Spike on copper and silicon on oil analysis

500 hours with gradually climbing copper on a big bore Lyc and a silicon spike
my first suspect is rocker arm bushings..
second is wrist pin bushing
third is contamination (more likely for the the silicon due to the spike) But changing a gasket, a dirty oil funnel, intake air leaks, oil additives, contaminated gas, etc. it could be anything...
Anyone putting some magic juice in the gas?

Yeah, it is worrying and annoying...
(which is why I do not do oil analysis on planes/boats/tractors/dozers/trucks/etc. - first off, I would go broke just from the analysis
personally, I would change oil to a straight weight 50, no camguard or other chemicals, and change the oil filter brand (yeah, I've seen it happen) and hammer 20 hours onto the engine and analyze it again... Go from that report...
 
peter-h said:
A little update:

There was a ~5mm gap in the alternate air intake door.

So plenty of air would have gone past the air filter.

Hopefully that explains the spike in silicon.

I am ~4hrs into the current oil and will probably change it at 15-20hrs and see if the copper is still there.

I cannot understand how one can get a spike in copper and not in tin. Are there really brass (copper+zinc) bearings in an engine? That would be a poor engineering material.
Click to expand...

Yep, wrist pin bushings, rocker shaft bushings, piston pin plugs, valve guides...
 
OK; here is an update from a sample taken 21hrs later.

The silicon has come down, and more importantly the copper has also.

The alternate air door did not get fixed until 2-3hrs into this oil sample, which perhaps explains why the silicon is still a bit elevated. Plus the residue from the oil oil, presumably.

I also asked them to analyse the oil filter element ($110 charge). I didn't see anything in there that was "shiny"; just the usual ash-like particles which did not get picked up by a magnet. At a stretch they could have been bronze (which is why I am paying the $110) but I have seen them before.
 
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Further update:

Just got the $110 oil filter analysis back.

It reports "normal" with traces of chromium and aluminium, and a lot of "grit".

So it does look like a lot of stuff got sucked in at some point, through the gap in the alternate air door...
 
N801BH said:
:idea:IMO..... The Silicon is your biggest event to figure out... Elevated Silicon levels will come from a mis aligned airfilter, no airfilter, sitting is a VERY dusty and dirty location, scat tube leaking from the air filter box to the induction and I have even seen a MX use a dirty funnel during an oil change and all the sand, dirt, crap are washed into the engine as they pour oil into the funnel...

The elevated Copper numbers might be a result of that Silicon sawing the motor apart....

I would drain the oil, change the filter, maybe even pour in a little mineral spirits to flush the case, add new oil and recheck after 20 -25 hours. If the numbers stabilize then you have dodged a bullet.. If the Copper and other numbers are still up then you might need a closer inspection...

Ps... it is possible someone put some sand in your engine so loook VERY close at the dipstick tube to see if there is any sand / dirt in it... Unless they were very careful remnants of that sand/dirt will be embedded in the threads where the dipstick screws in.. :idea:
Click to expand...

Glad the "event" was not too bad in the long term life of the motor.
 
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