Rated power of CK20 engine

[IslandTractor]

I was wasting a little time today looking at the Kioti website and checked out the specs on the 3C093A engine that Kioti says is in my tractor. In one place they give the HP as 21 at 2800rpm but in the more detailed engine section the horsepower ratings were confusing as it indicates 19hp at 2800rpm and 21hp at 3600rpm. The CK20 has normal PTO speed at 2800rpm on the tachometer. I have never run the engine at greater than 2800rpm but now I am wondering what the rated RPM and power of this engine really are. I am familiar with identical engines being rated at different HP and RPMs for continuous vs medium or intermittent duty but now I am confused about just what HP the CK20 is and what the rated RPMs are. Any ideas to explain this?

 

[Dmace]

I highly doubt that engine is only putting out 19 hp at the engine at 2800 rpms yet still laying down 16.5 hp at the PTO at the same 2800 rpms. If so, that is one efficient system.

 

[IslandTractor]

I agree. However what really struck me was the 3600RPM rating given to the engine. I have never thought of going up that high as I assumed power peaked around 2800. Is anyone running the CK20 at 3600 even for a short while? There are certainly times when a little extra power would be nice for a few minutes and if 3600 is safe as an intermittent rating it would be nice to have that confirmed.

 

[Bob_Skurka]

Any ideas to explain this?

Ed, not sure how Kioti measures things, but as for horsepower ratings there seems to be no real consensus on how to measure it and then report it. Obviously there is PTO HP and we all pretty much agree on what that is. But then there is Engine HP, Drawbar horsepower, Peak horsepower, Rated horsepower, Developed horsepower, Maximum horsepower, etc.

Some tractor manfucaturers rate their equipment with the engine HP rating, ignoring (misrepresenting, ignoring ) the fact taht this energy must be transferred through a drivetrain. Some may make up unrealistic test conditions to encourage one brief measurement of high HP to make a claim.

I always ignore any "dyno testing" of a raw engine because, for real world use, an engine connected to a dyno is pretty pointless. You and I use engines that are connected to a drivetrain and a PTO.

I would simply guess, and it is nothing more than a guess, that Kioti is trying to be honest about their engine and provide multiple ratings. For example, it might be 21hp on a dyno but 19hp useable at the drawbar?

 

[IslandTractor]

Bob, I understand your points too. I guess my real question is whether this engine is really rated up to 3600rpm for intermittent use and if that is where the highest horsepower would be. As stated earlier, I've never considered going up that high but I wonder if there would be any harm in doing so. The Kubota BX engines are rated up to about 3600 I believe and 3600RPM is pretty standard for small diesel generators.

The Kioti website data seems inconsistent and on their engine page (HOME > PRODUCTS > Engines > 3C093A) they list both 19hp at 2800 and 21hp at 3600rpms in the data but the power curve graph only goes up to 3000rpm where it is also graphically showing only 19hp.

Just realized that they actually list the CK20 engine (3C093A) as two separate ratings and sizes...if you look closely at the engine page data/specs there are two different sets of dimensions and two different oil capacities. One is 19hp at 2800rpm and the other is 21hp at 3600rpm. Looks like the engine is set up slightly differently (I presume medium and intermittent power ratings) with 19 and 21hp respectively. That is still a bit confusing as I've always thought of the CK20 as 21hp but maybe it is really a 19hp tractor.

Any of the dealers out there know which version of the engine is actually in the CK20??

 

[Highbeam]

So really, you just want to know what the redline is. I suspect the injection pump is governed not to exceed a particular RPM as the cummins is, for example.

 

[IslandTractor]

So really, you just want to know what the redline is.

Kinda but I would also just like to understand what the real rating of the engine is and whether it is appropriate to exceed 2800rpms. I guess I could find out if it is governed easily enough.

I know I have occasionally spun the engine up beyond 2800 (when I adjust throttle to 2800 under load and then release whatever the load was) but I immediately throttle back. If I would get more work out of the hydraulic pump at higher RPM I'd like to know it especially when trying to pop trees out by curling the grapple.

 

[Bob_Skurka]

If I would get more work out of the hydraulic pump at higher RPM I'd like to know it especially when trying to pop trees out by curling the grapple.

Ed, probably not going to get more out of the FEL than you already get because there are pressure settings in your hydraulics so even if you can theoretically get the output, the relief setting will not let you use it. I'm sure many loader control valves have their own limiters too, so if your loader has a pressure regulator or some sort of pressure relief setting, then not matter what your theoretical input, it only allows what is set to accept to pass through the system. Without that you'd run the risks of blowing hoses and fittings from too much pressure, and a pin size spray of hydraulic fluid is a very dangerous thing and can easily puncture your skin and kill you or make you very ill.

 

[IslandTractor]

Good point.

 

[Highbeam]

I don't think you could pull a bigger tree out with RPMs but you could maybe increase the flow rate so that the cycle times go down.