DIRTY STUFF
MOST of us have had at least one mongrel disaster – an expensive engine or transmission blow-up that ripped off a fat wad of the folding to fix. Wouldn’t it be fantastic if we could see inside blocks and stuff to spot a failing component before the damn thing really lets go? Although nobody has developed this technology yet, there are other ways to know that something inside is about to fail and create a truckload of grief.
The most obvious method is to look inside the tin-can oil filter. By carefully cutting the top off, without dumping metal fragments onto the element inside in the process (there are special tools available to do this), you can pull out the foreign-body-trapping element and cut that apart to see if there are any sparkles trapped in the folds. Any steel shavings, aluminium particles, red traces of copper or grindings of cast iron will tell you that the engine has to be stripped. Then you can find out where this contamination has come from before maybe a stuffed conrod bearing ends up making an air hole in the side of your block!
Mining and earthmoving operators buy very expensive, very large machines that work around the clock, powered by equally expensive diesel engines. They do not want disasters to halt production, so they routinely take samples of engine, transmission and hydraulic oils and send these to their mostly in-house testing laboratories. There, they look for signs of nasty stuff that would seriously cripple a machine. They can analyse where the metal came from and rip stuff into pieces to fix up the problem.
I have a mate who manages one of these laboratories; they run a battery of complex tests on these samples and send reports out as to what they find. Many testing labs are also open to checking oils from private individuals, so here is a brief rundown on these steps.
The sputter test. This one is simple. You need a hot plate and a sample of the suspect oil, plus some of the same oil that is yet to do work inside a machine. They drop the suspect oil onto the plate, and if it sputters, they know then that the sample is contaminated by water or coolant. If they drop some new oil on the plate and it doesn’t sputter, that’s positive proof that the techs back at base need to look for a blown head gasket, or maybe a crack or porosity in a casting.
FTIR – Fourier-transform Infrared. They are looking for oxidisation or soot, a sure sign that there is a combustion problem happening inside the engine – possibly a broken ring or the beginning of a side about to melt in a piston. They also check for oil viscosity, with engine oil heated to 100 degrees and transmission
WOULDN’T IT BE FANTASTIC IF WE COULD SEE INSIDE BLOCKS TO SPOT A FAILING COMPONENT BEFORE THE DAMN THING REALLY LETS GO? STILL, THERE ARE OTHER WAYS TO KNOW THAT SOMETHING INSIDE IS ABOUT TO FAIL
final-drive lubricant to 40 degrees.
ICP-MS – Inductively Coupled Plasma-mass Spectrometry. A plasma check, looking at the light intensity when a sample is burning. This will indicate the presence of metal particles, and they can pick up tiny flakes of aluminium down to eight microns.
There are still other test methods involving heating and stirring, looking for damming evidence that will advise the techs of a pending machine breakdown.
These enormous and costly earthmoving and mineral-hauling machines can be unexpectedly shut down by a simple servicing error. My mate tells me that at one mine site, a giant spoil mover was disabled through a major piston and ring problem. They had a huge investigation by reps from the manufacturer of the engine, because the shutdown and repair involved a cubic bin of money, and they finally worked out that one simple O-ring had caused this disaster. The servicing tech had routinely changed the air filters and got the refitting of the intake trunking wrong, misplacing a vital sealing O-ring. This allowed much dust to get into the engine, destroying rings and stuffing cylinder bores.
I have another mate who is a marine engineer responsible for the continuing health of giant ship engines. His job, among others, is to advise the company as to which type and grade of oil should fill the sumps, which hold huge quantities of oil. His advice, driven by thorough practical and theoretical research, was overruled by the company accountant, who said your oil is way too dear; you will use this cheap-and-nasty oil that will save us lots of dollars. Despite his objections, he had to accede, and then the mammoth ship engines blew up, one after another!