Millers oil report

Just received this back from Millers. Would short journeys and moving the car in and out from garage cause the fuel dilution ? Anyone care to comment on the rest of the findings, everything look okay ?

Was it Millers oil you are using? Mine was the same with the high Mo levels but the oil they use has this. How long had the oil been in the car? Ive heard that the annual change regardless of mileage is worthwhile due to this dilution with the fuel. Any concerns phone them up and they are spot on to speak to.

Hi I always believed that frequent short journeys from cold will cause accelerated wear from petrol washing the bores and water condensation inside the engine. It would not surprise me if the excess petrol from a cold running engine might thin the oil. But thats just my belief. Berni

A cold engine needs a richer mixture to compensate for fuel that will condensate on the inside of the inlet tracts.The consequence of this will be fuel dilution of the oil.

Thanks all. It was Millers that was in it. Mileage on oil was probably around 3k when tested but I have to admit I didn't change it last year due the low mileage, probably only had 1k on it when I taxed the car last April to start using so I didn't think it was worth changing oil. Don't think I'll do that again, I'll just change yearly regardless. In and out garage and short journeys makes sense.

If you email them the lab guys at Millers are happy to answer any questions you have about the data. The chap was very helpful with me.

If that oil only had 3k miles on it, I'd suggest that some of the wear metals are looking potentially high, aluminium in particular which could point to pistons / cylinder liners. High silicon could also be from cylinder liners. Copper is also high which normally would indicate bearings but you'd expect to see lead with it, which is coming out at zero. So could be down to something like copper grease? Iron also a little on the high side maybe. How many miles on the engine? IMS done, checked for bore score?

He's got a fresh rebuilt engine. A diluted oil may have less friction reducing properties leading to more wear metals??? All looks fine and report says good engine in decent condition. Change oil and drive more often for longer. Ie get out and enjoy it. (In a few years we might not have this option)

Guys, just a word of caution on this. The unburnt fuel diluting the oil is condensing on and washing away the oil coating the bore walls (petrol is a very effective degreaser) and finding its way into the sump. This leads to unlubricated / unprotected cylinder walls during startup. More frequent oil changes will not solve this particular problem. You've really got to run the engine until startup /cold run enrichment stops and all the fuel is burnt off (whenever that is!) before stopping the engine. I only use the car if I know it will get up to full operating temperature to guard against this.

Totally agree. This is why starting and running the engine from time to time while a car is laid up is a bad idea (IMHO). Unfortunately it's even worse with a boxer engine as gravity also plays its part allowing fuel on the cylinder walls to 'wash" to the lower length of the cylinder rather than be evenly distributed.

Millers CFS oils have a ton of moly in them, too.

Ah ok on a fresh built engine you would expect higher results from the parts just bedding in. I'd suggest getting this analysis done annually to keep an eye on things

Thanks all for the input, as James mentions it's not long been rebuilt so I thought getting the oil checked would provide a good benchmark. I was just a little concerned about the oil dilution but this has been my own doing so I'll think twice about starting car for short periods of time and I'll be changing oil annually regardless of mileage.

Interesting comparison with mine, which is on 118k

To bring this back to life. I've had my 2nd report from Millers albeit with very little mileage on the oil this time but what miles that were done were covered on a road trip so no stop start journeys or idling up my drive this time. My concern is the fuel dilution again, does this point to there being a problem with the car some where. I know fuel in the oil is not a good sign.