Oil Wear Metals Analysis

[pmoloney]

I wondered if anyone else (other than me!) samples their oils after racing to monitor trends in wear metals, contaminents etc and indicate if there's a problem before failure?

I'm setting up in business offering this service and have noticed that this seems to be something that is little practiced in UK motorsport even though we are using highly tuned engines, gearboxes, diffs etc.

[Larry J-Croft]

As an ex military helicopter pilot and engineer, this is something we routinely did with aero engines and some transmission componetns. What are you going to measure? If it is just debris from filters, that only tells you so much and my hewland gearbox is always full of the stuff!! Or are you looking at SOAP and other more sophisticated techniques?

[pmoloney]

Hi
Depending on where the sample is taken from (engine, gearbox diff etc), the tests that are used include, wear metal analysis, PQ's, water, fuel, antifreeze, viscosity, IR, magnetic dip test & particle count. It's a very thorough process with interpretation of the results and a detailed red/amber/green report output with comments.

Regular sampling (after ever outing normally) will allow the lab to plot trends and effectively warn when something is going wrong.....with the intention of catching any abnomolies before any major failure occurs. At £17.50 a sample, it's well worth the investment to save an engine or gearbox before something gives resulting in major damage...and expense!

[Al Weyman]

I have an aircraft screen filter on the dry sump system I bought from the states to go on a car I am renovating, I understand they use this a lot in the US and open it up to inspect for debris also I think a lot of the drag race boys overhere use the system. Sounds a good idea to me.

[pmoloney]

Sounds like a good system, but I doubt looking for particles in the oil by eye will allow the mechanic to catch a failure before it happens. The damage will be pretty advanced by the time particles are visible.

Oil sampling looks for microscopic wear metals (<10 microns) which identifies a problem long before the particles are visible to the naked eye and allows you to save components much earlier if there is an issue.

[graham bahr]

pmoloney, ive never done it but it seems a good idea if you can get it done relativley cheaply, but a couple of questions,

how do you tell the differnce between particals in the oil from running/bedding in and wear? or should you only analyse oil from a well run in motor so you can plot the increase? or maybe plot the growth of such particals, followed by the diminishing as all the bedding in is done, and then just moniter it until such times as the amount rises again?

how many sumps have we all looked in and been frightened by the amount of metal etc in it, only to tear down the engine and find it in perfectly good shape?

one thing i cant help with though is fatigue failures! like BMW rocker arms!

[ss_collins]

Can you PM me some more details about this...

[pmoloney]

Hi Graham
I did it all of last year and it was fascinating to see the results change and relate to the running of the car. The lab will highlight any issues with the results in the report. Cost is not too big a factor when you consider the possible cost of re-building a failed engine or gearbox. About £14-£15 per sample.

When you first build an engine, you would note how many miles the engine has done from new when the sample is taken or even comment on the slip you send off with the sample. This is where human intervetion is imperrative, the interpreters will take this into account when looking at the results of the tests. Trending is important so a spike in something like iron in the early life of an engine is quite normal, followed by steady rates of wear afterwards. Any sudden increase is what the interpreters do whilst also indicating the possible source of the issue.

I'm afraid there's no cure for the intollerable poor design of the BMW rocker arms though!! I've had to resort to keeping stocks of mine!!

[graham bahr]

Originally Posted by pmoloney

I'm afraid there's no cure for the intollerable poor design of the BMW rocker arms though!! I've had to resort to keeping stocks of mine!!

true, all be it at an expense you can get steel ones for M10, but i dunno about M20, i assume your using genuine BMW ones, certainly with M10 ones its well known that genuine ones are stronger.

back to the oil testing, maybe you can pm more details?

[pmoloney]

On it's way Graham! Online ordering has just gone live but I don't think I am allowed to post the link...so will play it safe!