How to run a Diesel Engine

[sparkyjohn]

Just picked up a new Kioti CX2510. 24.5hp diesel engine. Never owned a diesel so i need to learn. How do these engines like to be run?
The book says when cold, after the glow plug light goes off, start and let idle at low RPM for a few minutes to warm up. This i understand.
What i need to know is when running and using do these tractors like to be left running or is turning on and off ok? I see to use the rear PTO it must be at the red mark [2600 rpm] so should i always run at this mark or is running at higher or lower rpm's ok when driving? If i am on and off, is letting it idle ok or should it be left at a higher idle? I know proper use will help an engine last longer. I understand gas engines very well so if i should treat it the same as i would a gas engine then i am good to go. Thanks.

 

[combustor]

I've got the Kioti CK35. You're good in that your tractor like mine has no emissions junk so the general operation is less temperamental.

Once you let it warm up as suggested, it doesn't mind being run hard. Most PTO implements need to be run at rated RPM, because lower RPMs can actually increase torque to the propeller shaft and break it when the implement is under high load. If the PTO implement is under no/low load then lower rpm won't hurt anything.

Letting it idle at low rpm is fine, and I just leave mine running when I'm on and off a lot. If you were to idle it for hours at a time you COULD experience something called "wet stacking" which is endemic to diesels with mechanical injectors like ours. This is potentially bad for the engine but a minor case can be cleared up by running the engine at maximum power to burn off the black goo and carbon accumulated in the combustion chamber and exhaust stack and it will be cured.

Change the oil at recommended intervals, let it warm up before going to full power, and then just use it. It will last longer than you.

 

[ericm979]

Run at PTO RPM when using an implement. Most tractors' torque curve peaks well before PTO RPM. The reason for that is called "torque rise"- the engine is designed so if the load slows the engine down, there is more torque to resist that force. For example my Branson's PTO RPM is 2500 but the torque peak is around 1600.

With my old non DPF tractor I would turn it off if I got off to do something for more than a few minutes, so I would not be breathing stinky diesel exhaust. With the Branson I turn it off under the same conditions so it won't clog up the DPF. Turning it off and starting it back up doesn't hurt it.

When I start when it's cold, I let it idle for 10 seconds or so to make sure oil is getting everywhere, then bump up the rpms to 1200-1500 so it will warm up faster. Often I drive it to where I will be working it to finish the warmup. Diesels run cool at idle so it takes them longer to warm up than gas engines.

When you start it always let the glow plug cycle complete before engaging the starter.

 

[SylvainG]

Don't forget about the hydraulics too. When it's cold outside (you don't say where you're from), it needs to warm up before you should use it. And don't forget your hour meter doesn't care if it's idling or running at PTO speed, an hour is an hour so you'll do more frequent maintenance if you keep it running idle for no good reason.

 

[sparkyjohn]

Don't forget about the hydraulics too. When it's cold outside (you don't say where you're from), it needs to warm up before you should use it. And don't forget your hour meter doesn't care if it's idling or running at PTO speed, an hour is an hour so you'll do more frequent maintenance if you keep it running idle for no good reason.

I do live in the north, so letting all the oil's warm up and move around is important.

 

[Industrial Toys]

You shouldn't stress a cold system, but on the other hand, "gently" using something is often the easiest way to warm it up. I sometimes start driving in the lowest gear/range at just a crawl. It's boring but not as boring as sitting there stationary waiting for the thing to warm up.

 

[rademamj1]

Throughly read your Kioti operators manual, and that will go along way in good operational procedures for your tractor.

 

[the old grind]

... Most tractors' torque curve peaks well before PTO RPM. The reason for that is called "torque rise"- the engine is designed so if the load slows the engine down, there is more torque to resist that force. For example my Branson's PTO RPM is 2500 but the torque peak is around 1600.

With my old non DPF tractor I would turn it off if I got off to do something for more than a few minutes, so I would not be breathing stinky diesel exhaust. With the Branson I turn it off under the same conditions so it won't clog up the DPF. Turning it off and starting it back up doesn't hurt it.

When I start when it's cold, I let it idle for 10 seconds or so to make sure oil is getting everywhere, then bump up the rpms to 1200-1500 so it will warm up faster. Often I drive it to where I will be working it to finish the warmup. Diesels run cool at idle so it takes them longer to warm up than gas engines.

When you start it always let the glow plug cycle complete before engaging the starter.

All of this mirrors what I've learned in 20 yrs with four 1.3-1.7L 3 cyl CUTs.

Don't forget about the hydraulics too. When it's cold outside (you don't say where you're from), it needs to warm up before you should use it. And don't forget your hour meter doesn't care if it's idling or running at PTO speed, an hour is an hour so you'll do more frequent maintenance if you keep it running idle for no good reason.

This too, and where Winter is a bear the engine will usually warm up more quickly than the hydro & HST oil. The main reason I prefer to limit cold weather operating is because of the growl from the HST while 'exercising' the FEL to load the pump and motor to warm things up. At >20 deg everything is easier.

I do live in the north, so letting all the oil's warm up and move around is important.

While my hydro and input filters are separate there is some sharing of fluid, as in one dipstick for both. It takes longer for the FEL growl to quiet down than the HST.

As for wet-stacking or frequent regens (NA to OP), the torque peak rpm pretty much represents the tuning and timing of injector pump and cam, along with volumetric efficiency. I suggest a minimum idle rpm of 12-1300 according to whether the fenders rattle etc, and limit warmed up idling to 15 min or so. Many of us do most of our work in the 18-2200 rpm range except PTO stuff I suspect because we just get into a groove there and everything else works. Diesels are designed to run hot and hard. We're being easy on 'em when we don't do that, just don't want to go too far.

 

[oosik]

The only words of caution in my 2009 Kubota Op Manual - "do not put the tractor under heavy load until it has fully warmed up". "Do not operate the tractor at full speeds or put the tractor under heavy loads for the first 50 hours of operation". Common sense .........

 

[RandyT]

Don't forget about the hydraulics too. When it's cold outside (you don't say where you're from), it needs to warm up before you should use it. And don't forget your hour meter doesn't care if it's idling or running at PTO speed, an hour is an hour so you'll do more frequent maintenance if you keep it running idle for no good reason.

Not true on older mechanical hour meter/tachs. If rated at 2600 but idles at 1300 would run 2 hours to show 1 on hour meter.

 

[RalphVa]

Just picked up a new Kioti CX2510. 24.5hp diesel engine. Never owned a diesel so i need to learn. How do these engines like to be run?
The book says when cold, after the glow plug light goes off, start and let idle at low RPM for a few minutes to warm up. This i understand.
What i need to know is when running and using do these tractors like to be left running or is turning on and off ok? I see to use the rear PTO it must be at the red mark [2600 rpm] so should i always run at this mark or is running at higher or lower rpm's ok when driving? If i am on and off, is letting it idle ok or should it be left at a higher idle? I know proper use will help an engine last longer. I understand gas engines very well so if i should treat it the same as i would a gas engine then i am good to go. Thanks.

On our old 240D Benz, it liked to be run full throttle, and you had to do it with it because it had only 65 hp.

I ran the JD 4010 (like a 2019E if one were made today) at its approximately 3,000 rpm for 540 PTO speed because I needed all of its 18.5 hp.

On both the 1025R and the 2025R with their excessive 24.5 hp, I ran them at 2,500 rpm for PTO work and 2,000 rpm for general FEL work. For digging in soft dirt with the FEL, I'd run rpms up to around 3,500 rpm near max for them.

You mainly want get up onto the relatively flat torque "curve" for your diesel engine. For our VW TDI when we had it for nearly 7 years, it was 1,500-5,000 rpm. NEVER wanted to let it drop below 1,500 because of torque curve from the turbo.

Ralph

 

[RalphVa]

Oh, on all our diesels, 7 of them, they were started and run. Not full throttle until warmup but enough to do most work, locomotion. Don't just let them sit and warmup.

The Isuzu diesel generator driver is always started and made to run at full speed immediately. Of course, "full speed" on it is probably "fast idle" to JD, which is about 1,600ish rpm, which is where the 1025R idled at.

Ralph

 

[tibadoe]

When I fire up my tractor I let it idle for about a minute to get the engine oils circulated. Then I bump up the throttle in small steps. Back out of the garage and take it easy until at normal operating temps. I also cycle the FEL a couple times while heading to work location to help circulate the fluids. I don't need to operate tractor below 30* so it only takes about 5-6 minutes for engine to be at normal operating temp - hydraulics maybe about 10 minutes. Once warmed up it's time to roll.

Read manual, keep an eye on all fluid levels, perform all PM work as listed in maintenance schedule at a minimum. Tractor will usually outlast you.

 

[mred2]

And when you put the PTO in gear, slow the rpm down first. After it is in gear, bring the rpm's up to operating speed. Putting it in gear at full speed will shear pins and can do damage.

 

[Doc G]

OP has a good question which I remember pondering as well. I've only owned one diesel engine (my current tractor) but in the years I've owned it, the biggest factor in how it operates at start is simply the ambient temperature.

We rarely have super cold weather but when we do, it takes more time for the engine come up to operating temp and MUCH more time for the hydro fluid to loosen up. My rule of thumb for cold temps: don't work hard or rev over 50% PTO speed till the temp gauge starts moving.

On the other hand when it's 80/90/100+ outside, I can fire up and start working almost immediately. Bottom line, though, I suspect each machine is a little different. You'll learn the quirks of yours pretty soon!

I turn off and on frequently in warm weather; leave running in cold.

 

[deezler]

Lots of good advice here!

 

[SylvainG]

Not true on older mechanical hour meter/tachs. If rated at 2600 but idles at 1300 would run 2 hours to show 1 on hour meter.

Cool, mine is 'mechanical' (it has the old style digit wheels). That's something I'll look for next time I let it idle for 20 minutes because it's 0F.

 

[the old grind]

Not many cable-driven tachs since 2000.

My ZTR has a digital hour meter that only counts hours the blades are engaged.

Apples, oranges, and grapes, so ...

 

[sparkyjohn]

Lots of good advice here!

Yes. I am now getting comfortable running my new tractor. Thanks all for the good advice.

 

[LittleBill21]

I tend to go against the grain, 10 seconds in you already had full oil pressure for 9 seconds. warm up is a joke for me, at 15f, i changed the fluid in my hst/hydro, the tractor ran 45 minutes at 1500rpm and the fluid was cold when i drained it.

my tractor won't even show heat on the coolant for 15 minutes working it in cold weather. idling would be a total waste. I also don't floor off the start, just be logical, it should make sense of what works or doesn't.