stuartph

Hi Guys


I had a sample of my engine oil test (motul 15w50 syn ) and here is the test result they mailed me.

What do you guys think i should do as my car is boosted should i pull the engine or just carry on changing it and regular times, this oil sample had no more than 3000 miles on it and has always been changed well before its due.


Unit ID No. PORSCHE

Description. ENGINE

Make. 928GT

Model.

Location. STUART


Oil in use. 15W50

Sample P086064-001 Report Date: 04/11/2008

***Early Warning***Early Warning***Early Warning***Early Warning***Early Warning***

Symptoms: Note levels of: Tin and Silicon.:

Diagnosis: Indication of possible component wear.: Possible lubricant contamination.:

Actions: Change Oil & sample at regular intervals

Sample ID P076394-001 P086064-001

Sequence Number 1 2

Date Sampled 06/12/2007 21/10/2008

Date Received 10/12/2007 29/10/2008

Test Date 12/12/2007 3/11/2008

Unit Life

Oil Life

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Status CAUTION

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

PHYSICAL - PROPERTIES

Viscosity @ 40c cSt 67.3 83.1

Water %wt 0.0 0.0

TIM % 0.3 0.1

SPECTROCHEMICAL - ANALYSIS

Iron mg/kg 36 8

Chromium mg/kg 2 8

Aluminium mg/kg 13 17

Molybdenum mg/kg 56 652

Copper mg/kg 44 5

Lead mg/kg 4 1

Tin mg/kg 5 42*

Nickel mg/kg 0 0

Silicon mg/kg 16 30*

Sodium mg/kg 5 6

Boron mg/kg 115 18

Vanadium mg/kg 0 1

Calcium mg/kg 2049 1286

Phosphorus mg/kg 694 919

Zinc mg/kg 891 960

Magnesium mg/kg 178 859

Barium mg/kg 1 0

Vlocity

Stuartph,

I'm having trouble understanding the parameters. The kits that I use state values in Parts Per Million. So, I'm not sure how far out of the normal range you are with your tin and silicon. If you still have the filter, I would recommend that you cut it a part and see if you find anything in the pleats that would indicate a problem.

To help you understand the sources in the engine for tin and silicon, in general terms.

Sources for Tin are: Journal bearings, Bushings, Oil Pump bushings, Thrust Washers, Wrist Pin bushings.

Sources for Silicon are: Coolant additives, Gasket Materials, Housings Castings, Ingested Dirt.

It looks like your trend for some of the other Engine Wear Metals are also heading up....Iron, Chromium and aluminum.

Someone else may be able to chime in with specific wear items for our engines based upon your results.

At the very least, I would change oil and filter and do another analysis in 1500 miles.

Is this vehicle an automatic or a 5 speed?

Good luck and if you have the Normal- Abnormal - Excessive ranges for your elemental interpretation, be sure to post that.

Ken

MrGST

I'm no expert but if the engine is running ok, I would do another UOA at the next change interval and see if the results are the same. If so, then try a different oil and see if the results change. Tin would indicate bearing wear, correct? And silicon is probably from the bores.

Maybe try a 0W or 10W-40 and note results. Depending on what the UOA shows, maybe try 10W-60...but use the UOA as gauge.

Btw, what type of use does the car see? Short commutes or long high speed runs?

ShawnSmith

Tin. Bearings. be cautious.

ask my old e46M3 how I know

stuartph

Thanks for the replies so far guys


Its a GT thats got a murf stage 3 on it

Yes it is driven hard sometimes but not always

Could this be the start of 2/6 failure ?

BC

detonation causes undue rod bearing wear.

jpitman2

milligram/kgm = parts per million. I dont follow the two numbers - usual show is this sample, then typical. Above they look like typical, this sample, eg Tin mg/kg 5 42*
I did one recently, after a lot of intermittent use, and it came back with a caution - high lead (51) and possible fuel contamination. Doug Hillary looked the results over, and said he saw nothing to be overly concerned about, but change and retest in 2000kms, which I am working on.

jp 83 Euro S AT 51k

Vlocity

I wish Doug would drop in and take a look at the results, he would be able to give a definitive answer, while I'm just trying to be helpful.

Ken

stuartph

Ken

Yes i wish doug would show up

I think i might try one more oil change in a few months but in the meantime start buy parts and a cross drilled crank etc

Vlocity

Were you able to cut your filter apart and take a look?

I don't know what Doug's PM handle is....you might do a search under Oil analysis and check a couple threads for him.

I don't know anything about the Motul...I'm sure it's a good oil, but do you know what the ZDDP additive levels are.....you might want to find an oil with a high level. What I'm using is 1575 PPM Zinc / 1424 Phos.

Regards,

Ken

Ken

mark kibort

amsoil racing oil has a lot of zinc in it now. 15-50 racing oil.

Of course we know of all the luck I have had with it. (both scot and I)
mk

stuartph

Ken


No i cant cut open the oilfilter i'm off qatar at the moment and wont be home till start of next month, i'll see if i can email motul and get that figure

Doug Hillary

Hi,
Stuart - It's always difficult to accurately comment on what really is a "single pass" UOA. So here are some comments on the wear metals, and I have assumed that the RH column is the latest UOA

Yours first my 928 database shown in brackets - then comments

Iron - 8 (9) - OK
Chromium - 8 (2) - OK
Aluminium - 17 (5) Monitor - Highest on my DBase is 15
Copper - 5 (6) OK
Lead - 1 (4) OK
Tin - 42 (NA) Monitor - Tin is rarely taken during a UOA

Other:
Silicon - 30 (7) Take action - Check intake tract for leaks - Has engine been apart recently or have any sealants been applied recently??

Chemical composition:
Unless a Virgin Oil Sample (VOA) (new oil) is taken it becomes quite irrelevant to comment unless a Total Base Number (TBN) or Total Acid Number (TAN) is obtained during a UOA

Viscosity:
Without a VOA it is difficult to be accurate but the viscosity (83.1cSt) seems "odd" for a 15W-50 synthetic lubricant

I note you are in the UK and also that the engine is charged. What Lab was used?

I would be inclined to do an oil change using a 5W-40 synthetic Heavy Duty Engine Oil (HDEO), or a mineral 15W-40 HDEO (such as Castrol RX Super) if the ambient temperature allows, and monitor it via a UOA after 2000kms and then subject to results, again after 4000kms

I hope this helps!

I have been asked by Randy V to update a previous Thread on Lubricants for the 928 - should I include a segment on the average/high/low results from UOAs from my database? What do members think??

Doug Hillary

Hi,
Ken - Your comments are noted. However many chemicals make up a lubricant's additive package. All of which is carefully formulated.

Many newer anti wear (AW) and other chemicals are outperforming high levels of phos/zinc and the UOA details shown here in Stuart's UOA indicate some of these - note the Molybdenum content of the Motul product (which I suspect to be the V300 version) for example and some others too. I can't go further as I don't have a VOA on the product.

Motul has a very good reputation and they make Porsche Approved lubricants (two 5W-40 versions are Listed) - but they are not the long sought after but unobtainable "magic elixer" either

UKKid35

I've not found anyone in the UK who would reply to my UOA enquiry. I'll try Motul, but I wonder whether they only do analyses on their own oil?