Are you sure, there was a Walter M601 next to it and the chap who talked to me about the new engine was comparing it to the Walter's performance?
The Fletcher ZK-EUC was owned by Robalan Air Ltd of Napier. When Fieldair sold the aircraft to the operators, the 400HP engines were leased. The Fletcher was replaced by an Air Tractor AT-502 (ZK-PTK) which arrived in March 2004 and the Fletcher engine was returned to Feildair shortly after. ZK-EUC was stored at Napier and then sold to Bill Sutherland of Waikaia in November 2006 where it was stored. Bill Sutherland, a director of Phoenix Aviation wanted to explore the installation of diesel engines into a Fletcher. At that time there was only engines available up to 300HP, not enough HP for the Fletcher which required 450 to 550HP.
The diesel engine now fitted to ZK-EUC is a Red A03/V12. It was designed by a Russian Vladmir Raikhlin and first run in 2009. A company had been set up in Germany, Raikhlin Aircraft Engine Developments Gmbh and is now known as RED Aircraft Gmbh. The engine received certification by EASA on 19 December 2014.
So at this stage ZK-EUC has not flown and I can see by your photo, a lot of work still has to be done. And if it works, it will replace the Walter M601D-NZ. As no one has converted a standard Fletcher FU24-950/954 to be powered with a small PT6A, it another option but expensive.