×

 

OH, SH#T! A Lube Tech's Lessons Learned

Kevin Keith

OH, SH#T! A Lube Tech's Lessons Learned

The term “OH, SH#T” (or OS! as I’ll refer to it from now on) usually means something bad has happened, but this isn’t always true. Sometimes, it can come from something great happening, like finding a new, faster, easier, or more efficient way of performing a lubrication task.

As a Lubrication Specialist for the past 6 years, I have had several of these moments, both good and bad. Sometimes, if you’re lucky, a healthy combination of both will lead to a new learning experience. If you are not continuously learning and growing (sometimes painfully) from new experiences, you risk becoming stagnant.  

Here are a few of my OS! lubrication moments.

First OS! Lesson

Bullseye sight glasses are a wonderful invention that provides a window into the interior of a machine to examine the level of lubricant inside the reservoir. In one case, however, they led to my first OS! moment.

I installed 12mm bullseye sight glasses on about 24 new gearboxes and filled them to the proper gear oil level. Although they’re not very big, 12mm sight glasses still give you an appropriate level, or so I thought.

I saw the oil flow into the sight glass for the first time, so I knew I had the level right. The gearbox was inspected weekly, including visually inspecting the oil level in the sight glass. The glass always had oil, even after nearly five months of taking monthly samples. As a new lubrication tech, I assumed that maybe I had overfilled the gearbox that first time.

After pulling five monthly samples of 5 ounces (four for the sample and a 1-ounce purge amount), I became curious about how I still had the proper oil level in the gearbox and decided to investigate further.

During the investigation, the sight glass was pulled. The gearbox's oil level was about half what it should have been, but the sight glass still showed that it had the same amount of oil even after it was pulled from the gearbox.

OS! (Not Good)

I discovered that due to capillary action, there was no flow back into the gearbox from the 12mm sight glass. The oil level was immediately taken back up to the proper level. After this, I decided to do away with all the 12mm bullseyes and install column sight glasses with headspace returns in the piping underneath my desiccant breather. That gearbox is still running to this day, so I would call that a win.

I installed all the 6-inch column sight glasses using a 12mm to ¼-inch adapter and all stainless-steel fittings. It is a little more expensive to do it this way, but using malleable iron or galvanized fittings can and will throw off the numbers in an oil analysis report.

The oil from the gearbox flowed into the column sight glass, and all the other gearboxes were filled to the correct amount. All these gearboxes are sampled monthly, which is good because of my next learning moment.

Second OS! Lesson

All the machines in my facility have a preventive maintenance (PM) schedule to ensure they are inspected once a week. This inspection covers:

  • Oil level and condition
  • Desiccant breather condition
  • Gearbox and drive motor heat, leaks, and abnormal noise.

Although samples are taken monthly, it’s good practice to perform your regular inspection while you’re standing there. In my case, the oil was clean, clear, and bright in the column sight glass when I took the oil sample with my vacuum sample pump. But when it came out into the sample bottle, the oil was dark red.

OS! (Not Good)

How could this be? The oil in the column sight glass was in just as perfect condition as the day I filled the gearbox. The reason was because that was the same oil from the day I filled it.

Column sight glasses are excellent at giving an exact level of the oil in the gearbox, but there is no recirculation of the oil in and out of the glass. The only circulation is if makeup oil is added to the reservoir, pushing a small amount into the glass. Otherwise, there is no indicator of the condition of the oil inside the actual machinery. In my case, this oil condition finding was bad but, thankfully, not catastrophic.

Because the reservoir was sampled monthly, at most, I could have had contamination in the oil for 29 days. Had the machine been sampled every other month or, even worse, quarterly, there would have been a longer period of unresolved contamination and more serious consequences for the machine’s health.

Third OS! Lesson

The sample was sent to the lab, but I didn’t wait for the results; that day, I performed a complete drain, flush, and fill. I also began contemplating how to push the oil from the sight glass back into the reservoir to get an immediate look at the oil’s condition. Air pressure is the best option, but it must be “clean and dry” air filtered through the desiccant breather.

Using my own money, I purchased an air pump that pulls air in from a hose on one end of the pump and pushes it out through a hose on the other. I cut my headspace return line, attached the inflow side of the closed pump to the breather side, and attached the outflow to the section of the hose on top of the column.

Throughout this process, I had no idea whether this would work. If it didn’t, I would take the air pump home and use it on bike tires or inflatable toys for the grandkids so my money wouldn’t be wasted.

I pulled out the pump’s plunger, filled it with air from my desiccant breather, and pushed it in. All the oil from the glass was pushed back into the gearbox. It worked perfectly!

OS! (Good)

I installed a push-to-connect coupling fitting on both ends of the cut headspace return line to close the loop on my breather. Now, I could perform a visual check on my weekly PM route with an extra 30 seconds and a $7.49 air pump that I got from a local national discount tool store.

Fourth OS! Lesson

In another instance, I received word that a bearing had gone bad. Everyone has had a bearing fail at one point or another in their career; it happens to the best of us. No matter how much time and effort you put into the care and feeding of a bearing, sometimes they go bad, right?

When the maintenance tech told me a particular bearing had gone out, I knew it wasn’t a human error on my part because it was a sealed bearing – meaning it was behind a “guard” that made it part of the machine’s body and nearly impossible to remove.

You would hope no Original Equipment Manufacturer (OEM) would put a serviceable bearing in a difficult-to-reach place, right? Unfortunately, that was my exact situation, and once removed, I found the bearing was completely dry.

OS! (Bad, very bad)

I run a tight ship and pride myself on that fact; how could I have overlooked this? Truth is, it is easy to do, and I just assumed that this bearing was sealed because of the location. I never checked.

After explaining what happened to my supervisors and admitting what I had overlooked for several years, I set to work on fixing the problem. I did not want it to happen again because this bearing was the first of eight like it in our facility and was next up to lock up. 

My solution was grease line extensions. While not perfect for every situation, in a case like this, they were a great option. During the following scheduled downtime, I locked out the equipment and removed the guard. Then, I installed a push-to-connect fitting on the bearings, ran a pre-filled grease line compatible with our current grease selection out to an easy-to-reach area, and installed a grease fitting. A monthly PM was created for greasing these new (to me) bearings, and so far, none have gone out. In fact, I may have extended the life of the other seven bearings at the expense of one.

Conclusion

These are just a few of the many, many things I have learned throughout my career as a practicing Lubrication Specialist. Although some of these lessons were painful to learn and had me thinking, “OH, SH#T!” they were necessary for my growth – ultimately helping me achieve my positive “ah-ha” moments that made me better at my job.

Subscribe to Machinery Lubrication

About the Author
Kevin Keith is an industry professional with more than 35 years of experience in manufacturing. For the past six years, he has held the position of Lubrication Specialist with Blue Buffalo in ...