18 hp onan twin
those older pre-Ca.1981 onan twins were all iron except the heads-quite heavy,though some have been used to power tiny homebuilt airplanes!apparently they are very adaptible to that purpose.The little ford 1100 i saw is gone from the lineup at the used implement store,but if it doesn't reappear equivilent japanese micro tractors are quite common-many as used units imported by the containerload from japan and sold by used tractor dealers.My lawn tractor is a 1995 MTD "general" with 11hp briggs single-kind of a cheapie,but has done ok so far-engine has sprung a minor oil leak i need to fix...