CK30 RPM Normal Drop Under Road Load

[Spanky100]

I have a CK30 HST FEL R4s(not loaded) Box Blade (600 lbs). This is the first time that I have used the HST High range for driving on paved roads. Each time I would set engine RPM to PTO rated notch on tachometer which is 2500 Engine RPM before starting out.

When running full forward speed (HST foot pedal down all the way) on level road the Engine would drop 100 to 2400. Some of the short up grades the RPM would drop a total of 200 to 2300 Engine RPM. Does this seem normal? I was thinking the engine governer might maintain the engine RPM closer to unloaded set engine speed.

When do you get to the point that you should select the next lower HST Range for road transport?

From memory when running a 5 foot rotary cutter in low range over 4 to 5 foot grass type weeds about a 100 engine RPM drop is my experience.

Trying to learn and not abuse the tractor.


Thanks

Wayne

 

[Mousefield]

I have had my CK35 HST R4 tires on a paved road a couple of times, went down about 1,000 feet to box blade around the government mail boxes. Mine will drop a bit of RPM as well. Only had it in high a few times, find the tractor is too bouncy using it to travel around my property in high.

 

[LastSTRAW]

High Range tends to do that on my DK50 as well when going up hill. I am still getting used to the HST but I find that in high range it does bog down from time to time especially with the PTO engaged. I don't have a solution I just live with it.

 

[Dmace]

I was thinking the engine governer might maintain the engine RPM closer to unloaded set engine speed.

There is no governor, you set the engine speed with the hand throttle. I think the drop in engine speed is normal. You don't want to lug the engine too much so keep it above 2000 rpms while operating the HST and it will be fine.

 

[MtnViewRanch]

I have a CK30 HST FEL R4s(not loaded) Box Blade (600 lbs). This is the first time that I have used the HST High range for driving on paved roads. Each time I would set engine RPM to PTO rated notch on tachometer which is 2500 Engine RPM before starting out.

When running full forward speed (HST foot pedal down all the way) on level road the Engine would drop 100 to 2400. Some of the short up grades the RPM would drop a total of 200 to 2300 Engine RPM. Does this seem normal? I was thinking the engine governer might maintain the engine RPM closer to unloaded set engine speed.

When do you get to the point that you should select the next lower HST Range for road transport?

From memory when running a 5 foot rotary cutter in low range over 4 to 5 foot grass type weeds about a 100 engine RPM drop is my experience.

Trying to learn and not abuse the tractor.


Thanks

Wayne

This is most likely a common occurrence with the CK27 & CK30. I would think that the CK35 does not do this. This is part of why there is different HP ranges in the same frame size. Just think how bad this is with a CK27. I would think that if the RPM drops 350-400 RPM that it would be time to shift down.

Just my :2cents:

 

[Alien]

Correct. They are gutless in high gear and it is only a road transport gear more than anything. Mine loses a lot of rpm on a hill or even a slight rise. If it struggles too much just ease your foot off the fwd pedal a bit and allow it to come back to the next ratio until you are past the rise. Personally, I never use mine above 2000 rpm and usually about 1800 and it works fine.

 

[Dmace]

Personally, I never use mine above 2000 rpm and usually about 1800 and it works fine.

If you have an HST then you could be causing harm to the HST pump by operating it at less than 2000 rpms. The manuals as well as dealers and mechanics on this forum all say 2000 rpms is the lowest engine speed for operating the HST.

 

[VictorW]

The rpm drop in high range you mentioned is what mine does also. 30hp, over 3500lbs in weight and a high gear to get some travel speed puts some load on the engine. As Dmace mentioned, no governor to compensate for load.

 

[MtnViewRanch]

If you have an HST then you could be causing harm to the HST pump by operating it at less than 2000 rpms. The manuals as well as dealers and mechanics on this forum all say 2000 rpms is the lowest engine speed for operating the HST.

Is the 2000 RPM what the operator's manual says? With my Mahindra 3215 HST, the manual says to not operate under 1500 RPM. I know, different manufacturer, but I was just wondering.

 

[Mousefield]

If you have an HST then you could be causing harm to the HST pump by operating it at less than 2000 rpms. The manuals as well as dealers and mechanics on this forum all say 2000 rpms is the lowest engine speed for operating the HST.

I find 2,200 to 2,400 RPM is were I operate my CK35 HST.
When using my backhoe I am usually around 1800 RPM.