The database is intended to become a listing of all known extant steam tractors and portable engines built by steam tractor manufacturers, for the purpose of aiding the research of students and restorers, plus the exchange of information about specific makes and models. The database is searchable by nearly any of the fields, or any combination of fields. Some fields lend themselves to pie chart comparisons, and are available in that fashion here. The technical information is gathered by either direct measurement, or by reference to the manufacturer's printed material.

    The main focus is the machines built by North American manufacturers for use in the farming, logging, and construction trades, but we invite the international community to include their engines as well. The list includes both portable and traction engines. The list does not include models, home-built units, or truck frame mounted rebuilds, unless both boiler and engine were from same tractor. Partial units, such as engines and boilers that have been remounted elsewhere are not being included at this time, although I invite you to send me data about them for future use.

    Information fields include make, model, year, serial number, technical data such as bore, stroke, and boiler type, and current information, such as where the engine is stored/shown, ownership, and so on. Thus, one could look for all 40 hp Cases built in 1917, or one could look for all engines located in their state. Or, one could use the charts page to look at the percentages of wet bottom vs. dry bottom boilers, and so on. is concerned for the privacy of the owners, and will not publish the names or locations of owners unless specifically authorized to do so by that person or organization. Contact information, such as telephone numbers or email addresses, is also hidden unless authorized for inclusion. We will make our best attempt at keeping accurate records of authorization, but if you are an engine owner, and you see information displayed that you would prefer not be shown, contact us here. will NEVER sell its mailing list to third parties for any purpose. A blind email system is in place for users to ask questions of owners, with questions being routed through "".

    We would like to invite all visitors to add as many engines to the list as possible, for it is only with the help of the steam fraternity at large that we will ever approach our goal of including every extant engine. A printable form to help you collect information on an unlisted engine is available here, and the data can be entered online here. Please first check the database to see if a particular engine is listed, so that duplicate entries do not need to be sorted through. We encourage viewers to submit forms for all the engines they know of, but please do be polite when you're collecting the information. The completeness of this list is not worth offending an owner, or getting arrested for trespassing. Please make our privacy policy known to the owner, if asked.

    Minimum information for an entry to be included would be Make, Horsepower, Engine Location (city/state), and either the serial number or the owner's name. This is enough that we can prevent duplicate or false entries - the rest of the information is good to have, but less important.

    If you find an engine in the database that you are personally familiar with, and you think that some of the listed information is inaccurate or incomplete, please contact us here. We check each submission against known serial number lists and manufacturer's specifications, but there is always the chance that the printed lists are incomplete or in error. We do ask that you provide some sort of direct proof in those cases. Incomplete information for an engine means the original data collection was incomplete, or that the engine is one for which we have not yet found literature on. Items like bore, stroke, original operating pressure, etc., were not always listed in the literature, and can be hard to determine without major disassembly. We would rather a field be left blank than be filled incorrectly.