Hello im working on a 349e s/n tfg00712. Have a sample that was flagged for high chromium. the ppm is 7 and was 4 about 300 hours ago. Found about 50 or so small particles of what appears to be brass in the return filter on the bottom of the case but could not find anything in the filter media. Not showing anything in the sample to indicate the brass. Had a second sample taken and shows the same. running speed tests now to see if it shows anything. Would case drain flow be a good test? depends who i ask as to that being a valid test. Thanks for any info Jason
A couple suggestions. I would look close at the cylinder rods. Are they chrome or nitrite coated ? secondly, I wound call the tribologist or the Lab Manager at the Cat dealer that ran your sample and ask him if that is abnormal for that machine. How many total hours on the machine? What’s the ISO 4406? Cat usually doesn’t flag Chromium until 10 ppm. If I recall correctly.
Make sure to sample again in 50 hours. Really need more samples than just two for accurate trending.
Total machine hours.? Cylinders original.? ISO Cleanliness Code is important. What recommendations were included with the SOS reports for the two samples you’ve had analyzed so far.? I’m assuming here that they were analyzed by the dealer and not by an outside lab. Do you have any analysis results prior to the two you mention and what did they show for chromium or anything else that might have been out of the ordinary for that matter. I will have to look for what chromium number throws a flag in an excavator hydraulic system.
I couldn't find any specific info for a 349E but at 2000 hours a hydraulic system sample on a machine of a similar size "Urgent" can be anything from 4 to 7ppm depending on the particular model.
Sorry i should have included this the other day. Im not for sure how to read the iso numbers. The thing that gets me is that im seeing what i belive to be brass in the case drain filter. Bad thing is we do not know witch filter it came from as one is from the pump and the other is from the drive and swing. Im guessing any brass is bad but its not showing on the sample. Fluid has about 300 hours since the last sample that was good.
Good on you for paying attention. You might be able to take care of the issue before a catastrophic failure occurs. Brass in a case drain filter, eh? Could be coming from the slippers or the valve plate. The Chrome is probably from the pistons. The ISO4406 cleanliness level is dirtier than I like to see. But, still within or close to the Cat guidelines. I would ask your parts guy if clean out filters are available for that machine. Run it 50 hours and check those case drains again. Maybe check your case drain numbers while you are at it. This would be a great opportunity to run the oil through a clean-out cart. The wear you are seeing may stop if the oil was cleaner.
Are any of the cylinders leaking?
It's not difficult. Simply repeat what's on the analysis report....... I have attached a document that explains what the ISO Code is and how to interpret it. Basically the higher the number the more particles there were in the sample. What Part Number of filters are you using.? I can look up to see if cleanout elements are available for them.
CD, what are your thoughts on the change for the worse in ISO between the samples @ 8940 and 9206 operating hours (1329 & 1595 hrs on oil), then without a filter or oil change the oil magically healed itself between 9206 and 9487.?
I’m guessing a failed hydraulic hose or a cylinder replacement. The repair probably included the addition of clean oil.
Yeah. No figures for makeup oil to confirm it. That's a shame. Copper stable @ 3ppm despite finding brass/bronze particles in the (I think) case drain filter housing. Hmmmm....
Sometimes the oil control edges on the slippers can chunk-out vs traditional super-fine wear production. Those chunks are too big to measure during sample analysis. The pump may have experienced a shot of dirt from a repair. I’m guessing it has leaking cylinders ingesting dirt pass the wiper.
Speaking of SOS. Paul Cigala with Exxon/Mobil is hosting a oil analysis class this afternoon. I’m looking forward to it
On type of metal in a short time doesn't say imminent failure to me and the interpreter on the report just says to increase the monitoring. The hours on the sample report are in an area of concern as to the life of the components. I've seen issues at as low as 8,000 and then again good life up to 15,000. How long is the stick, how big are the buckets, does the machine travel a lot and does it have twin swing machineries?
I agree with you John, but that does not take into account the brass/bronze particles in the screen, information that would not have been available to whoever did the SOS report interpretation.
Still not a reason to panic. If something is coming apart to the extent of affecting operation, it will make itself known shortly. The OP might do some studying to identify just where brass might be used and check on future repair options. The only change in the sample in the last 300 or so hours of the samples in the chrome content. Particle content actually got better.
We are using 0937521 on the case drains. 179-9806 is the return filters. thank you for all your help. I think maybe the reason it got better is i added oil after we checked case drains.
Sorry, there no Ultra High Efficiency equivalents to either of those numbers. 179-9806 is already a High Efficiency element.
Thanks for the update. I guess, run it and pull a sample in 50 hours. You could measure case drain to get a base line on pump health. Especially, with the brass concern.
Also had a bad sample on a swing drive on same machine. They told me to resample after 2 samples that are 3 times higher on iron. Hear is what i found.
Not sure the reason to sample if they just keep telling me to resample at half the interval.
The metal-eating chipmunks strike again…..