Oil analysis

[Evgeni]

Just thought I would post up my oil test results. I am going to get some test done to see what the oil looks like at each drain interval and I will look at extending the drain if I can.
Car is an AU series 3 with an impco after market LPG system. It is run mainly on gas. ODO reading is 324683kms at the time of change.
Oil used was Penrite 15w60 changed with 15181kms on it.
Pretty impressed, especially with a TBN reading of 9.9. I could have kept it in for another 15000km!
Not to worried about the fact that they flagged the viscosity - it actually lost some viscosity over the drain period. The Penrite spec sheet says the virgin oil should be 184cst @ 40 degrees C and 25.1cst @ 100 degrees.

I've put Penrite HPR gas in at the moment so will post back after another 15000kms.


Viscosity @ 40 is at 147cst please check oil grade. Wear and contamination within acceptable levels. Continue to monitor.

Not sure what all of this means? Have a look at our Frequently Asked Questions

water
0

oxidation
13

lead
2

calcium
2700

nickel
2

iron
4

copper
3

sodium
3

molybdenum
10

boron
0

nitration
10

fuel dilution
0

chromium
0

zinc
1016

TBN
9.9

phosphorus
0

silicon
16

aluminium
8

FTIR soot
6.6

Viscosity at 100
19.9

magnesium
12

tin
3

Order Details

Make Ford
Model Falcon
Year Of Manufacture 2002
Number Plate/Equipment Id ----

[Mr Hardware]

Nice
I always had a sneaking suspicion that even the 14k oil change interval the gas taxis had was overkill.
It'd be interesting to see the results with a more commonly rated oil (15w-40 perhaps?)

[Evgeni]

I had the 15W60 in, simply because it was on special at Supercheap..lol
Seriously, I did not notice anything different in economy. I was getting between 11l/100 to 16l/100.
I am going to go down in viscosity and see what happens. HPR gas 10w50 is in at the moment and I manage to get some Shell HX7 10w40 for $20 which will go in after that. Once I get a baseline, I'll try and stretch things out. There are guys on the Bob is the Oil Guy forums getting close to 40000kms for petrol engines before the oil is looking bad.

I should point out that the car is a daily driver and gets driven like one. Nothing special other than it cant depreciate anymore.

Here is the link to the report where there is a facility to view what each of the numbers mean etc which people may find helpful.

http://www.roktex.com.au/sharedReport?published=532453

[pete05]

Whats the cost on having the oil tested?

[Evgeni]

It was $45 after postage. The company I used was in WA. I picked them because their test included a test for TBN without an extra charge.

[Jarry]

With the 100C viscosity readings, it looks like after 15,000kms, your oil only dropped one grade.... from 10w-60 to 10w-50.

That's a great result! Legend!!!

I think you've just busted the myth that Penrite oils are "sludgy" cos the Viscosity Index Improvers break down before the end of the service interval.


I'd be interested to hear what the lab's interpretation was of the soot reading? When I did an oil analysis on my bike the caution value for soot was 2.5....

[Evgeni]

The info on the soot reading from their website.

Soot determined by Fourier Transform Infrared (FTIR). Soot is a by-product of the combustion process in a diesel engine - a carbon residue formed from fuel air and moisture in the combustion chamber after ignition. Soot particles are held in suspension by dispersant additives in the oil preventing the soot particles from agglomerating (sticking together) and attaching to the rings, pistons and liners. These suspended particles are what turn diesel engine oil black. When too much soot is generated and the additives can no longer keep it suspended, deposits will form on the rings weakening the seal between the pistons and cylinder liners. Upper end wear to rings, liners and pistons begins and if not corrected, will eventually cause severe lower end wear to the main and rod bearings, crankshaft, camshaft, cam bushing and turbo bearing.

Unfortunately it doesn't give a ballpark figure of where it should be. Will do a search and see what comes up.

[Jarry]

Hey Evgeni,

I dunno if this helps as a reference...

This is the guidance I got through "Oil Check".

On the Right side of the table are the "CAUTION" values.

[Evgeni]

Hi Jarry,
Thanks for that. A reading of 6.6 for soot does seem high. I had a look at other analysis for both petrol and diesel and almost all of them dont register a figure. Although, the oil company didn't flag it, probably something to keep an eye on.
I ran about 700kms throughout the drain period on e10, so I am going to discount petrol as the cause. This then changes the belief or at least my belief that LPG burns clean.
It is likely the result of a lean condition. I note that I changed the O2 sensor when I did the oil change. I tested it and it was at ground voltage and unresponsive. I couldn't tell you how long it had been like that for.
My guess is that if the o2 was reading lean, the computer would have ran the car rich. Instead of producing CO2, it would have been spitting out CO and C which would equate to the soot reading. Hopefully, the O2 sensor change will drop this figure. If not, will probably have to play around with the mixer.
Maybe possibly some blowby as well at the km's I am at?

[Jarry]

Hey Evgeni,

My amateur theory is that while the oil is good to go further than 15,000kms... the filtration system is not.


In your shoes, I'd be considering: reducing the service interval, or, fitting a higher efficiency oil filter.... Or just not worry about it since she's a high miler.... but hey, where's the fun in that?!?


Purolator Pure One Oil Filters get a good wrap if you're chasing extended service intervals, but I guess it is mail order from the States, and who knows what the part number is???

There's a thread on it here. And some interesting (but bike related) stuff here.

I'd love to see a back-to-back on the soot reading with a better oil filter. The slightly elevated silicon reading could also suggest oil contamination, unless you've recently used some gasket goo on the engine.

[Evgeni]

I had a look at the high efficiency filters - all of them recommending a 5000km service interval. I might just stick to the good old ryco z9 for now and see what the next analysis will say.
Got this far with 15000km changes, so shouldn't be doing anything too detrimental. If it is, hasn't killed it yet.
Thanks for the info though.

[Jarry]

Good call....

You can't be wrong having done 325,000kms and still going strong!

Looking forward to the next test result with the HPR 10 GAS.

Interesting that the high efficiency filter manufacturers recommend 5000km intervals...

[Evgeni]

http://www.rycofilters.com.au/produc...igh-efficiency

I guess you can't have the best of both. Something that filters smaller particles will get filled up quicker. My concern would be a possible drop in oil pressure once the filter is at its recommended maximum.
15000 will come around in about 4 months so wont be long for the next test.

[Jarry]

Originally Posted by Evgeni

http://www.rycofilters.com.au/produc...igh-efficiency

Great link! Didn't realise these existed...

Yeah, good point about the trade-off in service life. The 5,000km service interval probably defeats the purpose. If you did the oil analysis at 5,000kms with a standard filter, everything would probably be perfect anyway.

Surely with its large volume, the Z9HE could go further than 5,000kms....

I guess one way to find out would be to cut open the filters after removing and compare.

Although, I've tried this before when breaking in a freshly re-built moto engine, but didn't have any luck... Couldn't tell the difference between swarf from the hack-saw and crankcase debris!!! FAIL!!!

[Jarry]

Originally Posted by Evgeni

My concern would be a possible drop in oil pressure once the filter is at its recommended maximum.

Once the oil filter chokes up wouldn't the oil just push through the bypass valve, and maintain oil pressure?

[Evgeni]

Originally Posted by Jarry

Once the oil filter chokes up wouldn't the oil just push through the bypass valve, and maintain oil pressure?

Yes, forgot about that lol

[Jarry]

You've sparked my interest on this topic, so I did some reading on the weekend.... Here's a page from the Bosch Automotive Handbook 8th edition...


My interpretation is (looking at the dotted line on Figure 5):
A high efficiency oil filter, like the Ryco Z9HE, may filter out soot better than the Z9, but it is still far from perfect.
If it gets 99% of particles > 20 micron,
then maybe it gets about 60% of soot (as opposed to an average filter which might get 30%???)...


I suspect also that the Z9HE filter media isn't very durable (to keep the pricepoint down to a level that the average enthusiast is able to afford), and this is what governs the 5,000kms service interval (not "filling it up with cr@p" like we thought). Meaning... go beyond 5,000kms at your own peril!!!


Apparently soot increases the viscosity of the oil. So you may have got a false positive on the 100C viscosity reading (i.e. the oil may have "broken down" more, but this is somewhat hidden by the elevated presence of soot).


Maybe this could be confirmed/denied with a 40C viscosity reading as well as the 100C?..... The importance being that the oil won't be flowing much at cold start-up if its viscosity at 40C has "thickened" considerably....but of course this would be purely academic after 325,000kms of trouble free motoring!!!!

[Evgeni]

Thanks again Jarry.
Ive' posted this in this forum as well
http://www.bobistheoilguy.com/forums...02#Post3647402

Just to get some opinions. Interesting reading anyway..

[Jarry]

Kewl!

Thank You...You're a legend for sharing!

Good pick-up that Phosphorus was zero. Could be a mistake with the high (good) Zinc reading?

If you're switching to 15w-40, Caltex Delo 400 (not the LE, not the gold) is an economical way to do it, buying in 20L drums.

The depot at Coreen Ave Penrith used to sell 20L drums for $85, but the private owners have gone and its up around $140 now. Poor.

Apparently you can still grab them cheap somewhere in Wetherill Park, but I haven't figured out where yet. Out of town depots like Kurnell and Port Kembla stock them cheap, but it's been a few years since I've checked.

A lot of dirt bike and 4x4 diesel dudes swear by this stuff, very different beasts - I know, but still thought I'd mention it.

[Evgeni]

I had a look at the Penrite spec sheet and it looks like alot of the Penrite oils dont have a high concentration of phosphorus. (anti corrosion additive). Seems to be a plausible finding.

I guess the zinc finding also reflects their marketing slogan of the oil having a "double layer" of zinc. Whatever double layer means...lol

$140 for 20l is still very cheap. If only I had room for a 20l drum. The joys of living in Sydney!

[Jarry]

Originally Posted by Evgeni

I had a look at the Penrite spec sheet and it looks like alot of the Penrite oils dont have a high concentration of phosphorus. (anti corrosion additive). Seems to be a plausible finding.

I thought the ZDDP (phosphorus) normally accounted for around 90% of the zinc ... until you step up to the "Racing" range where Penrite adds Boron as well.

Originally Posted by Evgeni

If only I had room for a 20l drum. The joys of living in Sydney!

Bummer... I feel your pain. It's hard to keep up an automotive hobby in the city with the most over-priced real estate in the world.

Originally Posted by Evgeni

I guess the zinc finding also reflects their marketing slogan of the oil having a "double layer" of zinc. Whatever double layer means...lol

Sounds like LIQUID ENGINEERING!!!
... now where have I heard that before??