Engine Warm up?

[troverman]

diesels do not warm up unless they are reved up and are under load.

Totally false. I started my Kubota MX4800 today and let it simply idle for about 10 minutes. The temp gauge moved to the half-way position. Why wouldn't it? It has a thermostat and burning diesel in the cylinders creates heat.

 

[DK35vince]

Totally false. I started my Kubota MX4800 today and let it simply idle for about 10 minutes. The temp gauge moved to the half-way position. Why wouldn't it? It has a thermostat and burning diesel in the cylinders creates heat.

Yes, So does my tractor, and so does every diesel I run every day at work..

 

[RalphVa]

Never gave this a thought on our VW TDI. Just started it and immediately moved it out of the garage.

Only thing I'd worry about on the tractor in really cold conditions is the hydraulic system. In the frozen north, I think I'd go for an underneath heater put underneath the HST about 15 minutes or so before starting. I'd not worry about the exhaust system catalytics at all.

You're in Maryland. I'd just start it at something like medium idle and then go.

Ralph

 

[Boondox]

Depends on conditions. I move a lot of snow in winter. We don't get the house-burying lake effect like some areas, but snowfall is pretty steady from late November till late April. It usually comes a few inches at a time to refresh the snow pack, which is why members of the US Olympic Nordic Ski Team train here. When the temps dip into the single digits the snow is light powder and the wind blows it around making me plow the 500 yard driveway a few times a day. Last winter we had six weeks of 30 below night temps with daytime highs at or below zero so a block heater is a must. In those conditions I'll let the tractor warm up for a good 20 minutes before moving it out of the carport. But warming the engine doesn't do much for the hydraulic fluid, so I drive slowly to the end of the driveway to get it flowing before starting the heavy work of snow removal. It usually takes 15 minutes of use before I feel any heat coming out of the cab vents.

In summer I give it two minutes to warm up.

 

[MechanicalGuy]

In gas engines, warm up is typically to protect the valve springs from brittle fracture. You want the spring to be at operating temperature before revving it high and stressing it cold. On a diesel the springs won't ever see a high revving rpm...so I'm not sure what warm up is safeguarding as long as there is oil pressure. Anyone have any guesses?

 

[LouNY]

When I warm my diesels in the winter it has several benefits in my mind;
1) the pistons have a chance to warm up which reduces piston to wall clearances, resulting in much less noise, piston slap.
2) the oil has been circulating and warming up the entire engine which is resulting in more uniform oil flow with less pressure and the pressure relief is not opening as much so more oil is circulating.
3) the hydraulic pump on my open center equipment has been circulating and warming up, my hydraulic controls respond smoother and easier.
4) depending on the tractor or truck I may run the transmission, I'll put one transmission in neutral the others in gear and clutch out or shuttle shift engaged which further circulates and warms the system.
5) after a warmup period the tractor or truck just feels better, runs smoother, responds better, and the controls feel and function better.

6) the biggest one I feel that my equipment will last longer work better and be nicer to me if I am to it.

I also use block and manifold and reservoir heaters as well as synthetic lubricants and blended and treated fuels.
I would much rather stay in the cab working then be outside working on the equipment.
Also I'm sure I missed several reasons to.

 

[Cougsfan]

I think the op's question was in reference to the DPF. Prolonged warming up of a Non-DPF 's may be perfectly acceptable where-as it may cause problems with certain DPF's. Personally, if it is warm out, I just start it up and run it, no warm up. In cold weather I will let my rig idle for 20 -30 seconds then run the revs up to 1500 for another minute or so until I see the temp gauge start to move. Truthfully, with modern synthetic multi-grade oils, I don't think that warming up the tractor is nearly as critical as it was back in the day. Unless it is really cold, the oil in the hydraulic systems stays pretty thin, and warming the engine in the tractor up does little for it.

 

[buickanddeere]

In winter when the temps are near or below freezing . The diesels are plugged in and they start like summer . Sometimes at startup the temperate gauge is up off the bottom peg.
Idling to warmup becomes a mute point .

 

[MH8675309]

diesels do not warm up unless they are reved up and are under load.

I'm under the same impression. The hydraulics no doubt suffer worse than the engine - in really cold weather. Someone else said to idle the engine after work. I do if it is running at high throttle for a time - cutting or baling hay - it only makes sense to throttle it down and cool it off a bit before shutting the machine down.

 

[Gary Fowler]

I solved the whole problem of warmup in the winter, I just dont use it when it is cold. I sit inside and have a coffee. In spring, summer and fall if I use it, I let the oil pressure build up at idle for maybe 30 seconds, then raise the FEL and or backhoe components as needed and back out of my shed. I then raise the RPM to 1200-1500 and drive off slowly to do any work which is always a minute or two from my shed. By the time I get there, the tractor is warmed up and all the hydraulics work properly. I have no turbo on any of my machines so cool down is accomplished by lowering the RPM to 1200 on the return to the shop shed. As soon as I lower the FEL, it has cooled as much as I am going to cool it. I do the same thing with my lawnmowers, lower the RPM upon the return drive to the storage shed where it is idled down for 30 seconds or so and stopped. The OEM manual on my Kawasaki engine says to idle it for 2-3 minutes for cool down. Any longer is a waste of engine time and fuel.

 

[mmranch]

-7 here this morning at 9500ft.

My tractor stays in a heated shop in winter. Block heater is plugged in awhile before starting. Idles for 10 to 30 minutes (depending on what else I'm doing). Then elevated RPM with slow hydraulic warm-up routine before I even move the tractor. Then it's full RPM and to work.

So far...so good!

 

[RalphVa]

The VW TDI never had any warmup requirement. Just started it up in all kinds of weather and almost immediately took off.

Only benefit I see to warming up a tractor is to maybe warm up its HST oil a bit. Use the low vis stuff, and it ought to be good to go. Just keep the revs down below 2,000 rpm for maybe the first 5 minutes. Probably be the time you need to get to where you're going to do the real work.

Use 0w or (at worst) 5wxx oil to get immediate oil throughout the engine, even in the coldest temperature. Even at -40 C/F, oil will be sent to the top end of the engine within a couple seconds. If you run 10wxx and 15wxx oils at low temperatures, your engine top end will starve for oil for probably the first 30 seconds or so, maybe more if it is really cold.

Ralph

 

[troverman]

I'm changing my tune a little bit. I bought a new L4060 HSTC this late fall, and I'm using it for plowing duties around the house. In order to get meaningful heat in the cab, the engine needs to be revved up. Oddly my MX4800 would warm up in cold weather just at idle. The L4060 has the same engine but will not warm up. It could be the heater core and longer circulation hoses are having an over-cooling affect on the engine, I don't know.

I often start it up and let it idle at 1500 RPM for 10 minutes or so, in an effort to get some heat and defrost the windshield.

My first regen was at 22 hours which is pretty low, but with this much idling it doesn't surprise me.

 

[BTDT2]

I don't strictly follow the manual's recommendations, but here they are for an L3301 (same as my L4060 and previous L3410) .
HST warmup is likely much more important in even moderate cold temps.
View attachment 614972

I find your chart very strange as my Kubota HSTC 4240 manual has a chart that starts at -10C (14 F) and a warm up time of approx 5 minutes, at -15C to -10C 5 to 10 minutes, and below -20C (-4 F) Kubota recommends more than 20 minutes in warmup time. There is no mention of idling as a part of warm up time, so I interpret warm up as a common sense approach of low power and light loads and not high power until after warmup criteria is met. I think the use of synthetic oils in extreme cold conditions also provides a huge advantage in rapid oil flow to critical parts.

 

[RalphVa]

I have a L3301 Kubota with a DPF exhaust filter. It is recommended not to idle the engine. My question is; how long do you warm up the engine on the L3301 and what rpm?

Just start it up and go as soon as the idle keeps from shuddering. That's what I always do and what we did on our VW TDI with DPF. Actually, it never shudders. Just started and pulled it out of the garage. Just don't hit it with very high rpm until you get to where you need to do some work. Tractors don't rev very highly anyway. You just hear them more readily and think they're working harder than a car/pickup. VW TDIs rev to 5,000 rpm just like a turbine. You really cannot rev your tractor engine too highly to hurt it. With HST, it can put up some fairly high pressures with cold fluid, but that is what the relief valves are in there for; aren't they?

Ralph

 

[big bubba]

seems to me whatever warm up method you choose, it's equally or more important to avoid successive cold short runs on a diesel (esp a new engine) when tasks are less than 20 minutes & the drive train does not fully warm up other than the operating coolant temp
diesels are meant to work steady & hard. imho numerous short cold runs may be harder on engines than debating warm up methods.

 

[LouNY]

Just start it up and go as soon as the idle keeps from shuddering. That's what I always do and what we did on our VW TDI with DPF. Actually, it never shudders. Just started and pulled it out of the garage. Just don't hit it with very high rpm until you get to where you need to do some work. Tractors don't rev very highly anyway. You just hear them more readily and think they're working harder than a car/pickup. VW TDIs rev to 5,000 rpm just like a turbine. You really cannot rev your tractor engine too highly to hurt it. With HST, it can put up some fairly high pressures with cold fluid, but that is what the relief valves are in there for; aren't they?

Ralph

Enjoy running your equipment your way. It is not the way mine has been or will be run.

In cold weather (below 30F) every engine gets at least a minute, car, truck, tractor, lawn mower, even the chainsaw gets a warmup before it gets used.
The colder it gets the longer it goes, every radiator gets covered when it gets colder, that it not so much for the radiators as it is the associated coolers stacked in front of or behind the radiators.
If the hydraulics moan when using them it gets a few more minutes and unloaded exercise. They are not being warmed up at low idle once started the idle is slowly bumped up to 1200-1500 rpm whatever that piece of equipment feels the best at. This doesn't matter if its gas or diesel. Back when it was a propane tractor it had to be warmed up on the bypass till it had water heat for the vaporizer.

So different strokes for different folks, I will continue to advocate for warming up equipment.
PS. I also run synthetic lubricates ad have since the mid to later 70's.

 

[K5lwq]

Enjoy running your equipment your way. It is not the way mine has been or will be run.

In cold weather (below 30F) every engine gets at least a minute, car, truck, tractor, lawn mower, even the chainsaw gets a warmup before it gets used.
The colder it gets the longer it goes, every radiator gets covered when it gets colder, that it not so much for the radiators as it is the associated coolers stacked in front of or behind the radiators.
If the hydraulics moan when using them it gets a few more minutes and unloaded exercise. They are not being warmed up at low idle once started the idle is slowly bumped up to 1200-1500 rpm whatever that piece of equipment feels the best at. This doesn't matter if its gas or diesel. Back when it was a propane tractor it had to be warmed up on the bypass till it had water heat for the vaporizer.

So different strokes for different folks, I will continue to advocate for warming up equipment.
PS. I also run synthetic lubricates ad have since the mid to later 70's.

This is the best answer!

My grandfather, every morning around 7am, would start is old car and hold the pedal to the metal for 1 minuet exactly. We told him many times that was a bad idea. However, he got away with that for many years. In fact, that is how we found out he had passed. The Neighbors knew something was wrong when they did not hear his old car.

My brother inherited his car and the old 327 came apart on him within 2 weeks. :laughing:

 

[ovrszd]

Enjoy running your equipment your way. It is not the way mine has been or will be run.

In cold weather (below 30F) every engine gets at least a minute, car, truck, tractor, lawn mower, even the chainsaw gets a warmup before it gets used.
The colder it gets the longer it goes, every radiator gets covered when it gets colder, that it not so much for the radiators as it is the associated coolers stacked in front of or behind the radiators.
If the hydraulics moan when using them it gets a few more minutes and unloaded exercise. They are not being warmed up at low idle once started the idle is slowly bumped up to 1200-1500 rpm whatever that piece of equipment feels the best at. This doesn't matter if its gas or diesel. Back when it was a propane tractor it had to be warmed up on the bypass till it had water heat for the vaporizer.

So different strokes for different folks, I will continue to advocate for warming up equipment.
PS. I also run synthetic lubricates ad have since the mid to later 70's.

I agree.

The DEF JD Grader that I run needs considerably more warm up than it's pre-DEF predecessor. Worst part with the Grader is it's cooling efficiency. All of the coolers are separated and not stacked. The engine will warm up due to the thermostat. I struggle to get the hydraulics and trans fluid warm. I run hydraulics constantly during the 3 or 4 minutes of warm up to try to get some warmth. Everything functions a bit "stiff" for the first 15 minutes of operation. I don't like that period. I'm gentle with the machine until all of the fluid temps are up into the operating range.

 

[dodge man]

I have never been a fan of long warm ups. I let my tractor warm up a minute or two and my truck just 10 seconds or so. On frosty mornings I let my truck warm up longer because I am to lazy to scrap the windows.