Oil analysis

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Oct 12, 2007
Here is some good info for folks to use to analize their oil analysis.



--Edited to fix URL. *Signed, The Management--

-- Edited by Woodsong on Wednesday 30th of November 2011 07:40:08 AM
Interesting article. I wonder though how valid an oil analysis is when done on a recreational marine use 100 hr per year diesel engine. I know everyone does one at survey, but some experts in the field discount the importance of oil analysis as the sole criteria for determining the health of an engine.*

I'm no expert, but I would think that a documented well taken care of engine would have more importance at survey than a clean oil anaylsis. Beside don't most diesel engine failures occure due to overheating or overloading?
After an overheating incident earlier this year I was informed by a mechanic that the engine was toast. However, the oil analysis showed it to be fine and after further investigation the engine turned out to be in good shape. The oil analysis was an excellent tool but only part of the diagnostic process.
I agree about being part of the process. The survey analysis showed fuel in my oil and this led to good research. The paper trail showed all new injectors installed three months previously and no oil change done as part of the service so the reading made sense. It turns out the previous owners had work done requiring shutting off the fuel returns and toasted their injectors when they forgot to reopen the valves. It took a week and additional tests to sort out but the data all made sense.

In the mid 90's I was employed by the local Caterpillar Heavy Equipment Dealership as a product support rep. One of my responsibilities was pulling oil samples from their rental fleet (SOS). The dealership felt there was enough value in this to pay to have it done. I also got alerts from the oil lab when a customers sampling showed a wear trend that indicated the a failure was about to happen. "Before Failure Repair" was the idea and scheduled sampling allowed high hour use machinery to continue to operate until an indication of a failure required attention. This could allow a customer to schedule the repair, arrange a rental, etc. That minimized downtime. Final drives, bevel gear cases, hydraulic systems, engines and transmissions were all candidates. I remember a hydraulic component failure (boom cylinder I think)on an excavator that ended up costing in excess of $15,000 years ago because of the metal contamination after the failure. The customer did not use SOS, and it may have saved him. As has been said often, you need several to start setting a trend on wear patterns. I bet good sampling history would be a great selling feature when you got ready to sell your boat.
Folks that worry about damage from a cooling failure might consider


This liquid is used to allow an engines operation at a much higher (more efficient ) temperature.

IT is not water , so will not have steam pockets , with no cooling , which is what usually caused cylinder head failure.

Expensive , but its insurance , unless you get 215+ thermostats and use it to boost the engines thermal efficiency.
I sample and have my oil tested every time it's changed. Next owner will have a complete set of analysis for the genset, transmission and main engine. All good. Just sent the most recent ones off for analysis.
Forkliftt wrote:*I bet good sampling history would be a great selling feature when you got ready to sell your boat.
*Here is what happened on my last boat while it was under contract.* After the sea trial, in which the engine and transmission passed all tests (max RPM, IR Temp measurements, Tach within 50 RPM of actual)**my broker called me a day later and said*the buyer wanted to have a separate engine survey.* At first I was upset.* Not because I thought the engine would fail but it seemed like a delaying tactic. The engine survey was to be done by a local Yanmar Dealer. I called the dealer and asked what his engine survey consisted of.* He explained that the boat would need to be taken out on another sea trial and that he would check the tach for accuracy, use an IR instrument to check the opening of the thermostat, use the IR to check for hot spots on the engine, see if the WOT in gear matched the WOT in neutral, check for oil leaks etc....

I told him that for the most part that was already done on the sea trial survey by a respected surveyor (which he knew).* I also stated that I had the five oil change reports from the local G Poole Cat Dealer and they all showed the oil to be in good condition with out any contaminants.* He said that if that was all true that he saw no need to do an additional survey.* I FAXed the five oil reports, along with the injector rebuilt bill from 150 hours before,*to him, he called the buyer and the boat went away the very next week.

I feel that without the oil reports that we would have had to under go another survey and had more time lost*which means*more time to back out of the deal.* Was it worth the total*$75 the five surveys cost over the five years?**Not to mention the peace of mind that I have during my ownership.*To me every penny.
Here is a quote from an actual engine survey done Nov. 22:

See Attached Results: Note:, the accurate interpretation of the chemical
analysis of crankcase oil and/or transmission oil is generally possible
only when samples have been taken and analyzed periodically. Only in
that way can benchmarks and a usable pattern be established. Without
that history, someone is just guessing as to the real significance of
various oil contaminant levels. It is also important to understand that
oil analysis will not predict a sudden, catastrophic failure-for
example, the fracturing of a connecting rod. The reason is this type of
failure is not usually the result of ongoing wear.
Hi Folks,

I wrote the Technical Paper on oils, oil degradation and oil analysis. * Please let me know if you have any questions.
I would like to reprint that paper in my marina newsletter. Would that be OK?
Keith wrote:
I would like to reprint that paper in my marina newsletter. Would that be OK?
Yes Keith ... that's OK with me. * *Could I get a copy of the newsletter too please?

Thanks !!!
hzjcm8 wrote:Keith wrote:
I would like to reprint that paper in my marina newsletter. Would that be OK?
Yes Keith ... that's OK with me. * *Could I get a copy of the newsletter too please?

Thanks !!!

Get it on Tom! Was pleasure to speak with you this morn.* Glad I*emailed you the link to this thread! - Art
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