We will likely have the D6C back together & ready to test out by tomorrow (from the steering clutch job) & we plan to put new oils in the trans/bevel gear/ torque & finals. The finals still have the old fluid in them & we plan to drain them once the machine is up running again tomorrow & replace with new oil. Should the machine be warm & used actively for a while before pulling samples or is that not important? Would seem to us that by moving or working it, any potential foreign particles may have a greater chance of being suspended in the oil & more detectable when sampling?
Absolutely yes it should.
I would also suggest that if you have any doubt whatsoever regarding how much contamination you might have in any/all of the compartments that you have rebuilt, getting the compartment in question up to temperature and then dumping a load of 10W hydraulic oil in it is a good way of flushing out. All you need to do is exercise the machine carefully for say 30 minutes without putting too much load on it, then drain the hyd oil and refill with whatever is the correct oil for the compartment. I would do all that before even thinking about taking samples. Also when you have the samples analyzed make sure that the laboratory you use gives you a) an interpretation of the results (some don't) and b) an ISO Cleanliness Code Number. Post the numbers here if you need any help in interpreting them.
Ok, thanks for the information. Given the fact that this is an old machine that we do not intend to put a lot of hours on, would you recommend going to the expense of flushing it with #10 & then dumping it before filling with the correct spec if it were yours? I can post the specs of the samples when we do them, as we will not likely know how to read them. The sampling I was mentioning earlier was the finals (still old oil in them) before we change them out, not the rebuild area at this time. Maybe it is not a good idea to sample the old oil in the finals at this time, as they were overfilling from the clutch compartments & likely much of the oil was from there & if there is contamination it may have migrated from elsewhere? Thanks, Metalman
Ah, that puts a slightly different slant on things. When you say you are not going to use the machine a lot, roughly how much use are we talking about? There's not really much point in sampling oil which has done under about 50 hours, and if it's going to take you say 6 months to put 50 hours on the machine then the samples probably wouldn't be representative anyway due to condensation and surface rust forming while the machine is parked. Oil sampling is essentially a tool used to establish trends. A one-off snapshot of the oil in a compartment is of limited use in establishing whether something untoward is happening. If you're still keen on sampling, I would suggest sampling the F/Ds to establish a base line before you drain/flush/refill. If you make a note in the machine's service records that the sample was taken pre-repair and may be cross contaminated, you can take this into account when interpreting the results. The real insight will come later when you compare the next sample to the first, and it will also be equally informative when you compare left to right. On the other hand, if you want to save the money, you could just flush the finals and check the magnetic plugs regularly.
I had a major problem with the sampling that they did on things like belt speed reducers and shaker screens where I worked. Instead of sampling maybe two or three times during the operating season most of the time they got the urge to pull samples a week or two before start up in the spring! Like that really told them anything and even if some came back with indications of major problem, well "We can't tear it apart now, big boss says we have to be running the first of the month!" On the mobile equipment I serviced I at least pulled engine samples at every oil change and other compartments were sampled at half service intervals for that compartment. Almost without fail the first engine oil sample of the season would show a bit of a spike for high iron that I always related to the cylinders getting a slight bit of rust on them sitting all winter. Probably would have been an idea to use some fogging oil or some such thing when parking but they always seemed to want to run them till the last day of the season then send everyone including me home till a couple weeks before spring start up. Didn't mean to totally hi-jack the thread, but in a round about way agreeing that a one off sample on more or less new oil on a low hour use machine will not give a lot of information.
If it was mine and it had all been apart, yes I would flush it with 10W. After spending a bunch of hard-earned $ I would want some confirmation that I hadn't been working for nothing. How much will a few gallons of 10W and some oil samples run you compared to what you spent on repairs..? I agee with CM that samples are probably of limited value if the machine isn't going to work a lot of hours. However it might pay to at least one sample of each compartment after the drain/flush/refill process to establish a baseline, especially when it comes to the Cleanliness Code of the oil. That number tells you if your flush actually worked or not. I would drain/flush/refill the finals, run the machine a few hours, and then sample. As you rightly point out the finals will have been contaminated by oil transferring from other compartments.
Only about 75 hrs use in the next 6 months.