Nacademus
Gold Member
Everyone has their own ideas on where to run it. There is a fine line between running higher RPM and wasting fuel versus running the engine speed too slow causing lugging and back-feeding the driveline in the occasionally taller stuff. I have under a hundred hours on mine but I've read literally everything I could on these machines and their power-plants. I tend to over-consume technical materials (lol) and there were a few things I needed to educate myself on-thanks to many of the fine folks here. Take what I say with a grain of salt but I will share my thoughts.
I generally run mine right where 540RPM is indicated on the dash-or a touch below if the grass isn't giving me grief. The 540RPM mark is located in different areas on the GC1715/20 dash compared to the GC1705/10 because they have different gearing-obviously.
Initially, a lot of people thought the only difference between the horsepower on these tractors is the fuel flow being turned up. Many elected to get the lower HP tractors and turn the fuel up thinking they saved some money or whatever. That's not necessarily the case.
There are shims for fuel adjustment to make the injector pump flow more which can achieve higher HP-sure, but there are literally differences in the transmission gearing (different part numbers) when converting the engine RPM to useable power at the PTOs. This is read: RPM at certain fuel flow equals XX HP but "RWHP" (lol) or PTO torque output is not necessarily the same due to the gearing. Increasing the lower rated engines created an overrun situation and may traverse that real fat torque curve destined to be sent out the PTO shaft. This is also wasteful with fuel.
Run it where you are comfortable and listen and feel the little diesel. Sense when it is loading up or observe the changes in the puffs of soot output from its exhaust and try and set it to where its consistent based on the work you're doing. You shouldn't ever really "roll coal" during long tasks like mowing-thats kind of lugging them. These are pretty lean diesels.
Doing this should keep you pretty economical with operation and maintenance costs and prove safer for the equipment longevity.
Sorry if this has been beaten to death or answered further up.
I generally run mine right where 540RPM is indicated on the dash-or a touch below if the grass isn't giving me grief. The 540RPM mark is located in different areas on the GC1715/20 dash compared to the GC1705/10 because they have different gearing-obviously.
Initially, a lot of people thought the only difference between the horsepower on these tractors is the fuel flow being turned up. Many elected to get the lower HP tractors and turn the fuel up thinking they saved some money or whatever. That's not necessarily the case.
There are shims for fuel adjustment to make the injector pump flow more which can achieve higher HP-sure, but there are literally differences in the transmission gearing (different part numbers) when converting the engine RPM to useable power at the PTOs. This is read: RPM at certain fuel flow equals XX HP but "RWHP" (lol) or PTO torque output is not necessarily the same due to the gearing. Increasing the lower rated engines created an overrun situation and may traverse that real fat torque curve destined to be sent out the PTO shaft. This is also wasteful with fuel.
Run it where you are comfortable and listen and feel the little diesel. Sense when it is loading up or observe the changes in the puffs of soot output from its exhaust and try and set it to where its consistent based on the work you're doing. You shouldn't ever really "roll coal" during long tasks like mowing-thats kind of lugging them. These are pretty lean diesels.
Doing this should keep you pretty economical with operation and maintenance costs and prove safer for the equipment longevity.
Sorry if this has been beaten to death or answered further up.
