B2320 Won't maintain RPM Mowing

[BotaBigot]

...do PM on flail mower...

 

[Farmall45b]

That's not productive!

When you say the RPM's drop more then they used to...where you mowing the same field under the same conditions (wet/dry grass 12" high) or did the conditions change?

Same or most likely better conditions. The grass was not as long as it usually is and it was very dry, I often cut when it is slightly wet.

 

[Farmall45b]

How big of flail mower are you running? You have 17 HP at the pto and flails take some horse power to run. I doubt anything is wrong with your tractor. I would look at the mower. Change out the gear oil in the top and side gearcase to a lighter weight. Say a 75-90 synthetic. That might help a little. If your knives are dull they are tearing instead of cutting that might be your whole issue. Imagine trying to cut a rope with a butter knife instead of a hunting knife. Requires a lot more force and now your engine is trying to cut the grass with a butter knife.

It is a 50 inch flail. After looking at the flail hammers, they are pretty worn. Certainly not the straight knife edge that was there when I bought the mower.

 

[Farmall45b]

Changed the flail hammers on the mower, they were not too bad a few beat up. Also put fresh diesel in. All is well not, mows very well with plenty of power. I think the fuel was my issue. It is also possible that in my hurry to get mowing last time I may have put the PTO lever into 960 RPM instead of 540 RPM which would have caused lower power too.