Starting Procedure

[bp fick]

The "feel" is pretty misleading on my 2660 and 5030 both. These things top out at a little over 3000, so half throttle or 1500 really isn't running it all that hard in my opinion. I really fail to see the reason for concern, but who knows.

Agree. With mine, the top is 3000-3200. Screaming. Realistic top end is 2900. It won't go lower than 1050, so starting/warming up at 1300-1350 is pretty much perfect. The band just isn't as wide as a car that can idle at 900 and go to 5500-6000. That half throttle thing is pretty much just what happens anyhow.

 

[KeithInSpace]

...half throttle or 1500 [RPM]...

...top is 3000-3200 [RPM]...won't go lower than 1050, so starting/warming up at 1300-1350 is pretty much perfect.

You aren't including that idle is ~1,000 RPM, so 1/2 throttle is ~2,000 RPM.

Starting/warming at 1,300 to 1,350 RPM represents approximately 15% throttle. Even 1,500 RPM represents 25% throttle.

That would be squarely in the "crack the throttle" camp.

Next time you fire up your machine, stone cold, run it straight up to 2,000 RPM and let it sit. I'd bet honest money that you couldn't stand it...you'd back it down to somewhere in the 1,300 to 1,500 range within 15 seconds. Cracked throttle.

That's my guess, anyway. Just wanted to honestly clarify what 1/2 throttle represents.

 

[Tractor Factor]

You aren't including that idle is ~1,000 RPM, so 1/2 throttle is ~2,000 RPM.

Next time you fire up your machine, stone cold, run it straight up to 2,000 RPM and let it sit. I'd bet honest money that you couldn't stand it...you'd back it down to somewhere in the 1,300 to 1,500 range within 15 seconds. Cracked throttle.

I think that's right, ~2,000 rpm...and that's what I did yesterday with the BX25, for the first time, after reading this thread. And you're right, after just 15-20 seconds I backed it down from 2,000 to maybe 1,500...just didn't sound or feel right.

Uh oh, guess I've become my dad.

 

[TripleR]

You aren't including that idle is ~1,000 RPM, so 1/2 throttle is ~2,000 RPM.

Starting/warming at 1,300 to 1,350 RPM represents approximately 15% throttle. Even 1,500 RPM represents 25% throttle.

That would be squarely in the "crack the throttle" camp.

Next time you fire up your machine, stone cold, run it straight up to 2,000 RPM and let it sit. I'd bet honest money that you couldn't stand it...you'd back it down to somewhere in the 1,300 to 1,500 range within 15 seconds. Cracked throttle.

That's my guess, anyway. Just wanted to honestly clarify what 1/2 throttle represents.

Good grief, I don't get that exact. I pull the throttle down to "about" half way and let it warm up. I can say that I NEVER let my BX idle; jars my darned teeth out and cracked the breather bracket on my BX2200.

I think I am missing something though, as my max RPM is about 3200, so how is 1500 not "about" half throttle.

If I want to experiment, I will have to take my glasses with me to see the tachometer

That is an interesting question though and I will try it the next time I start my BX or L up to see exactly "about" what my warm up is.

 

[poldies4]

You aren't including that idle is ~1,000 RPM, so 1/2 throttle is ~2,000 RPM.

Starting/warming at 1,300 to 1,350 RPM represents approximately 15% throttle. Even 1,500 RPM represents 25% throttle.

That would be squarely in the "crack the throttle" camp.

Next time you fire up your machine, stone cold, run it straight up to 2,000 RPM and let it sit. I'd bet honest money that you couldn't stand it...you'd back it down to somewhere in the 1,300 to 1,500 range within 15 seconds. Cracked throttle.

That's my guess, anyway. Just wanted to honestly clarify what 1/2 throttle represents.

Very good point for the sake of argument. Is it possible that the manual writers and the engineers got together and decided what half throttle actually means? Half throttle means just that, half of the pull on the stick. Otherwise I would assume that they would say half max rpm? On my BX half throttle is subjective as a spot, but I find that 2000-2200 rpm in the half throttle range. I agree with others that I could tolerate idling at that rpm for maybe 30 seconds, couldn't bear it. Is idle a bad thing? I let my tractor isle, at idle when I need to do something else for a minute. Never longer than a minute or two, but I gather from this thread that may not be so good?

 

[timswi]

Letting it idle won't hurt anything..It's better that restarting all the time. Again..By RTV1100 has the same engine as my BX...It defaults to idle.

 

[bp fick]

You aren't including that idle is ~1,000 RPM, so 1/2 throttle is ~2,000 RPM.

Starting/warming at 1,300 to 1,350 RPM represents approximately 15% throttle. Even 1,500 RPM represents 25% throttle.

That would be squarely in the "crack the throttle" camp.

Next time you fire up your machine, stone cold, run it straight up to 2,000 RPM and let it sit. I'd bet honest money that you couldn't stand it...you'd back it down to somewhere in the 1,300 to 1,500 range within 15 seconds. Cracked throttle.

That's my guess, anyway. Just wanted to honestly clarify what 1/2 throttle represents.

Interesting. If 2000 or 2100 rpm is what is defined as half throttle start up, you are correct. That isn't going to happen. I'll stick with my 1300 start/warm up, thank you.

If that shortens the life of my Kubota to "only" 3000 hours, then so be it. Given my age and at my present rate of usage, 60-80 hours a years, my kids will dealing with the issue and I will not care so much.

 

[KeithInSpace]

It would seem we're all doing the exact same thing...just have a little different way of looking at it.

For the sake of discussion, like Mr. Poldies4 my tractor idles quite a bit. Just circumstance, I guess. Usually have it at or just above idle when pulling trailers, picking up sticks, or getting dog poo with the FEL. Don't know why. Doesn't bother me much. And it hasn't complained yet either. I like the sound.

 

[ibnxe]

Ok, I'm back with the results of the chilled oil test. This test took a little longer than I thought it was going to. For this to be a real test I decided against pouring oil through a funnel as suggested. Instead I fabricated a test jig, consisting of an automotive oil pump scavenged from the junk bin. The pump has a 5/8" inlet and where the oil exits, I fabricated a cover plate/ reaction arm that I threaded with a 1/2" nipple. Attached to the nipple is a 1/2" id hose that dumps into a gallon jug. The pump was chucked up in a drill press, set to rotate at 650 RPM. The pump inlet pipe was placed into the test quart bottle of oil, to within a half an inch of the bottom of the quart bottle. The lift distance between the floor of the pump and the initial oil level in the bottle was about three inches. The test oil was Chevron Delo 15W-40. I placed two quarts in the freezer the other day and left two quarts on the workbench. At the time of the test, the cold oil was at 4 degrees F and the room temperature oil was at 65 degrees

Test procedure: Started drill press and stopwatch simultaneously. Clicked the stopwatch split button when I heard the drill press load down. Clicked the stop button when I heard the pump suck air. Between tests, I let the oil drain back out of the pump and suction tube.

Conclusions: The two room temperature samples took 0.8 seconds to draw the oil up the suction pipe, where the cold samples took 1.3 seconds.
The two room temperature samples took 32 seconds to transfer the quart of oil, where the cold samples took 34 seconds. The most noticeable difference being the increased load placed on the drill press motor, when pumping the cold samples.

I use 15W-40 year round, but the winter temperatures here are rarely below freezing. In colder climates, thinner oil would be preferred. Kubota's recommendation is a bit confusing, stating that a 10W-30 or 10W-40 can be used from temperatures above 77F to below 32F

When I start, I pull the throttle about half distance. I don't know the engine speed, for there is no tachometer. I would estimate it is between 1600 and 1800 RPM

I hope you find this informative. If nothing else, it should generate more discussion

 

[Dr. Bob]

I am impressed! There is nothing like some hard data to help people make a decision. I was suprised by the results. They also give me some comfort in not switching to 10W-40 in the winter.
Thanks for the using your "laboratory" to shed some light on this question.
By the way, my B7800 manual says "set the throttle lever to about 1/2 way." It says nothing about RPMs.