Articles – Page 27 – Mechanics Hub

School Bus Mechanic Garage Talk

Allison Transmission Clutch Pressure Test This is an old photo testing clutch pressures on an Allison 3000 series automatic transmission. The pressures would tell the story on clutch slippage and pressure retention when the transmission was at different shifting points. The tool of the day back then was a “ProLink” which was a hand held… Continue reading School Bus Mechanic Garage Talk

School Bus Emission Warning Lights

The HEST (high exhaust system temperature) warning light and the DPF (diesel particulate filter) or exhaust filter are the two main indicators that tell the operator when a manual regeneration is required. The ECU is programmed to initiate what is called a passive regeneration while the engine is running on the highway or in the… Continue reading School Bus Emission Warning Lights

School Bus Auto Chains

Installing auto tire chains on a school bus takes a better part of a day but it’s so worth it! All the service calls I went on to get buses out of a jam during a winter tire spin out was endless. One time a semi truck and trailer spun out on a hill which… Continue reading School Bus Auto Chains

Life As A GM Mechanic

The New Cummins V8 5 Liter Diesel

The Cummins ISV 5 Liter diesel will be going into the Nissan Titan for 2015. The original plan was to fit these engines into the Dodge Ram but that did not happen. The reason was the engine manufacturer for Fiat VM Motori has a 3.0 Liter diesel that is kicking butt in the fuel mileage… Continue reading The New Cummins V8 5 Liter Diesel

Low Power No Codes Maxxforce DT Diesel Engine

Low Power with No engine codes is a tough problem to have because of the lack of information which generally comes from reading an engine code. A lot of times a code will point you in the right direction and give you a general idea what area of the engine to look at. In this… Continue reading Low Power No Codes Maxxforce DT Diesel Engine

Maxxforce 7 Turbo Waste Gate Repair

“No Power” 2008 International MaxxForce 7 Diesel Engine – No Turbo Boost This is what we discovered on our one and only International hybrid school bus equipped with a MaxxForce 7 diesel engine. The complaint was the ever so common “no power” problem so we hooked up the laptop and the diagnostic software and went… Continue reading Maxxforce 7 Turbo Waste Gate Repair

Working as an Apprentice – the Trials and Tribulations

The end of April, 2011. I was fresh out of my entry level trades training in Vancouver. I had taken a year of diesel engine technology, at the British Columbia Institute of technology. I was very confident, and eager to get the ball rolling on this exciting new career. I had studied hard and gotten… Continue reading Working as an Apprentice – the Trials and Tribulations

Checking Out School Buses For Sale

Allison Automatic Transmission Wiring

An Over View on Allison Automatic Transmission Wiring We didn’t experience the New World Transmissions from Allison until 1995. The ER Saf -T- liner Pusher buses all came equipped with 3000 series transmissions and for the most part they were very reliable. At least until the wiring problems began a year or two later. Owning… Continue reading Allison Automatic Transmission Wiring