Correct engine idle speed during warm up??

[GManBart]

I shut it off with the engine at about 1400 rpm and leave it there. That's where I start it and adjust it to around 1300 then let it run (with the clutch depressed) for several minutes when really cold. The sooner you can get the oil flowing to all four corners of your engine the better. 1500 or more sounds like it's racing to me and I think the engine oil will reach the pressure limiter so any faster will not do any good.

Shutting an engine off at well above idle speed is actually hard on a number of parts....not really a good thing to do. It's really bad on engines with timing belts, almost as bad for those with timing chains, and least bad on those with timing gears (like your engine), but it still loads pretty much everything that spins (cam, crank, rods, etc) in the "wrong" direction. It may never cause a problem you see, but it's one of those things that's easy to avoid, just in case. Some engines are built with those loads in mind (think engine braking on big rig diesels), but I don't believe that's typical of tractor engines.

If you want to start at that throttle setting, you could just make a mark that you could line up with the throttle, and be at your chosen RPM.

 

[GManBart]

Cold engines do not start hard because of poor combustion. Cold temperatures cause the viscosity of the fuel to become heavier. Thicker, fuel atomizes less efficiently, making the engine more difficult to start. Opening the throttle enriches the mixture of atomized fuel to air. When the amount of atomized fuel is high enough, there is combustion, irregardless of the temperature.

Well since everybody is correcting everybody else, I guess we shouldn't let mistakes like this go unaddressed.

There is combustion regardless of temperature? The ONLY reason combustion happens in a diesel is because the proper temperature has been reached due to compression. It doesn't matter how much atomized fuel is present, you won't get combustion without the proper temperature being achieved.

FYI, "irregardless" isn't a proper word, it's the illegitimate child of "regardless" and "irrespective". Lots of people use it, and all of them are wrong.

 

[RoyJackson]

Shutting an engine off at well above idle speed is actually hard on a number of parts....not really a good thing to do.

I agree and I lower the RPM smoothly to the minimum throttle setting...give it a second or three, then shut the engine down.
On a related note, always engage and disengage the PTO at low RPM. Before disengaging the PTO, I'll let it run at low RPM for a short period of time (30 seconds or so). It's a bit easier on the PTO brake and implement.

 

[mikehaugen]

Well since everybody is correcting everybody else, I guess we shouldn't let mistakes like this go unaddressed.

FYI, "irregardless" isn't a proper word, it's the illegitimate child of "regardless" and "irrespective". Lots of people use it, and all of them are wrong.

I'm glad I'm not the only one.

 

[CobyRupert]

Do you think cold transmission oil would act like a sticking brake?

 

[vtsnowedin]

Do you think cold transmission oil would act like a sticking brake?

I say yes. When it is -15F it is like molasses and is hard for the gears or pumps to stir. The heat from the engine will move back through the outside castings and driveline parts so the effect will not last long once the engine is warm and you are moving. Just driving ahead will stir the oil and add energy as heat to it plus running through the power steering pump warms it up.
So letç—´ see where the discussion has gone. I get from it that to reduce wear and tare you should plug in your tractor before a cold start if you can and once started should let it warm up at about 1200 to 1300 RPM to generate enough heat to warm up all the parts. Then you should start out slow and easy until the transmission fluid has warmed up by convection from the engine and friction running through the pumps. After you are done using the tractor you should bring it to an idle as slow as it will go to let the turbo cool down for a minute or two then shut it down while on low idle to not have any backlash stress parts on shutdown. Then plug it back in so it's ready for the next cold start.
What have I missed or gotten wrong?

 

[ray66v]

Well since everybody is correcting everybody else, I guess we shouldn't let mistakes like this go unaddressed.

There is combustion regardless of temperature? The ONLY reason combustion happens in a diesel is because the proper temperature has been reached due to compression. It doesn't matter how much atomized fuel is present, you won't get combustion without the proper temperature being achieved.

FYI, "irregardless" isn't a proper word, it's the illegitimate child of "regardless" and "irrespective". Lots of people use it, and all of them are wrong.

1. Sorry, that I did not write a book to make that clear enough for you to understand. The temperature I was referring to was, "ambient temperature". (That would be the temperature of the air in the surrounding area.) The hint was, the discussion was about cold weather starting.

2. When you have cleaned up the egregious mistakes in spelling, grammar, and words that do not exist as seen daily on here, come back, and you can talk about knit picking my grammar. :laughing:

 

[CobyRupert]

So when its cold out, the heat from the compression sinks into the piston, head, sleeves, etc... and doesn't reach auto-ignition temp, whereas a gas has the plug to spark it?

 

[RoyJackson]

So when its cold out, the heat from the compression sinks into the piston, head, sleeves, etc... and doesn't reach auto-ignition temp, whereas a gas has the plug to spark it?

That's about it...a gas engine is spark ignition...a diesel is compression ignition. The diesel has turn be turning fast enough and the combustion chamber has to hot enough.

 

[RoyJackson]

Do you think cold transmission oil would act like a sticking brake?

I say yes. When it is -15F it is like molasses and is hard for the gears or pumps to stir. The heat from the engine will move back through the outside castings and drive line parts so the effect will not last long once the engine is warm and you are moving. Just driving ahead will stir the oil and add energy as heat to it plus running through the power steering pump warms it up.
So letç—´ see where the discussion has gone. I get from it that to reduce wear and tear you should plug in your tractor before a cold start if you can and once started should let it warm up at about 1200 to 1300 RPM to generate enough heat to warm up all the parts. Then you should start out slow and easy until the transmission fluid has warmed up by convection from the engine and friction running through the pumps. After you are done using the tractor you should bring it to an idle as slow as it will go to let the turbo cool down for a minute or two then shut it down while on low idle to not have any backlash stress parts on shutdown. Then plug it back in so it's ready for the next cold start.
What have I missed or gotten wrong?

You've pretty much nailed it, Warren
I don't plug it back in unless I'm going to let it set for more then an hour outside...