Petrol Tiller GTM620-3 18HP 4-Stroke Heavy Duty Engine for Garden Farm Allotment. The Petrol Tiller GTM620-3 features an 18HP 4-stroke heavy-duty engine, making it ideal for intensive tasks in gardens, farms, and allotments. Its high power ensures exceptional soil preparation and cultivation. Designed with adjustable tilling settings and sturdy construction, this tiller offers reliability and …