Caterpillar C7 seized due to paper debris

This case reported by Bartech Marine Engineering which serviced the subject engine.
According to Bartech Marine Engineering, the turbocharger of the Caterpillar C7 engine overhauled about 10 months ago. Trouble was, after 130 running hours, the turbo had seized, and the client wanted it to be repaired under warranty.
The normal cause of seized turbos is a lack of the bearing lubrication- as they could be turning at 20,000 RPM, the shaft needs sufficient lubrication.
Instead, some paper had been allowed to get into the air intake, stuck between the compressor wheel and casing, and this had stopped the turbo turning.

Lessons learned

1. Proper cleanliness is very important during servicing and overhauling of equipment.
2. Turbocharges must not be allowed to run without air filter as even smallest debris sucked inside could lead to a catastrofic failure.