GC, 4k miles, '07 Mini Cooper S

[johne123]

This is test #2 on a still breaking in motor. First test at 5k on the motor and oil is here

Results from HOPenn:
3-23-08 3-12-07
GC 0w30 BMW 5w30
Cu 13 49
Fe 32 69
Cr 1 1
Al 25 81
Pb 0 2
Sn 0 0
Mo 82 507
Si 14 66
Na 7 20
K 3 6
Ca 2041 2199
Mg 597 1314
Zn 1246 1742
B 8 48
P 1024 1488
Ag 0 2
Ba 0 1
Ni 1 1
CD 0 0
Ti 0 0
V 0 0
Mn 4 14
ST - -
OXI - -
NIT - -
SUL - -
W NEG NEG
A NEG NEG
VIS 11.3 9.8

So obviously there was nothing to worry about. I think perhaps most people are used to seeing initial UOA on very low mileage engine whereas I waited till 5k. I don't know why. Anyway, looks much better this time around.

 

[glennc]

Glad to see it has settled down so much. I was very curious what this next UOA would look like. For the record there are plenty of 5k+ break-in UOAs with very low numbers: these engines do seem to do more breaking-in than most. Al and Fe are still quite high but seeing the trend I'd say they're fine.

 

[johne123]

Yep. All the more reason to monitor oil temp. I'm working on an adapter for the temp sensor right now.

 

[RI_RS4]

This engine has cast iron sleeves and sintered steel crank bearing inserts in the aluminum block. I'd monitor Al closely, since there should not be much wear once the engine is broken in.

 

[RI_RS4]

Quite an interesting engine design:

Quote:
Ease of service and an appropriate maintenance concept were essential features in determining the engines' specifications. Depending on running conditions and the driver's style of motoring, oil service intervals will be approximately 30,000 km or 20,000 miles.

New Mini engine

 

[johne123]

Originally Posted By: RI_RS4
This engine has cast iron sleeves and sintered steel crank bearing inserts in the aluminum block. I'd monitor Al closely, since there should not be much wear once the engine is broken in.


So if we had to guess, is the relatively high aluminum from the block and the inserts getting used to each other? They also mention composite camshafts. I'm guessing perhaps the steel lobes are maybe pressed onto an aluminum shaft? Maybe that's where the AL is from. I don't know for sure the two materials for the cams are steel and aluminum, just guessing. Looking through my oil fill hole, the two materials look different, but I can't tell for sure.

 

[RI_RS4]

Good question. Could be the composite camshaft. It would be nice to know how it's built. I'd say just keep doing what you're doing and follow the Al/Fe/Cu curves on down. Use them to guide when the engine is fully broken in. Until then, I'd keep with relatively short OCI's to keep flushing the metals out. Also, given that Mn is running high, I suspect that you have quite a bit of fuel dilution, so Fe may never drop to really low levels. Either that, or there are some Al/Mn or Fe/Mn alloys in the engine.