This machine has been around since the earlyish 2000s I think. It has a sticker on it Tahmor Mowers. The first thing I ever had to do on it was the bump head and searching or asking about Yard Machines just produced blank looks and pages. MTD had more success.
The first bump head lasted about 15 years but i've had 3 in the last half dozen years. The first one I bought from Carlton Mowers (Sydney), now gone, and I took it to show him and he claimed that the engine was an American built Ryobi? the bump heads are definitely Ryobi.
Danny