of GC threw a high lead reading in my 04 Tacoma 2.4l. I "may" have used a fuel system cleaner at the very beginning of the OCI but I don't remember. There are enough good UOA's of GC out there but I am still a tad concerned about mine.
I'm guessing Iron comes from piston rings, and if you're saying Brass/Bronze/Copper/ and Lead come from the bearings, where does the Aluminium come from then?
Piston rings usually chromium but in rare cases can have iron in them too.
Aluminum is mostly from pistons and in rare cases from cylinder walls on some high end European cars.
Iron is in most engine parts and are too many to list.
This info is on www.bobistheoilguy.com main site...go to one of the links.
Aluminum is mostly from pistons and in rare cases from cylinder walls on some high end European cars.
Iron is in most engine parts and are too many to list.
This info is on www.bobistheoilguy.com main site...go to one of the links.
Thanks JAG
I once saw a listing on the net (sure wish I had bookmarked it) and I think it said up to 60 ppm lead is not a worry. I once had 476 ppm lead!
Whole story is in the UOA section. OCIs went 476, then something like 135, then about 30. Was apparently dirt ingestion on the initial OCI.
Very Old school individual wear metals under 100PPM No big deal.
Over 100 ppm oil change time.
bruce
Over 100 ppm oil change time.
bruce
Lead is bearings? correct?
Forgot to state, I used Techron Fuel injector cleaner and Valvoline Synpower fuel injector cleaner on the last two tanks before sending in my oil sample. I also use Chevron 93 most of the time. BTW my copper, iron were not elevated.
I was expecting this question to get a lot of opinions as we are often found debating over just a few PPM and questioning the effectives/suitability of the oil in question/use
.
seriously though, like others have said, one value from one engine to the next can mean different things and have various degrees of impact on the serviceable life of the components/engine in it's origional build.
I could only think that an element such as lead would be found in bearings to various percentages due in part to it's strength or lack there of, which makes it a good sacrificial substrate that can be serviced without high expense and resource. Heck, even I have changed-out bearing inserts though at the time it might not of been neccessary (educational/recreational rebuild). Some cases however as far as sacrificial bearing surfaces are concerned, lead may not even be present, and bearing inserts might be eliminated all together as in the case of some cam assemblies where the cam is held in the machined surfaces of the cylinder head itself.
My knowledge is rather distant, recalled from what little first hand accounts I have and vague recollections of my readings. Heck, I was shocked to have read the other day in a topic somewhere on this site where the military has contaminent or wear limits in the 100's PPM. Their attention is in part else where, as long as the machines can perform when needed in service, and things getting rebuilt/replaced back on base. A different sort of budget and duties for those in the service environment I can only imagine.
Take care everyone,
kid.
.seriously though, like others have said, one value from one engine to the next can mean different things and have various degrees of impact on the serviceable life of the components/engine in it's origional build.
I could only think that an element such as lead would be found in bearings to various percentages due in part to it's strength or lack there of, which makes it a good sacrificial substrate that can be serviced without high expense and resource. Heck, even I have changed-out bearing inserts though at the time it might not of been neccessary (educational/recreational rebuild). Some cases however as far as sacrificial bearing surfaces are concerned, lead may not even be present, and bearing inserts might be eliminated all together as in the case of some cam assemblies where the cam is held in the machined surfaces of the cylinder head itself.
My knowledge is rather distant, recalled from what little first hand accounts I have and vague recollections of my readings. Heck, I was shocked to have read the other day in a topic somewhere on this site where the military has contaminent or wear limits in the 100's PPM. Their attention is in part else where, as long as the machines can perform when needed in service, and things getting rebuilt/replaced back on base. A different sort of budget and duties for those in the service environment I can only imagine.
Take care everyone,
kid.
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