Castrol Tection 15w40, 3800 miles, Land Rover TD5

[landyman]

I am looking at buying this vehicle, and did an oil analysis on it. Herewith the results. The vehicle did have an injector leaking / cracked head problem before, but this has been corrected (new head, new injectors, seals etc.) and oil has been replaced 3800 miles ago.

The only worrying bit is the 2 % fuel dilution in this sample, but I don't know if that is a lot, and whether there was a lot of short trips done with the vehicle before I took the sample (I did drive it on the highway for 30 mins before the sample). I suppose there could still have been some trace amounts of diesel left in the system even after replacing the oil?

The question: Buy / not buy?

Diagnosis by Wearcheck:
"Wear rates are normal and the sample provided appears free from
unacceptable contamination or degradation. A microscopic particle
examination of particles filtered from the oil revealed no abnormal
contamination. Slight fuel dilution evident."

** Wear metals
Iron 26
Chromium 4
Nickel 2
Molybdenum 3
Aluminium 10
Copper 11
Tin 0
Lead 1
PQ Index 12

** Contaminants
Silicon 21
Sodium 5
Soot value 0
Soot % 0.0
Oxidation 12
Sulphate 18
Nitrates 7
Fuel % 5
Water % not detected

** Additives & Lubricant condition
Magnesium 15
Calcium 2863
Zinc 1166
Phosphorous 1024
Boron 2
Sulphur 11630
TBN 9.9

** Viscosity
cSt 40 degrees Celcius 84.3
cSt 100 degrees Celcius 12.5

 

[Brons2]

9.9 TBN? run it for another 3800 miles at least!

Silicon is high, maybe from RTV sealant if it's had recent work done.

Wear looks a bit on the high side but nothing catastrophic.

I think it's probably just as good as any other used Land Rover. I wouldn't buy it for that reason, but if you want a Rover, I'd say this one is probably OK.

 

[landyman]

I made a mistake - the fuel percentage is actually 2 %, NOT 5 % .

 

[dnewton3]

Fuel at 2% is reasonable; 5% would warrant an immediate change. Presuming the 2% is correct, I'd say it's OK if there has been a fair amount of idling.

The wear metals are not too bad, although not stellar. Howegver, it is not uncommon to see the wear metals spike a bit after a rebuild event so they would not worry me at all.

Normally the Si would be a concern, but I'm sure that is probably from the rebuild. Silicon from sealants and silicone from dirt are seen as the same thing in a UOA. Because the rework is so fresh, it's likely sealants and nothing to worry about.

I'd say this is worth investing in if the price is right.

 

[landyman]

I worked out: 7.1 litres of oil if changed "wet", and 8.1 litres if filled from "dry". Thus 1 litre of oil remains during a change. The vehicle had a fuel-in-oil issue before - and a 2 % dilution on the current 8.1 litres is approximately 162 ml of fuel. *If* the current fuel contamination is from the previous incident that would suggest the fuel dilution would have had to be 16.2 % - which would have been possible since the level on the dipstick rose quite a bit (according to the mechanic).

I think I will have the oil changed again, and do another analysis in about 2000km to check where we stand. If the contamination is the only source of fuel the next analysis should show < 0.5 % fuel dilution.

Makes sense?