USING RPM to clear Disel buildup?

[Orange man hero]

Last spring I get a LX2610. I avoided the next bigger tractor/engine, the 3310 because I read that some other folks avoided the 33 bigger engines because of the hassle of the system it has to clear diesel fuel residue buildup. I have been using throttle rpm to run up the engine in hopes that it will burn off buildup. Does this seem logical?
I only run on average 1500 rpm. After about 20 minutes plowing snow, I sit there and rev it up to 2000 to 2600 rpm for minutes at a time. Does this make sense to anyone or am I just wasting my time and fuel?

 

[85Hokie]

Worse thing you can do to a diesel engine is run it at a low rpm WHILE making it work hard.

AS for fuel - many diesels will get a bit better fuel "mileage" when working 60-70% of the WOT than it will at idle or slightly above.

Babying a diesel is a thought that the mind and user needs to move past.

When plowing snow ( I did that today) I would be 75% or better in the WOT range - less is not more!

Look up diesel "slobber" or wet stacking to get a better understanding of what is going on inside at a low RPM.

 

[Botamon]

Do the machine - and yourself - a favor. Once it is warmed up, run the rpms up above 2000 rpm. Not sure about your particular model but somewhere about where it would turn the PTO at 540 rpm would be good. Diesels do best when they run hard. Your hydraulic pump is rated to run most efficiently at a certain rpm also - and it is not running efficiently at a high idle. My 60 year old John Deere diesel will not come up to operating temperature - open the thermostat - if I run it at idle or fast idle. My new Kubota's owner's manual specifically warns against running low engine rpms for extended periods. I know it is hard to listen to the high rpms - I had to get used to that also - but really, it is best for the tractor.

 

[sheepfarmer]

This model will work well in the snow if you put it in low gear and set the rpm as mentioned above at around 3/4 wot. This will give you a controllable speed with the hst and keep from lugging the engine. No need to stop it and run the rpm up. If you have a pto driven implement run at recommended rpm, and choose forward speed with gears.

 

[lugbolt]

what cools a diesel engine

water around the cylinders? yes...but that's not all.

AIR coming into the engine also cools the engine, specifically the piston crowns and the valves and cylinder head.

Air flow increases with RPM, therefore cooling increases too-as does the engine efficiency

kubota designed the engine to run at a certain speed, if it was designed to run 1500 rpm, the governor would be 1800. IIRC rated horsepower is at 2500 or so on the LX2610

Lugging the engine, shortens it's lifespan. Now lugging being defined as lower RPM with significant load on it (plowing at 1500 rpm would be an example).

I would imagine they tested the engine at, say 2500-3000 rpm for many hours nonstop, so don't be afraid to run it. Ain't gonna hurt it unless you run it out of oil or plug the air filter, or overheat it somehow

 

[Orange man hero]

what cools a diesel engine

water around the cylinders? yes...but that's not all.

AIR coming into the engine also cools the engine, specifically the piston crowns and the valves and cylinder head.

Air flow increases with RPM, therefore cooling increases too-as does the engine efficiency

kubota designed the engine to run at a certain speed, if it was designed to run 1500 rpm, the governor would be 1800. IIRC rated horsepower is at 2500 or so on the LX2610

Lugging the engine, shortens it's lifespan. Now lugging being defined as lower RPM with significant load on it (plowing at 1500 rpm would be an example).

I would imagine they tested the engine at, say 2500-3000 rpm for many hours nonstop, so don't be afraid to run it. Ain't gonna hurt it unless you run it out of oil or plug the air filter, or overheat it somehow

OK GUYS Thanks and I will be increasing RPM next job.

 

[Orange man hero]

OK, next time 2000 rpm here we go!!!

 

[85Hokie]

OK, next time 2000 rpm here we go!!!

You'll not hurt that engine - as mentioned, it was designed to run at "X" rpms - other than added noise, it is the best thing to run it hard.

 

[NCL4701]

I’ll have to admit when I first got the new Kubota going from thousands of hours with the 1940’s and 50’s gassers to the Tier 4 diesel was a bit disconcerting. I knew what RPM the diesel preferred and ran it there, but being used to engines that topped out in the 1600 RPM area and preferred more around 1000 it “felt” like abuse to run 1800 to 2400 RPM. After a couple hundred hours I got used to it.

 

[NHSleddog]

The LX2610 does NOT have a DPF in it. Run it at any appropriate RPM you want.

 

[Broncbob]

What, if any emissions equipment does it have? If you have a Particulate filter in the exhaust, you definitely want to run at over 2000 RPM. The filter clogs due to soot, and you will soot far more at low RPM. The filter is cleared by heat during a regen cycle.

 

[Lonesouth]

The LX2610 does NOT have a DPF in it. Run it at any appropriate RPM you want.

wet stacking can still be an issue without emissions equipment.

 

[ACDII]

Every diesels air intake is at WOT, no butterfly to regulate it so it will draw all the air it needs. It's the amount of fuel being injected that determines it's speed. At idle it takes very little fuel to run, so it can sit and idle all day on less than a pint of fuel, unless worked, then the governor adjusts the fuel rate to keep the RPM's up at the idle speed. Since it takes only a tiny bit of fuel to raise RPM's it can cause too much fuel to be dumped in, and while there is plenty of air coming in, in order to get enough for each cylinder to burn, the RPMS have to go up, but since its set to idle, the governor will quickly cut fuel as it ramps up. Not good for the engine. You get fuel build up, and can cause cylinder wash down, and get into the oil.

Running at or near PTO power provides the proper air/fuel ratio, so far less of any chance of fuel washdown, and expelling fuel into the exhaust. After a long working idle or low speed, raising RPMs up wont help burnoff the excess unless you are working it hard to raise EGT. It is best to run it at PTO power levels when doing work, and very little idle time unless it is parked and not being worked, not even moving around.

On Tier IV, the regen cycle injects diesel fuel into the filter to help burn off the soot, but engine parameters are built in to maximize the heat from the exhaust to fully burn off the fuel, something a non tier IV can't accomplish.

 

[Orange man hero]

I’ll have to admit when I first got the new Kubota going from thousands of hours with the 1940’s and 50’s gassers to the Tier 4 diesel was a bit disconcerting. I knew what RPM the diesel preferred and ran it there, but being used to engines that topped out in the 1600 RPM area and preferred more around 1000 it “felt” like abuse to run 1800 to 2400 RPM. After a couple hundred hours I got used to it.

Yes, I struggle with that also. I had a 47 Ford Flatbed that I used for gyppo logging back in the 70's. Those flatheads had a lot of torque and power at low rpm. I know it is not a Diesel. Also above 1600 for the LX2610 seems unnecessary and puts a lot of added strain on the running gear. But I will try it for a while. For small lifting jobs I even run it at idle as it makes using the bucket to lift smoother it seems not so prone to jerk the bucket. And then you also have to factor in the added fuel consumption over time compared to the extra strain on the engine. Especially with the new idiotic fuel prices.

 

[Orange man hero]

Every diesels air intake is at WOT, no butterfly to regulate it so it will draw all the air it needs. It's the amount of fuel being injected that determines it's speed. At idle it takes very little fuel to run, so it can sit and idle all day on less than a pint of fuel, unless worked, then the governor adjusts the fuel rate to keep the RPM's up at the idle speed. Since it takes only a tiny bit of fuel to raise RPM's it can cause too much fuel to be dumped in, and while there is plenty of air coming in, in order to get enough for each cylinder to burn, the RPMS have to go up, but since its set to idle, the governor will quickly cut fuel as it ramps up. Not good for the engine. You get fuel build up, and can cause cylinder wash down, and get into the oil.

Running at or near PTO power provides the proper air/fuel ratio, so far less of any chance of fuel washdown, and expelling fuel into the exhaust. After a long working idle or low speed, raising RPMs up wont help burnoff the excess unless you are working it hard to raise EGT. It is best to run it at PTO power levels when doing work, and very little idle time unless it is parked and not being worked, not even moving around.

On Tier IV, the regen cycle injects diesel fuel into the filter to help burn off the soot, but engine parameters are built in to maximize the heat from the exhaust to fully burn off the fuel, something a non tier IV can't accomplish.

Good Info!!!

 

[Orange man hero]

Good Info!!!

I never use PTO so what is PTO power levels?

 

[NCL4701]

Yes, I struggle with that also. I had a 47 Ford Flatbed that I used for gyppo logging back in the 70's. Those flatheads had a lot of torque and power at low rpm. I know it is not a Diesel. Also above 1600 for the LX2610 seems unnecessary and puts a lot of added strain on the running gear. But I will try it for a while. For small lifting jobs I even run it at idle as it makes using the bucket to lift smoother it seems not so prone to jerk the bucket. And then you also have to factor in the added fuel consumption over time compared to the extra strain on the engine. Especially with the new idiotic fuel prices.

The extra fuel consumption is a bit counterintuitive with the computer controlled diesels. I’ve found with mine fuel consumption is directly related to load but not so much related to RPM as it is with older mechanical diesels or carberated gas engines. Mine takes very little fuel running at higher RPM with light loads. Chipping near capacity or running the rotary cutter through heavy sawgrass, the tone of the engine changes to something more throaty and it starts drinking the fuel pretty quick. Just running the loader or grapple at higher RPM fuel economy doesn’t seem to be negatively impacted to the degree I would have expected out of an older engine.

 

[NHSleddog]

wet stacking can still be an issue without emissions equipment.

Sure, but it didn't start with DPF's (which his tractor does not have).

He has the same issues every old diesel around the world has, and can run it like one, no special treatment needed.

Ask your local dealer how much "wet stacking" he sees on CUT's - lol.

 

[jimh406]

I run my L2501 at low RPMs from time to time. I really don't think you'll have any issues with a non turbo no Cat and no DPF engine. However, if someone can post a few cases where someone has had issues, I'd be happy to see them.

 

[Pony Doc]

Re: PTO RPM check your owner's manual for specifics. Most older gear tractors have an index marker on the tachometer labeled 540, that indicates 540 RPM at the PTO