Current engine is subaru robin engine eh65 22hp, valves are screwed up and we cannot get the machine ready, gaping them is being a *****, no power to the hydraulics, the machine is ten years old and is need of an overhaul, any engines in the 22 hp or 25 hp that would be compatible with the pt422 system?
did you take the head off and are the valves burned? total hours on machine/engine?
Robins are primo engines, but just pretty rare. I actually have an oem Subaru single cylinder EFI engine powering my Kubota UTV.
two of my favorite places to check out small engines:
Home - Small Engine Warehouse
TulsaEngineWarehouse.com - Replacement Engines, Parts, Tools & Accessories For Briggs & Stratton, Honda, Kawasaki, Kohler & Tecumseh
the questions are usually whether the engine mounts are compatible, the shaft the right size, length and keying, and does the exhaust system clear, among others.
I think you would be better dropping in a replacement engine like David suggested. Considering how valuable your PT is, that cost for the replacement engine seems like a fair investment.
Neither Subaru or Honda builds/markets here small twins over 20-23hp. That market is all Kohler, Briggs and Kawasaki.
Most of us would try to add a hp or two when replacing, if we could, but if you aren't using your machine for full power applications constantly, even dropping a hp or two might work.
funny, I posted the same link as above at the same time...
even funnier is eating my words/hat by studying the link; yes Subaru does market up to 40hp here. that's new.
I checked the dimensions and shaft size; looks like you could go up to 28hp based on similar shafts and similar physical dimensions.
