Blog category
Yanmar Forte AF-15 AF-16 AF-17 AF-18
Knowledge base for the Yanmar Forte series: the AF-15, AF-16, AF-17 and AF-18 (1992–1996). These compact 4WD diesel tractors share one family line, but differ in their engines: the AF-15 and AF-16 have the 3-cylinder Yanmar 3TNA72 (879 cc, 72 mm bore), while the AF-17 and AF-18 feature the larger 3TNE74 (1006 cc, 74 mm bore). As a result, the cylinder head gaskets, among other parts, are not interchangeable between the two groups. Here you’ll find purchasing advice, technical specifications, maintenance schedules, oil and filter information, operation, hydraulics/PTO, troubleshooting and storage per topic — plus matching parts from Shop4trac. Please note: the later Forte AF150–AF180 (without the hyphen) is a different series.
06/07/2026
Considering buying a Yanmar Forte AF-15, AF-16, AF-17 or AF-18? Read about the differences between the models, the strengths and weaknesses, and what to look out for when viewing one.
06/07/2026
All technical specifications of the Yanmar Forte AF-15, AF-16, AF-17 and AF-18 from the original manual: engine, dimensions, transmission, PTO, lift, electrical system and tires.
06/07/2026
The complete maintenance schedule for the Yanmar AF-15 through AF-18 from the manual: all intervals, the first service after 50 hours, plus the exact adjustment values for the belt, clutch, brake, and steering.
06/07/2026
Which engine oil, transmission oil and coolant does the Yanmar AF-15 to AF-18 use — and how much? All fill quantities, oil types and change procedures from the manual at a glance.
06/07/2026
All filters of the Yanmar AF-15 to AF-18 at a glance: engine oil filter, line filter, fuel filter, and air filter — with the intervals from the manual and the correct procedure for each filter.
06/07/2026
Here's how to operate and start the Yanmar AF-15 to AF-18: all dashboard lights, the complete starting procedure with preheating times, the running-in period and shifting explained.
06/07/2026
What can you do with the 15 to 18 hp of the Yanmar AF series? Everything about the hitch, PTO speeds, the auto-rotary tilling depth control, diff lock, external hydraulics and suitable implements.
06/07/2026
Yanmar AF-15 to AF-18 won't start, smokes, or the lift refuses to work? All faults with cause and solution — from the original fault tables and from owners' real-world experience.
