Oil Analysis

[W5FL]

The Kubota dealer gave me 2 oil analysis kits to fill and send it. I guess one is for the drained engine oil and the other is for the drained hydraulic fluid. Will this analysis yield whether it is UDT or Super UDT? Will the oil tell whether it is 15W40 or a single weight oil? Any idea how much it cost to continue this service?

 

[MChalkley]

Wen - Usually the labs want you to tell them what kind and weight of oil it is. I don't know if they can tell exactly or not, but they can tell you how much of it is synthetic. Primarily, they just look for contaminants. They want to know viscosity because they can then determine how much it's varied from the baseline. It also depends on the lab, too. I'd just tell them what you know and see what they say. They usually charge between $10 and $15.

Mark

 

[W5FL]

What is the best procedure for taking samples of oil and samples of hydraulic fluid. I would assume that you would drain at operating temperature and after being in use so any particles will be in suspension and take the sample about 1/2 way through the draining process. Any suggestions appreciated. I have one container (looks like about 4 oz) for the engine oil and one container for the hydraulic fluid.

 

[MChalkley]

Wen - According to all I've heard and read, what you described is the ultimate approach. I have a tap on my bypass filter that I use to fill the sampling bottle. With the engine running, I run an ounce or two out to clear it, then fill the bottle.

Mark

 

[W5FL]

Well, I took the samples and sent them off to DARR yesterday. The guy at the USPS wanted to know what was in the bottles before he would mail them although they had postage pre paid stamped on them.

The hydraulic fluid was red in the front differential and brown in the front gear axles and rear differential/transmission.

All fluids appeared to be pretty light in visciosity, but it was 95 degrees, too. Is there an easy way to measure visciosity except by comparison with another fluid?

Is UDT characteristically a brown color?

The Super UDT had a light yellow cast (guess that was the flakes of gold floating around in it).

 

[Mike H]

I don't think there's any easy way to measure viscosity other than by accessing a viscometer. I've seen a formula for calculating viscosity based on measuring the length of time it takes the fluid to move down a slope, but for this you need to accurately measure the slope angle, know the fluid density, measure the thickness of the sliding film, etc. There's also a viscosity unit of measure call an SSU (Saybolt Second Universal) that came about by measuring the time it takes for a fixed volume of fluid to pass through a particular sized orifice. This one might actually be doable - there's an ASTM spec. on it but I've never looked at it. There are equations to convert SSU to cP or other more recognizable units. But you did say easy, didn't you! I'd have to vote for pour a couple of fluids on a ramp and watch them (or find a relative who works for a lab)

 

[Anonymous Poster]

Some time ago-a site was posted that had a rather complete discussion concerning various brands of oil filters. Does anyone have this info??--Thanks

 

[Anonymous Poster]

I think the site you are looking for is:

http://members.xoom.com/minimopar/oilfilterstudy.html

In my opinion this site is not very usefull. While the filters are cut apart and compared, the filtration ability and how long this ability lasts is ignored. The only reason for a filter is to filter the oil the rest of the construction is secondary.

Andy

 

[W5FL]

Re: 50 hr Engine Oil Analysis by Darr

The M6800 Engine Oil 50 hour Sample analysis came back as Normal wear on a first sample basis.

Viscosity 10.4
Copper 5 ppm
Iron 9 ppm
Lead 2 ppm
Aluminum 2 ppm
Silicon 18 ppm
Sodium 5 ppm
Magnesium 16 ppm
Tin 5 ppm
Zinc 929 ppm
Phosphorus 868 ppm
Calcium 3700 ppm

No Water, Fuel, or Anti Freeze
Chrome, Molybdenum, Potassium were all 0 ppm

This is the original oil that came in the Tractor from Kubota. Guess the only thing I can tell for sure is that the break in oil was probably 10 weight, but if anyone can speculate any more than that, please post for everyone to see. I have no idea whether the metals came from the tractor or came in the oil originally since I did not obviously have an unused sample. Maybe someone else will take a sample at zero hours and we can then compare.

The analysis was done by DARR Equipment Co 1-800-733-3277 They sell the vials for between $10 and $15 each for the analysis.

 

[Mike H]

Re: 50 hr Engine Oil Analysis by Darr

Wen: what were the units for the viscosity measurement?

 

[W5FL]

Re: 50 hr Engine Oil Analysis by Darr

Viscosity is reported in centistokes which represents oil flow time through a calibrated glass capillary tube at a standard temperature.

Glad you asked. Now is that the same as 10 Weight?

 

[W5FL]

Re: 50 hour Hydraulic Oil Analysis by Darr

The M6800 Hydraulic Oil 50 hour Sample analysis came back as Normal wear on a first sample basis.

Viscosity Not Tested
Copper 2 ppm
Iron 8 ppm
Lead 1 ppm
Aluminum 2 ppm
Silicon 6 ppm
Molybdenum 1 ppm
Sodium 27 ppm
Magnesium 16 ppm
Tin 1 ppm
Zinc 1130 ppm
Phosphorus 1070 ppm
Calcium 3500 ppm

No Water
Chrome,Potassium were all 0 ppm

They also tested particle size which I would assume is primarily from the disk brakes (driving with the emergency brake on) and from the pto clutch which is also in the hydraulic fluid on this tractor.

Large Particle Size
> 5 9,135 ppm
>10 1,408 ppm
>15 96 ppm
>20 31 ppm
>25 14 ppm
>50 2 ppm
>75 0 ppm
>100 0 ppm
ISO CODE 20/14 (whatever that means)

This is the original hydraulic fluid from the transmission/rear end that came in the Tractor from Kubota. If anyone can speculate any more than that, please post for everyone to see. I have no idea whether the metals came from the tractor or came in the oil originally since I did not obviously have an unused sample. Maybe someone else will take a sample at zero hours and we can then compare. The oil in the front differential was different and was a red color where this oil was a brown color.

The analysis was done by DARR Equipment Co 1-800-733-3277 They sell the vials for between $10 and $15 each for the analysis.

 

[Anonymous Poster]

Thanks Andy-I agree with your wisdom. Bought a new Super Duty (V10) and am putting together my maintenance program. Being an engineer, I spend way too much time thinking about these types of things.

 

[Anonymous Poster]

Re: 50 hour Hydraulic Oil Analysis by Darr

Wen, Thanks for the post on your oil analysis. Since I'm not a metallurgist/chemist nor engineer (When it comes to making a glass of chocolate milk, I still have problems getting the powdered milk chocolate to marry up with the milk) does anyone in the group know what the acceptable ranges/limits are for all the elements listed in an oil analysis??

 

[Mike H]

Re: 50 hr Engine Oil Analysis by Darr

Here's some 'rough' guidelines. I'm reading this off a logarithmic scale so this isn't as exact as it looks:

For crankcase oils
SAE 10W is approximately ISO 32 and is 30-40 cS at 40C, 5-6 cS at 210F
SAE 20W is approximately ISO 46,68 40-80 cS at 40C, 6-10 cS at 210F
SAE 30W ISO 100 80-120 cS at 40C, 10-15 cS at 210F

 

[W5FL]

Re: 50 hr Engine Oil Analysis by Darr

Can you translate that against the reading for engine oil or hydraulic fluid? Sounds like less than 10W for engine oil and not sure what the iso number meant for hydraulic fluid.

 

[Mike H]

Re: 50 hr Engine Oil Analysis by Darr

Oops, I reread my post and I think by putting in both SAE and ISO info. together (English and metric!) I was being obtuse! The data was for "crankcase" oil which I'm certain is your "engine" oil. I've also got SAE gear oil info. but for some reason my chart didn't have hydraulic oils. I'll look again when I go back into work next week. For reasons that are beyond me, 40C appears to be a standard test temp. for ISO and 210F for SAE. I bet your sample at 10.4 is tested to the American spec's so I'm guessing it's a 30W (the number is on the high 20W, low 30W scale). Perhaps even more likely it's a multi weight 10W30 like what was theoretically originally in my boomer! If they ship it with a multiweight, they don't have to worry about whether it ends up in TX or MI!

 

[W5FL]

Re: 50 hr Engine Oil Analysis by Darr

I can see the 40 deg C as that is probably a decent summertime temperature. But it looks more like 5W rather than 30W. Yes, I thought it would definately be a multiweight oil or a very light break in oil. See if you have 40 degree at 10 CS that will translate to a 5W or so number.

Where are all our heavy equipment operators when we need them?

 

[Mike H]

Re: 50 hr Engine Oil Analysis by Darr

Yes, 40C, 10 cS looks like it's 5W. It's kind of funny - the bottom of the 5W range on my chart is covered up by a note so I can't say what the range really is!

 

[craigb]

Re: 50 hr Engine Oil Analysis by Darr

I will try to explain how we utilize oil analysis in naval aviation. Most jet engines are on routine oil analysis, every 10 hrs, 20 , 30 hrs, etc, depending on the age and past history. All engines produce various wear metals (depending on wear surface and bearing designs) and there will always be various amounts in each sample. New engines require an average of three samples in the first several hours to establish their baseline averages. These baseline averages are compared to established tables to see how they fall out. Once we go to the hourly cycles we look for jumps in wear metals that possibly show an increase in wear. The first sample really gives no help but to establish baseline figures. Do not be worried by the fact that you have metals in suspension as this is normal. IMHO unless the oil lab or the dealer can provide you with established metal limits you are not gaining any knowledge unless you routinely provide samples and look for large increases. Just for info military jets use synthetic oils and most never change it until the engine is pulled for major inspections (average 800 flight hours). Sorry to take so long but I used to run oil sample machines and am sold on the idea for aviation.