Machining 101: A farmer’s guide to engine machine work

Machining 101: A farmer’s guide to engine machine work

June 26, 2018 0 By Ray Bohacz

I realize that there are many obstacles on the road to a prosperous agricultural operation. The best results are usually obtained when there is a level of understanding that allows for an informed decision or purchase. The educated farmer is the most prudent consumer of the things he buys or the business decisions made.


With internal combustion engines of every size, make, configuration, and fuel type employed on the modern farm, there will come a time when some of them will require a major repair or overhaul.


To this cause, I have prepared a series covering the pertinent topics that must be understood to be an informed buyer of engine machining/repair services. It is not my intent to make you a machinist, but instead provide the knowledge to guarantee that your investment in these services will return the quality and reliability that is required. We have all heard horror stories or experienced them ourselves of expensive engine repairs that were not done correctly and the resultant loss of productivity from that important machine. It is the goal of the Farm Machinery Digest to help you avoid that.


Some may be thinking that this is not a concern for them since most manufacturers offer a factory line of remanufactured engines and components. When offered, that is usually the best approach. There are times when a factory-backed remanufactured engine/part is not available. For example, you may have a grain truck or older tractor that is no longer supported by the manufacturer with rebuilt engines or cylinder heads.


As an aside, the knowledge you will glean in this series can be used to query the engine manufacturer about their services and procedures. This will confirm that it is being done to the highest standard and not just an assumption of that.


The quality of engine machine work is dependent on three things: the equipment employed, the steps taken, and the skill of the operator. A shortcut in any of these areas will impact the performance of the final product or its longevity. It can be thought of in similar fashion to planting a crop — the end result is the seed is in the ground but we all know there is much more to it than that. If not why would so many spend six figures on an advanced planter?


Sadly, many shops that offer machine services for agricultural engines use antiquated and out-of-tolerance equipment and also skip many important steps. For example, they may not resize both ends of the connecting rod, check the line bore on the block, or accurately set the installed height of the valves and spring pressure on a cylinder head. The engine will run but not much more can be said about the investment you made.  Simply put, details make the difference. A properly remanufactured engine should perform like new with no compromises at all.


This series will include three parts with this being the introduction.


Part 1: Engine block
Part 2: Rotating assembly (pistons, crankshaft, connecting rods)
Part 3: Cylinder head


The procedures discussed will be applicable to both gasoline and diesel engines with application specific exceptions. As an example, most but not all agricultural diesels employ cylinder liners while light-duty versions and gas engines usually do not. The information I will supply can be applied to any engine you have on the farm or in your personal inventory.


I am proud to have worked with the staff and students in the agricultural and engine building programs at the University of Northwestern Ohio (UNOH) at their campus in Lima to create this series. The school has the most advanced equipment and a dedicated and knowledgeable staff that is familiar with the needs of the agricultural community. Many of them are actively involved in farming.


The best-case scenario is that you never need to buy engine machine services — but if that day comes we trust this series will allow you to make an informed purchase.