Lets look at the tach on the YM2310 for some clues.
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Its the tach with no help for PTO use.
On other YM machines like the YM3110, the tach is robust with various levels of running 500 to 540 PTO rpms at various engine speeds and the multi-speed select PTO selected from 1, 2, 3, & 4.
View attachment 757168
Notice the PTO indicator with (1) (2) (3) (4). Then follow around till you find the 500rpm mark for each radius.
View attachment 757176
PTO (1) 500rpm charts to be 2200 engine rpm
PTO (2) 500rpm charts to be 1900 engine rpm
PTO (3) 500rpm charts to be 1300 engine rpm
PTO (4) 500rpm charts to be 1100 engine rpm
So, with the speed of the engine RPMs, the PTO speed can vary.
You are now asking, how can you chart this on a YM2310? Not easily via the tach.
Instead you need a Tachometer photo sensor hand held device. Using a dab of paint on one of the PTO spline teeth, paint it white. Next, with someone in the seat, operate the tractor in each PTO setting while adjust the engine speed to find either 500rpm or 540 rpm. Log this as your golden chart for hitting these PTO speeds.
Amazing deals on this Digital Photo Sensor Tachometer at Harbor Freight. Quality tools & low prices.
www.harborfreight.com
WHY is this very important? With my YM2610, it has the same tach as the YM3110 and others. I run in PTO (2) about 480rpms with engine speed about 1600. This with the 3PT mower gives a great cut and best of all, it SAVES FUEL !!! The best of both worlds, less wear on the mower and to save fuel. This means more seat time and the hour meter runs slower!
This has been a long discussion on the Yanmar Tractor Owners Group. The community members have benefited with the discussions and fuel savings this year as prices are insanely high.
Now for you to go faster, once the PTO has been dialed in, you can pick the PTO selection and engine RPMs to match. Then with the PowerShift in the right band, you can move along nicely at a good clip. Hope this answers your questions.