Reading oil samples

[Canadian_digger]

I have been looking at some used equipment and they give an oil sample for the motor and hydraulics. Thing is I have no idea what the numbers mean. Are there any charts that would tell me what kind of wear is on the components?

[Ross]

Well all the "Finning S.O.S" samples I read come in plain English.

Including a Brief description of any abnormal element count in the oil sampled.

What numbers have they provided?

Ross

[Dozerboy]

Really one sample doesn't tell you much other then the oil was find when they sent the sample in, but who knows if they sent that sample in 2 days after they changed the oil. You need a series of samples to tell anything.

[Canadian_digger]

Ohh ok

Well this is what they give.

date of analysis Dec 19, 2007 Dec 19, 2007
Engine oil Hydraulic
Silicon 7 PPM 5 PPM
Lead 2 PPM 3 PPM
Tin 1 PPM 0 PPM
Copper 4 PPM 6 PPM
Aluminum 1 PPM 2 PPM
Silver 0 PPM 0 PPM
Nickel 0.8 PPM 0.1 PPM
Chromium 1.4 PPM 0.3 PPM
Iron 31 PPM 6 PPM
Glycol NEG N/A
Water NEG NEG
Fuel <5% N/A

[DPete]

PPM means (parts per million) looks pretty clean. You could contact the local dealer about the readings

[bobcat ron]

The first number is the acceptable limits, the next number is how much there is in each of what it's been tested for.

Example:
Chromium 1.4 PPM 0.3 PPM

1.4 is the limit and the 0.3 is what you got, lower numbers aren't always better but then again higher isn't always good either.

[DPete]

The first number is the acceptable limits, the next number is how much there is in each of what it's been tested for.

Example:
Chromium 1.4 PPM 0.3 PPM

1.4 is the limit and the 0.3 is what you got, lower numbers aren't always better but then again higher isn't always good either.
I believe the first number is for the engine sample and the second for the hydraulic system

[Wulf]

Digger... the numbers look good as they are presented but there are so many factors involved in taking and analysing a sample.

Dozerboy summed it up perfectly... oil sampling is OK when used for identifying trends but one sample doesn't really help identify machine condition and value.

BTW... Does it indicate anywhere on the report how many hours are on these oils?

[surfer-joe]

Good numbers mostly for both compartments tho iron is a bit higher than I'd like to see in an engine, but as others mentioned, number of hours on oil and several samples going back a thousand hours or so would be much better indication of present condition.

Trouble is in situations like this, is that the seller often changes all the oils, then pulls a sample and says, "see, all very clean!"

You will have to operate the machinery and let your seat of the pants feel tell you if anything isn't right. Try to get your hands on previous maintenance records or at least talk to someone familiar with the machine.

Good Luck!

[noordzuid dairy]

ya i agree

[noordzuid dairy]

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[noordzuid dairy]

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[Paystar]

I got a book from Toromont Cat that explains all the results. It pretty much explains every detail. They have all kinds of publications you can order.

[AtlasRob]

I have been looking at some used equipment and they give an oil sample for the motor and hydraulics. Thing is I have no idea what the numbers mean. Are there any charts that would tell me what kind of wear is on the components?

The Terex sample kits I use, give machine id, machine hrs, oil hrs, PPM, and highlight anything they consider excessive.
As stated a history is a much better indication of wear, and also maintenance, which is why I do sampling as it is another way of showing I have actually done the maintenance, as on O/op I hope it will give me a better resale value.
I actually shreaded the last lot after my last machine had been sold, but here is the pic I had on my web site during the sale, to show I had the sample results if the buyer wanted to check through them. There are 3 pages laid on top of each other, both rear hubs and rear axle.

[Countryboy]

Welcome to Heavy Equipment Forums noordzuid dairy! :drinkup

[Johnsoils]

Forum Members, I have attached an "Elemental Interpretation Guide" for interpreting oil analysis results. This charts are to be used as a guide only.

As others on this Thread have posted, you really need multiple samples to gage the machines overall condition, as the equipment dealer or individual selling the machine could have changed the fluid(s) recently giving a healthy report. It kinda like the car dealer that always changes all the fluids before putting the car on the lot, you don't know what you got till you drive it while.

It the machine in question had several hundred hours on the the oil samples with results like this, the sample reports results would be reporting a healthy machine and lubricating system.

My advise if you buy the machine is to pull oil samples every 100 to 200 hours and trend the findings. If the wear metal start to jump dramatically and hit the alert levels in a few hundred hours, then the machine might have a system component that will be failing in the near future, and you may have time to trade the machine off or repair it before it fails.

As always oil analysis is worth every dollar you spend on it. Becoming educated on oil analysis and learning how to interpret the results of your samples are worth every minute you spend learning about your analysis program. I can email you the complete Oil Analyzers Inc. users guide to oil analysis services if anyone would like a copy. It is a good place to start learning about oil analysis and interpreting the results.

[Iron Horse]

That's a handy chart , i think the Silicon content is the most telling component in oil . It means you have leaking air intakes or perforated filters etc . If it is high in an engine , chances are the rings and cylinders are now dusted because of the Silicon (sand) entry . If sampled reguarly , the report will tell you too check intake clamps/filters etc and dusting can be avoided .

[joeeye59]

Forum Members, I have attached an "Elemental Interpretation Guide" for interpreting oil analysis results. This charts are to be used as a guide only.

As others on this Thread have posted, you really need multiple samples to gage the machines overall condition, as the equipment dealer or individual selling the machine could have changed the fluid(s) recently giving a healthy report. It kinda like the car dealer that always changes all the fluids before putting the car on the lot, you don't know what you got till you drive it while.

It the machine in question had several hundred hours on the the oil samples with results like this, the sample reports results would be reporting a healthy machine and lubricating system.

My advise if you buy the machine is to pull oil samples every 100 to 200 hours and trend the findings. If the wear metal start to jump dramatically and hit the alert levels in a few hundred hours, then the machine might have a system component that will be failing in the near future, and you may have time to trade the machine off or repair it before it fails.

As always oil analysis is worth every dollar you spend on it. Becoming educated on oil analysis and learning how to interpret the results of your samples are worth every minute you spend learning about your analysis program. I can email you the complete Oil Analyzers Inc. users guide to oil analysis services if anyone would like a copy. It is a good place to start learning about oil analysis and interpreting the results.

Yes please, can you email me a copy of the complete Oil Analyzers Inc.
here is my email, not sure if I can post it here? joeeye@sbcglobal.net

Sorry I don't mean to hijack this post.... but I'd like to ask a question if I can?

Thank you for the great advice in this post, I just got my 1988 JD 310c backhoe, it has 9100 hours.... it runs and sounds very good, it was a well cared for machine. I have the complete maintenance file for the machines repair and service history records from the prior company who owned it since it was new..... so I called them to find out they used Castrol for the hydraulics and for the engine, he did mention it was the conventional Castrol 15w-40 for the engine and not the synthetic. I wish he did use the synthetic for the engine, even tho it sounds and runs good, it does have the normal typical signs that its not a new engine :) ....It would have been nice to have seen this backhoe engine if it had used synthetic oil all it's life to see what shape an engine with 9100 hours on it would run and look like.

I think I'll use both engine oil types, the conventional and a synthetic, and when I change the oil I'll do the oil sample analyzing to see the protection difference.

I put new synthetic fluid in the hydraulics, it did not work out well, when it gets moderately hot I get a squealing howl type noise with the loader hydraulic, and over all it don't sounds nice and tight like the sound it had before I changed it.

[Johnsoils]

joeeye I emailed the oil analysis user guides to you tonight. Thanks for the info request.

[dirthog28]

I'm still a little confused about oil anaylsis. The chart shows for automotive diesels, is there any difference when it comes to equipment. I was looking at a machine with iron of 29ppm in a small cat diesel engine with 1,100hrs is this good or bad for relatively low hours.

[Dozerboy]

That sounds high to me but it may not be to excessive. What does the rest of the sample say?

[dirthog28]

You look at some machines and the iron is low, but then you see some newer machines with 50-90ppm with only like 450hrs???

The rest of the sample for the machine with 1,100hrs showed:
iron: 29ppm
silicon:4ppm
chromium:2.6
The rest was 0 or basically nothing

I can run the snot out a machine, but when it comes to this is like foreign a foreign langage, I don't know if the motor will last another 2,000hrs or peter out 10hrs down the road.

[Johnsoils]

Not knowing all the details on this machine or how many hours were on the oil, I would be comfortable with saying that 29 ppm iron and is not an issue with this machine. The best thing you can do is continue to perform oil analysis and see how the iron and other wear metals trend.

If the rest of the sample looks with all low numbers, and the TBN, soot and oxidation numbers are all good, then I would not drain the oil. I would run it another interval and put another sample.

If you want to email me a copy of the sample, I would be happy to review it for you. You can email it to john@johnsoils.com. If you prefer to mail it, let me know and I can email you my mailing address.

But from what you are telling me hear, continue to run the machine, as I don't see any issues here.

[raju3088]

by what i have read, when a machine starts to have problems it doesnt do any good to get an oil sample unless you have taken samples the whole life of the machine. Am i correct?

[Johnsoils]

Not necessarily, taking an oil analysis will help you pin-point a problem; and also allow you to verify whether or not the problem was resolved during the last repair like a coolant leak for instance. Oil samples are a valuable tool any time you want to see what's going on inside a piece of equipment.

In the referenced question here we were discussing buying a used piece of equipment, and trusting the sellers oil sample report based on only one sample report, and not knowing how many hours were on the oil sample.

At my day job we have large stationary engines that have been in service since 1960, and have over 230,000-hours on them. We perform oil analysis every 1,000-hours on these large stationary 2-cycle natural gas engines. These engines run at 250 RPM and are rated at 2,000-hp. They have an 18" bore and a 20" stroke. The pistons weigh on average 460 pounds.

The oil sample results have played an important part of keeping these engine running all of these years. Some times parts fail and we get a sample that is high in chrome or iron. We know what internal components are sources of chrome and iron and begin investigating the source of the problem. With out oil analysis costly failures would be common, and could cause damage beyond repair.

[dirthog28]

We discussed a while back about engine oil samples, but now what about hydralic oil samples. I've seen a machine with all low, good numbers for the engine oil (so possibly recently changed oil or fluids) but the hydralic oil shows copper being 40ppm and iron at 78ppm. Should a person run from this machine, sounds like high iron number to me, but who knows if they just changed engine oil and not hydralic, so regardless of just changed hydralic oil or not is this mean pumps going out or not?

[Johnsoils]

Dirthog28,

Greetings, it's hard to say as you have indicated not knowing if the hydraulic oil has been changed or not. One thing you could look at is the drain plug or tank access lid. See if you can see that the drain plug was removed or if the tank has been accessed. Also, look for signs of maintenance or repairs on the hydraulic system which might indicate a previous failure. Is the machine on a used equipment lot, or a private seller? A private seller might be straight up if he was the owner about the past history or maintenance.

As far as the numbers 40ppm copper and 78 ppm iron, they don't scare me off if this oil has had some run time. What was the TAN and oxidation numbers? This might help us establish if the oil is relatively new oil, or has seen some hours.

Thanks,

John

[DRESSTA1]

Johnsoils love the chart from the first page. Please correct me if I'm wrong. An oil sample is only as good as the person taking it. If you pull a machine into the shop and let it set overnight because we do not want to service it while it's hot and the next morning walk in and start pulling drain plugs and collecting samples you are wasting your time and money.
An oil sample needs to be taken at operating temperature and with the aid of a CLEAN pump and collecting bottle. I can not tell you how many times I have walked into shops and seen this done.
Also if I had concerns about my hydraulic system I would run a specific particle count test for the hydraulics. It is different than the standard oil analysis. Most major manufatures of equipment today have expanded the service intervals to 4-5000 hours. If it were my machine I would perfrom a particle count every 1000 hours.
I know I am long winded. If you have a machine and the sample comes back dirty. I don't mean if you 've had a catostrophic failure. The first thing people do is dump their oil and fill with new. If you were to sample your new bucket of oil it would probably fail an analysis. Most manufatures offer clean out filters that you run for 8 hours and then put the original back on. Put a set of clean out filters on run it the specified time and resample, it will probably clean up the system.

[Johnsoils]

DRESSTA1,

You are correct! Poor sample practices are going to waste both your time and money. You are also correct when you say that an oil sample needs to be taken at operating temperature immediately after shutdown of the equipment.

A tap valve that is capped to maintain a clean exit port is the best sample method and can collect a flowing sample while the engine/system is running.

A vacuum pump that the sample bottles screw onto is another good method (I use this method a lot on customer vehicles that are not set up for routine oil sampling with a tap valve). It provides good results, and I always pull a bottle of oil through the new sample tubing into an old bottle (that I store on my pump to keep the pump and bottle clean) then dispose of it before screwing on the new bottle and pulling the sample. This will purge any contaminates that may have entered the sample tube during it's insertion down the dipstick tube.

The least effect sample method is as you described "out the drain plug". For some folks this is the only way they have to take a sample and if done properly it will yield fair results, and can tell you if you have a problem. The key is the oil must be hot and drained immediately after shutdown. Then pull the drain plug and let the oil flow out for a while to flush out any sludge or debris from around the drain hole. Then catch a flowing sample.

You are also correct in your statement that most of the time the oil you are draining from your machine will have a lower particle count than the new oil in your bucket/drum. On most hydraulic systems where is the hydraulic filter located? On most machines it is on the return line, and the suction line utilizes a strainer. So new oil travels through your machine before ever seeing a filter if you don't pre-filter it when you are installing it. Several oil suppliers have found particles as large as 150-microns in their clean oil samples. Some companies are better than others, and a drum that has been open for some length of time around the shop will most likely be dirty and have moisture in it. If you are going to have drums around the shop (we all do), I recommend getting a desiccant filter like the ones made by Donaldson or others and place them on your drums so that they are breathing clean dry air. Once the drum's seal is broken it will breath when heated and cooled.

You mentioned clean out filters; an other option is to use a filter-cart to pre-filter the new oil as you are pumping it into the system. These can be expensive for a small operator, but when you consider the cost of repairs to a hydraulic system, it is a small investment that will be around for years if taken care of.

Now you thought you were long winded!!!! Thanks for the great discussion and excellent points you brought to the forum.

[dirthog28]

John I'm not sure what you mean by TAN and oxidation numbers, this is foregien to me. The rest of the hydraulic samples are the following:

Silcon - 6PPM
Lead - 1PPM
Tin - 0PPM
Copper - 40PPM
Alum - 13PPM
Silver - 0.2PPM
Nickel - 0.8PPM
Chromium - 0.8PPM
Iron - 78PPM

[Johnsoils]

Dirthog28,

Oxidation (evidence of lubrication breakdown). The causes of oxidation are: overheating, over-extended oil drain intervals, improper oil type, combustion by-products, blow-by and coolant leaks. A lower oxidation number is good, a higher number is indicating that the oil is breaking down. Conventional oils are typically flagged excessive or condemned at 30 and synthetics lubricants at 50.

Oxidation occurs when lubricating oil undergoes a chemical change under the influence of high operating temperatures or while operating over extended drain service intervals. This can create acids which cause corrosion, increase viscosity and deplete additives. The process is accelerated by heat, metal catalysts and the presence of water, acids or solid contaminants. Oxidation can also cause filter plugging, lacquer build up, sludge deposits, overheating and increased wear. Oxidation is measured by an FTIR scan. The effects of a high oxidation number are: Shortened equipment life, lacquer deposits, oil filter plugging, increased oil viscosity, corrosion of metal parts, increased operating expenses, increased wear and shortened equipment life.

Nitration occurs during the fuel combustion process when combustion by-products mix with the engine oil. This occurs during normal engine operation but is also a result of abnormal blow-by. The products of nitration are highly acidic. Their effects include accelerated oxidation, oil thickening, corrosion, increased wear and poor engine performance. Nitration is measured by infrared analysis or FTIR. Other indicators that may suggest abnormal nitration
levels are a rapid reduction in the oil’s reserve alkalinity (Total Base Number). The effects of a high nitration number are: Accelerated oxidation, increased exhaust emissions, acidic by-products formed, increased cylinder and valve train wear, oil thickening, combustion are deposits and increased TAN.

Total Base Number (TBN) depending upon the application, different oils have different blends of additives designed to maintain the oil’s lubricating properties and protect equipment. Base (alkaline) additives are present in automotive engine oils to neutralize acidic by-products of combustion. New oils start out with the strongest TBN they can possess, depending upon the base oil and the additive chemistry used to make them. Over its service life, a motor oil will lose its ability to neutralize acids. Measuring the TBN strength of the oil is very important when extending oil drain intervals, as the TBN value indicates the capability of the additives to protect the engine from acidic corrosion. The standard test for measuring an engine oil’s acid neutralizing strength, or Total Base Number, is the ASTM-D 4739 Reserve Alkalinity Test. TBN is expressed using a value number, which decreases as nitration and oxidation values rise over the service life of the oil. Because an oil’s characteristics are interdependent, TBN depletion reflects other characteristics of the engine oil that are out of acceptable range. This may indicate that the oil’s service life has ended and the oil should be changed. The effects of a low TBN number are: Increased TAN, oil degradation, increased wear, corrosion of metal parts.

Total Acid Number (TAN) Is the lubricants acid content. Causes of a high TAN number are: High sulfer fuel, overheating, excessive blow-by, over-extended oil drains, improper oil type. The effects of a high TAN number are: corrosion of metallic components, increased oxidation, oil degradation, oil thickening and additive depletion.

If you want more information or a copy of the Oil Analysers INC. User's Guide to Oil Analysis Services, send me a private message with your email and I'll send you a copy. I promise, no spam or junk email.

[Iron Horse]

Johnsoils , I got into a heated debate on another forum when i said a special oil was needed in a vehicle running Liquid Petrolium Gas as a fuel . I told them that i had seen the Babbit metal stripped from the crank bearings because of the acidic by-products of the LPG in the oil . They all said i was wrong . What is your response to this ?

[DRESSTA1]

I was told that LPG was very clean. I will be curious to hear Johnsoils reply.

[Johnsoils]

Iron Horse,

Thanks for the question. You are correct in stating that propane and natural gas engine should have different oil formulation than gasoline or diesel fueled engines. Propane and natural gas engines require a low-ash oil formulation, and typically run cleaner than their wet fueled cousins. As for the acid issue, any time you have combustion gases getting by the piston rings you have the potential to form acids inside the engine. One of the key functions of the engine oil is to combat this acid formation. The TBN (total base number) and additive package all work together to keep the acids inside your engine at bay. Some oils start out with a higher TBN number. Typically full synthetics and several conventional diesel engine oils start out with a TBN of 10 or more. Some synthetics have TBN numbers of 13+. The higher the beginning TBN number, the longer the oil can be ran and combat the acid formation.

I work on large stationary natural gas engine both reciprocating and turbine by day. They range in horsepower from 1,000 to 15,000 hp. The recip engine run a low-ash oil formulated for 2-cycle natural gas engines, and a different low-ash formulation for the 4-stroke natural gas engines. The turbines run a synthetic turbine oil. We perform oil analysis every 1,000-hours of operation. On the turbines we look at the TAN (Total Acid Number) to see if the oil is providing us protection. We have turbine oil systems with over 75,000-hours without an oil change. These systems have an annual make-up of 55-gallons; and a system capacity of over 1,000-gallons of oil. The 2-cycle recip units are 400-gallon systems and use about 15-gallon per day for a 2,000-hp unit. These 2-strokes have upper cylinder lube injection, and are an 18-inch bore with a 20" stroke. So far in my 19-years working on these dino gasser, acid hasn't been a problem, but given an unhealthy engine with serious blowby issues, yes acidic oil could be a major problem.

On the engine you seen the babbit stripped from the bearing, had the oil been ran for an extended length of time? Was an oil analysis been performed to see how acidic the oil was? Just questions out of curiosity, as it is interesting to me since I'm a natural gas, turn'em and burn'em guy by day. In any case I would say that if you are running propane or natural gas you should be running a low-ash oil that is formulated for propane and natural gas engines to maximize not only your oil drain intervals, but to maximize the service life of the engine. Thanks, John

[Iron Horse]

The engines that i saw were mainly Taxis that had been converted and were still using normal oil . The oil was changed frequently but the oil pressures were dropping . After dropping the main and big end caps it became apparent the LPG by-products were stripping the White Metal from the bearings . It had'nt been worn off , it was just gone . Only the shiny Copper shell coatings were left . The oil was changed to Penrite HPR Gas and the problem never returned . It is little known and the only info on the web on the fact is on the pay to read sites , which i wont do but here is a page from one that mentions the problem .

If someone has a little time to spare , i would be keen to see some more evidence on the problem .

[Iron Horse]

This paragraph from the Caltex Havoline LPG brochure explains how it happens quite well . Oxidation and Nitration of the oil causes it to become acidic which can cause rapid bearing failure .