Rebuilding Cat 3116 Diesel Engine Out Of A Pusher School Bus

Mechanics Hub - September 30, 2013

The Cat 3116...this engine was introduced to our fleet starting in 2007 and the first thing that we had to do was get a hold of the tool kit required to make adjustments. Adjusting the valves is one thing that can be done easily on any diesel engine. But since the 3116 had a governor and fuel rack system there was a learning curve.

The fuel setting, synchronization and injector timing requires the CAT tool kit. Without the proper tools you can not adjust these engines properly. The kit has a gauge block to set up the timing tool fixture. There is a dial indicator tool for injector rack synchronization and fuel setting.

Luckily I was sent for training on these engines and without that hands on experience it would have taken a longer time to grasp the set up and adjustment procedures. The 3116 had a very durable bottom end but the top end had it's problems.

Around 2005 when these engines came out they weren't warming up fast enough and the exhaust valves were seizing in the guides from carbon build up. Cat had an intake heater to assist engine warm up but it would draw so many amps the alternator would get dragged down. They worked around these problems by recalibrating the coolant temperature sensor to activate the grid heater sooner and then cycle the heater on and off.

Since each cylinder had only one intake and one exhaust valve this made them more vulnerable to heat and we had a few engines that dropped the exhaust valve. The video above was one of those engines and as you can see it means a complete rebuild. I liked the 3116 for it's performance and we had 13 of them in our fleet. Regardless of he failures they performed well.

They are no longer available in the truck industry and CAT has gotten out of the highway truck engine department. Leave a comment if you've heard otherwise....I've heard a rumor that they will be working with International on a new truck engine for the IC line. Comments anyone? :)

Diesel Engines