We recently had a customer send out a gearbox for rebuilding. Up until this point, the appropriate high quality ISO 220 gear oil was being used.
After rebuilding, the gearbox was put back into service with the same, albeit fresh, high quality ISO 220 gear oil that had been used previously. Within a very short period, it was noticed that there was considerable foaming of the fluid.
Our Lubrication Consultant was called in to investigate “what was wrong with the gear oil”.
The Lubrication Consultant took a careful approach to investigating the problem. He asked a lot of questions, leading him to find an interesting situation.
When the rebuilt gearbox was put back into service, the mechanics used a cleaning solution in a spray bottle to “clean” the gearbox of any potential foreign matter. This cleaner is for cleaning ink from printing presses.
An analysis by our technical team quickly found that the ink cleaner was very caustic to lubricants. A Rx was issued to drain the gearbox, refill and flush, then drain the gearbox, refilling with fresh fluid. No more foaming.
Conclusion. Be very careful what you mix with your lubricants. sometimes good intentions give unintended bad consequences.