We were recently involved in saving a couple of old Caterpillar Research engines from the scrapheap. The following couple of pages shows the engine being collected and some close-up shots of the engine features. These engines are relatively rare in preservation terms as they were not built in large numbers, being used for research by the oil and fuel companies.
We came across a pair in the USA at the Portland engine show in 2003 (Page 5 of the Portland 2003 set of pictures) but apart from that pair we have not seen any others. We hope eventually to have one of this pair operating with a load, albeit probably an electrical load device like a dynamo or alternator.