Group 13 - Product Name Here
MAE 277 Group 13
Tecumseh TNT100 Lawn Mower Engine
- Tyler Lynn - Project Manager
- Dylan McCann - Technical Adviser
- Timothy Li - Communication Liaison
- Garrett Lust - Editor
The Tecumseh TNT100 was originally manufactured in the mid 1980's and was used as a lawn mower engine. It is a one cylinder, 4 stroke, "flathead" engine. The TNT100 also has a vertical crankshaft, and a side mounted carburetor that feeds air into the head through one of the two valves. The other valve lets exhaust gasses escape through a simple "canister style" muffler. It is a simple, proven, reliable design.
The first gate consists of the project management and the product archaeology. The project management was a work proposal and management proposal. The work proposal allowed us to provide an overview of how to reverse engineering our engine without taking it apart. We examined the engine to figure out the equipment and process needed to reverse engineer the engine. The management proposal allowed us to assign ourselves to individual roles, which taught us responsibility and time management. The product archeology allowed us to use our past experiences to mentally dissect the engine. We created a flow chart of the engine’s subsystems to familiarize ourselves with the components functions.
The second gate was a step by step process of dissecting our engine. The processes consisted of a brief explanation of how we disassembled the part, a difficulty rating of easy, medium or hard and photographs of the disassembled part. We were inexperienced with wiki and did not know how to create tables. We also had to write about the subsystem connections. We described each function with a short paragraph and a brief video. The project management for gate two allowed our group to assess our flaws and challenges that we will face within our group and how we plan to fix them. The main difficulty of this gate was, not knowing if there are missing pieces from groups that previously disassembled the engine.
Gate three consisted of a product archeology, solid modeling, engineering analysis, and three design revisions. We had to document each of the product’s components with a photo, the component’s function, materials used, manufacturing processes used, label with a part or model number, and relevant information. Our analysis began with a very organized table. The table was divided into five different rows for specifications, component function, component form, manufacturing methods and complexity. The complexity was rated based on the number of component functions, number of manufacturing processes and the overall geometry of the part. We used a number scale that went from two to eight, two being simple to eight being very complex. We analyzed with great detail with our eyes and hands, and with information that we were unable to obtain physically, we researched the individual part. Our group used Autodesk Inventor Professional 2012 for our solid models. We modeled the piston and the connecting rod. For our engineering analysis, we analyzed the heat sink. We showed the rate at which heat dissipates from the heat sink. Our three design revisions were changing the geometry of the components, the material, and adding a second cylinder.
Our fourth gate consisted of the reassembly of the engine and three design revisions at a system level. Our group had a big struggle in this gate; we were unable to complete the reassembly. This allowed our group to figure out the remaining flaws and challenges that we still faced. We planned to correct our mistakes and no repeat it in our final gate. We completed gate four to the best of our abilities. Our design revision consisted of redesigning the engine from the ground up to make it a 2 cylinder engine. We would also want to remove the pull start and replace it with a button start. The last revision would be adding a liquid cooling system.
Our fifth gate consisted of an oral presentation in class and revisions of all the past gates and of the wiki to finalize its presentation. Using the feedback that we received from the grades on gate 1-4 we reassessed our work and completed anything that we did not finish in time. A full description of our revisions can be seen in gate 5 below, but the revisions themselves occurred in the previous gates.