Mobil 1 0w20, 7900 miles Subaru 2.5 na, dust leak

[oilyriser]

engine has over 100,000 miles, oil filter Fram XG with the wire mesh backing. Air filter was STP made in Israel. Replacement identical but Purolator brand.

Pb 6
Cu 1
Cr 1 (previously 0)
Fe 17 (previously 7 after 5500 miles)
Si 13 (prev 10 after 5500 miles)
Na 15

moly 95, zn 788, p 759, mg 11
visc 8, TBN 3 (pretty good for that long and over winter)
nitration flagged as elevated, no fuel, glycol or water


Drain plug magnet showed excess iron. Air filter leaking slightly in a couple of spots at the clamshell hinge side of the housing, where pressure is not maintained by spring clips. I won't leave the filter in for this long (58,000 miles) now that I know the filter housing is unable to maintain pressure against the seal as the seal ages and shrinks. Filter is difficult to replace due to clamshell housing design and lack of room to swing the clamshell.

UOA led to detection of air filtration failure as cause of excess wear found by drain plug magnet.

 

[buster]

I would have expected the wear metals to be much higher, espeically Fe.

 

[oilyriser]

Al - 11 ppm.

 

[buster]

Originally Posted By: oilyriser
Al - 11 ppm.


Missed that one. Al is high. Looks like RL.

 

[BlazerLT]

I highly doubt that a 3ppm increase is something that would contribute to an elevated amount of material on the drain magnet.

 

[shanneba]

The iron wear rates are close between samples.
5500/7= 785.71
7900/17= 790.017

I would expect a little higher iron/wear through the winter.
Good that you changed the air filter, I change mine at about 20,000 miles even though the schedule is every 45-50,000.

 

[buster]

Could be a case where the majority of the wear would not be detectable using oil analysis. Particles are larger. ??

 

[oilyriser]

Originally Posted By: shanneba
The iron wear rates are close between samples.
5500/7= 785.71
7900/17= 790.017



I get 465 for that last number.

Yes, the silicon did not increase per mile over the 5500 mile winter test, but there was a fair amount of iron on the magnet in that one, too. I'm hoping it is from the air filter leakage. I also hope the sodium is from road salt.

I should look for a different intake system that I could connect to one of those Donaldson power core filters. The dealer sells air filters for this car, but they're those cheap floppy ones that are impossible to properly install on this car without moving the engine forward an inch.

 

[oilyriser]

Update on my ongoing #20 experiment: Latest run of 6000 miles with Canadian Tire F1 5w20 conventional showed very little buildup on magnet. This is with the new air filter. Current fill is Canadian tire syn 5w20.

 

[OrdnanceMarine]

Sounds like you might have found the problem. Probably makes you glad you do UOAs?

 

[oilyriser]

I'm trusting the magnet, too. Two other cars had consistently clean magnets, but this one did not.