Yanmar GK13–GK18 hydraulics, PTO and implements: what can you do with it?

The hydraulics and PTO of the Yanmar GK13, GK14, GK16 and GK18 make this compact series surprisingly versatile: 550 kg lift capacity, a two-speed PTO shaft, and on the U-versions even automatic implement control. In this article, you'll read what the GK series can handle, which implements suit it, and how to use the lift and PTO correctly.

Suitable for the entire series: Yanmar GK13, GK14, GK16 and GK18 (Ecotra), plus the European versions GK160 and GK200(R).

Yanmar GK13–GK18 lift system: 550 kg at the ball ends

The three-point hitch is category 1N with position control: the position of the lift lever determines the implement height exactly, and the maximum lift capacity is 550 kg at the ball ends. You adjust the lowering speed with the hydraulic stop/lowering speed valve ("oil pressure stop / slow return") — closing it fully locks the implement in the highest position, for example for transport or maintenance underneath the machine. Never let a raised implement rest on the hydraulics alone when working underneath it: close the valve AND support the implement.

The lift, transmission and power steering share the same 7 liters of TF-500 oil. A slow lift is therefore rarely a "lift problem": first check the oil level, then the transmission oil filter (OEM 198421-24910) and the position of the lowering speed valve.

Yanmar GK13–GK18 back-up lift and UFO: the automatic systems

All GK models can lift automatically when reversing (back-up lift): put the main gear lever into reverse and the implement rises automatically — ideal when tilling at headlands. If you don't want this (for example when working with a tipper), you switch off the function with the back-up switch. The U-versions additionally have Yanmar's UFO control: a height and tilt automatic that keeps the implement level and at the set depth, operated via the UFO switch, the setting dial and the hand lever. When buying a U-version, test all these functions — the sensors and actuator motors are model-specific.

Yanmar GK13–GK18 PTO: two speeds plus reverse

The shaft is a standard type 1 (35 mm, 6 spline), so common European implements fit directly. Use position 1 for 540-rpm implements — according to the European brochure the PTO runs at exactly 540 rpm at 2339 engine rpm, so backing off slightly from full throttle is enough. Position 2 is for light work requiring high speed; the reverse PTO is used with a tiller that needs to rotate in the opposite direction, or to free a clogged tiller housing. Always engage the PTO at low engine speed.

Yanmar GK13–GK18 implements: what can it pull and drive?

With 13 to 18.5 hp and a weight of 545–590 kg, this is a light compact tractor: the PTO power is more than sufficient for a rotary tiller of 1.0–1.4 m (Yanmar supplied RZ/RCZ tillers from the factory with working widths from 900 to 1400 mm, matched per model), a flail mower up to about 1.2 m, a rotary mower, a snow blower, or a wood chipper in the light class. Towing work (tipper, cultivator, ridger) works fine as long as you respect the weight: the tractor itself weighs under 600 kg, so front ballast is not a luxury when using heavy attachments. Yanmar supplies a front weight set for this purpose: a base weight of 20 kg (OEM 7TS100-05000) plus up to two additional weights of 15 kg each (OEM 7TS100-04000). Rule of thumb from the manual: with a raised implement, the front wheel pressure must remain sufficient for steering — if you notice light steering, ballast is required.

Yanmar GK13–GK18 track width and stability

The rear track width is adjustable in three steps (for example 800/850/900 mm on the GK16/GK18 standard) by repositioning the wheels; the manual gives torque specifications for the wheel bolts — retighten them after the first 50 hours and every 100 hours thereafter. On slopes and with mowing decks, choose the widest setting your situation allows.