This one was run for a short (distance-wise) interval of 4700km/13months on my "fun" car, a model year 1984 (built 1983) Saab 900 GLE. 2 litres slant inline 4, 8valve, single overhead camshaft, 118hp, automatic gearbox (= absurdly high rpm). Mechanic fuel injection (Bosch K-jet), no lambda sond/oxygen sensor.
Oil used was Mannol 10w-40.
When I removed the oil filter, I found this funny thing. It had somehow managed to get through the oil passageways and the oil filter flange, and was now sitting on the baseplate, above one of the entrance holes.
One side has a rough texture as pictured, the other is smooth and shiny. It is semi-brittle, that is it can be bend about 60-90°, before it breaks sharply. So no carbon, more varnish. Or both. Varnon. Carbish. Whatever...
The car has very low milage. I did this oil change at 125.020km (77,700 miles). This car has been neglected badly by the previous owner. When I bought it with 108.000km (67,100 miles), the engine was completely sludged up, the camshaft had seized in it's bearings and the timing chain was badly worn, in part due to the 1984 recall of the tensioner not having been done. (You can see pictures of the restauration here.) The engine has received a rebuilt head and new timing chain and gears but we did not open the bottom end - this is a bit of a hassle on classic 900, as there is no oil pan per se. The gearbox is under the engine, and the "oil pan" on a 900 is a just a depression in the gearbox housing. So we expected a lot of sludge and deposits to be there. The first OCI was extremely short, after only 1200km, the oil was pitch black, like in a diesel. From then on, 4000-6000km OCIs.
Here is what the dipstick looked like after 1000km on the first OCI after the rebuilt:
And here is the dipstick at the end of the current interval, after 4700km:
Now to The UOA. It is quite ugly, as was to be expected.
OIL Mannol 10w-40
MILES IN USE 2888 (4647km), 13 months
MILES 77700 (125020km)
SAMPLE TAKEN 17/05/05
FILTER: Champion C165
wear metals (mg/kg)
IRON 55
CHROME 1
TIN 2
ALUMINUM 10
NICKEL 1
COPPER 39
LEAD 65
MANGANESE 1
PQ-index 42
pollution (mg/kg)
SILICON 15
POTASSIUM 446
SODIUM 25
WATER (%) IR-GLYKOL negative
FUEL (%) 1.17
Additives (mg/kg)
CALCIUM 2387
MAGNESIUM 16
BORON 10
ZINC 1041
PHOSPHORUS 800
BARIUM 0
MOLYBDENUM 7
SULPHUR 3851
state of oil:
visc. @40°C (mm2/s) 84.47
visc. @100°C (mm2/s) 12.84
VI 151
OXYDATION (A/cm) 12
NITRATION (A/cm) 1
SULFATION (A/cm) 6
dispergency* (%) 91
SOOT INDEX** BN N/A
* the german word was "Schmutztragevermögen", hope I translated that right.
** the lab has introduced the "Rußindex", an in-house tool to check for soot in
gasoline oil, as soot from direct-injection engines will not show correctly in the
standard test for diesel oils
The comment translates: "A slightly elevated proportion of magnetisable iron particles can be detected via the PQ index. Iron and Aluminium higher than expected, given the short duration of use. Wear from components made of these materials such as as pistons (Al) and cylinders (Fe). Lead and copper drastically elevated, presumably due to bearing wear. Potassium unusially high. Normally no additive. Possible causes: entry of salts and bases. Slightly elevated fuel in the oil. Viscosity in the SAE 40 range. In case you have not done so yet, I advise to change the oil as soon as possible."
I presume potassium is from the lead replacement fuel additive (this car has an aluminium head without hardended valve seats).
Given the previous camshaft and chain failure and the slowly dissolving deposits, I expected iron and aluminium to be high. Lead and copper worry me a bit, though. This, too, might be accumulated wear during the neglect under the previous owner, that is only now being set free as the deposits are dissolved. Or the engine might indeed be eating itself alive.
I guess the only way to tell is to resample UOAs during the next several OCI. If there is a downward trend, the wear metals should all be "inherited burdens". If they stay the sme or there is an upward trend, I'll start to save for an engine rebuilt.
To help the bearings a bit, I chose Mobil1 5w-50 peak life for the next OCI.
The filter can be found here: https://bobistheoilguy.com/forums/ubbthreads.php/topics/4404210/Champion_C165,_4700km_(2900mi)
If you want to read more on the car, here are the two blog posts I wrote about the current oil change. Text is in german, but pictures are international, and google or bing translator might help with the words. If you have any questions, feel free to ask.
https://turboseize.wordpress.com/2017/05/08/ohne-maengel-oder-doch-nicht/
https://turboseize.wordpress.com/2017/05/11/ohne-maengel-wohl-doch-nicht-was-uns-das-oel-erzaehlt/
Lessons (to be) learned:
1.) I had no TBN measured, but from oxiation, nitration and sulfation and dispergency, the oil could probably have gone a bit longer, but wear metals called for condemnation.
2.) OCI have to be adapted not only to driving conditions, but also to the maintenance history of the specific car. Even with similar driving patterns, a 33% extended OCI can be very smooth sailing with a well maintained engine, while drastically shortened (cut in half!) OCI on a previously neglected engine can be borderline long.
3) even one of the cheapest mineral 10w-40 available in Europe has an add pack that is powerful enough to do a decent cleaning job -
and to dislogde deposits. (ACEA A3/B3)
4) Beware of low mileage cars owned/driven by females.
Oil used was Mannol 10w-40.
When I removed the oil filter, I found this funny thing. It had somehow managed to get through the oil passageways and the oil filter flange, and was now sitting on the baseplate, above one of the entrance holes.
One side has a rough texture as pictured, the other is smooth and shiny. It is semi-brittle, that is it can be bend about 60-90°, before it breaks sharply. So no carbon, more varnish. Or both. Varnon. Carbish. Whatever...
The car has very low milage. I did this oil change at 125.020km (77,700 miles). This car has been neglected badly by the previous owner. When I bought it with 108.000km (67,100 miles), the engine was completely sludged up, the camshaft had seized in it's bearings and the timing chain was badly worn, in part due to the 1984 recall of the tensioner not having been done. (You can see pictures of the restauration here.) The engine has received a rebuilt head and new timing chain and gears but we did not open the bottom end - this is a bit of a hassle on classic 900, as there is no oil pan per se. The gearbox is under the engine, and the "oil pan" on a 900 is a just a depression in the gearbox housing. So we expected a lot of sludge and deposits to be there. The first OCI was extremely short, after only 1200km, the oil was pitch black, like in a diesel. From then on, 4000-6000km OCIs.
Here is what the dipstick looked like after 1000km on the first OCI after the rebuilt:
And here is the dipstick at the end of the current interval, after 4700km:
Now to The UOA. It is quite ugly, as was to be expected.
OIL Mannol 10w-40
MILES IN USE 2888 (4647km), 13 months
MILES 77700 (125020km)
SAMPLE TAKEN 17/05/05
FILTER: Champion C165
wear metals (mg/kg)
IRON 55
CHROME 1
TIN 2
ALUMINUM 10
NICKEL 1
COPPER 39
LEAD 65
MANGANESE 1
PQ-index 42
pollution (mg/kg)
SILICON 15
POTASSIUM 446
SODIUM 25
WATER (%) IR-GLYKOL negative
FUEL (%) 1.17
Additives (mg/kg)
CALCIUM 2387
MAGNESIUM 16
BORON 10
ZINC 1041
PHOSPHORUS 800
BARIUM 0
MOLYBDENUM 7
SULPHUR 3851
state of oil:
visc. @40°C (mm2/s) 84.47
visc. @100°C (mm2/s) 12.84
VI 151
OXYDATION (A/cm) 12
NITRATION (A/cm) 1
SULFATION (A/cm) 6
dispergency* (%) 91
SOOT INDEX** BN N/A
* the german word was "Schmutztragevermögen", hope I translated that right.
** the lab has introduced the "Rußindex", an in-house tool to check for soot in
gasoline oil, as soot from direct-injection engines will not show correctly in the
standard test for diesel oils
The comment translates: "A slightly elevated proportion of magnetisable iron particles can be detected via the PQ index. Iron and Aluminium higher than expected, given the short duration of use. Wear from components made of these materials such as as pistons (Al) and cylinders (Fe). Lead and copper drastically elevated, presumably due to bearing wear. Potassium unusially high. Normally no additive. Possible causes: entry of salts and bases. Slightly elevated fuel in the oil. Viscosity in the SAE 40 range. In case you have not done so yet, I advise to change the oil as soon as possible."
I presume potassium is from the lead replacement fuel additive (this car has an aluminium head without hardended valve seats).
Given the previous camshaft and chain failure and the slowly dissolving deposits, I expected iron and aluminium to be high. Lead and copper worry me a bit, though. This, too, might be accumulated wear during the neglect under the previous owner, that is only now being set free as the deposits are dissolved. Or the engine might indeed be eating itself alive.
I guess the only way to tell is to resample UOAs during the next several OCI. If there is a downward trend, the wear metals should all be "inherited burdens". If they stay the sme or there is an upward trend, I'll start to save for an engine rebuilt.
To help the bearings a bit, I chose Mobil1 5w-50 peak life for the next OCI.
The filter can be found here: https://bobistheoilguy.com/forums/ubbthreads.php/topics/4404210/Champion_C165,_4700km_(2900mi)
If you want to read more on the car, here are the two blog posts I wrote about the current oil change. Text is in german, but pictures are international, and google or bing translator might help with the words. If you have any questions, feel free to ask.
https://turboseize.wordpress.com/2017/05/08/ohne-maengel-oder-doch-nicht/
https://turboseize.wordpress.com/2017/05/11/ohne-maengel-wohl-doch-nicht-was-uns-das-oel-erzaehlt/
Lessons (to be) learned:
1.) I had no TBN measured, but from oxiation, nitration and sulfation and dispergency, the oil could probably have gone a bit longer, but wear metals called for condemnation.
2.) OCI have to be adapted not only to driving conditions, but also to the maintenance history of the specific car. Even with similar driving patterns, a 33% extended OCI can be very smooth sailing with a well maintained engine, while drastically shortened (cut in half!) OCI on a previously neglected engine can be borderline long.
3) even one of the cheapest mineral 10w-40 available in Europe has an add pack that is powerful enough to do a decent cleaning job -
and to dislogde deposits. (ACEA A3/B3)
4) Beware of low mileage cars owned/driven by females.
Last edited:
