Cold starts: what is your preferred RPM setting??

MapleLeafFarmer

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Equipment
Lots incl. B and L kubotas
Dec 2, 2019
219
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E.
when very cold I like to let my glow plug (combustion heaters) cycle for 30 - 60 seconds before I hit start more than just when the light goes out.

always wondered though at what rpm level other people set their throttle at (rpm level) when they cold start? I am usually set at 1,400 rpm or a little lower when the tractors first start up in cold weather.

I also use block/oil heaters so not true dead cold starts.

wonder what others are doing?
 
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85Hokie

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BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
Jul 13, 2013
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On my BX's - I glow and start at the idle throttle setting. On my B7100's I open the throttle about 1/3 or so to start after glowing for a bit longer than a BX
 

fried1765

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Kubota L48 TLB, Ford 1920 FEL, Ford 8N, SCAG Liberty Z, Gravely Pro.
Nov 14, 2019
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Eastham, Ma
when very cold I like to let my glow plug (combustion heaters) cycle for 30 - 60 seconds before I hit start more than just when the light goes out.

always wondered though at what rpm level other people set their throttle at (rpm level) when they cold start? I am usually set at 1,400 rpm or a little lower when the tractors first start up in cold weather.

I also use block/oil heaters so not true dead cold starts.

wonder what others are doing?
"When very cold"....... I do not use my glow plugs at all!

L48 TLB is in unheated barn as of mid November.
I am in Florida, until May 1st!
 
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GeoHorn

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M4700DT, LA1002FEL, Ferguson5-8B Compactor-Roller, 10KDumpTrailer, RTV-X900
May 18, 2018
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Makes no difference…summer or winter….I start it at Idle (800-1000 rpm) and let it stay there until oil pressure is stable for 1 minute…then…depending on if it’s summer or winter (warm or cold)….I run it up to 1400-1500 in summer and go to work…. or let it run (winter) there (1400-1500) for another minute or so…and then go to work.

My tractor lives in an insulated metal bldg…usually unheated unless the temp is below freezing.
 
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Danno1972

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MX5100
Nov 19, 2022
3
0
1
Alberta, Canada
when very cold I like to let my glow plug (combustion heaters) cycle for 30 - 60 seconds before I hit start more than just when the light goes out.

always wondered though at what rpm level other people set their throttle at (rpm level) when they cold start? I am usually set at 1,400 rpm or a little lower when the tractors first start up in cold weather.

I also use block/oil heaters so not true dead cold starts.

wonder what others are doing?
The light goes out? I never waited that long before ;)
 

jimh406

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Kubota L2501 with R4 tires
Jan 29, 2021
1,366
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Western MT
I don't know how cold you are talking about. I use the block heater in Winter. I don't usually use the tractor much below 20. We don't usually have much snow when it gets below that temp. I use my glow plugs per the manual and keep throttle at lowest setting. I have an L2501 HST. I also use Power Service Winter fuel additive.

Screenshot 2022-11-19 at 2.41.01 PM.png
 
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DustyRusty

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BX23S
Nov 8, 2015
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I start my BX at idle and since I have a block heater in use during the winter when necessary, my tractor is ready to go within a minutes of my getting onto it. Did that with my old BX and it never suffered any harm. The first pass of the snowblower is at just above idle, and then I bring it up to full power to do the rest of the snow blowing. This is what the Kubota dealer told me 20 years ago, saying that diesels work best at full throttle and not to lug the engine at low RPM.
 

MapleLeafFarmer

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Lots incl. B and L kubotas
Dec 2, 2019
219
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43
E.
I don't know how cold you are talking about. I use the block heater in Winter. I don't usually use the tractor much below 20. We don't usually have much snow when it gets below that temp. I use my glow plugs per the manual and keep throttle at lowest setting. I have an L2501 HST. I also use Power Service Winter fuel additive.

View attachment 90890
thanks.... I put on more hours when colder than -20F than hours above 50f.

unfortunately the pre-heat tables in the manual do not go to the temps we get around here during snow blowing season. Regardless I give my glow plugs lots of time to make their work. Probably more time than most I am guessing. I don't rush them.

In my case when winter cold is here (no I don't mean Texas or Florida winter cold but Canada / Minnesota cold) starting with throttle pulled all the way back to min. means I have to hit my starter probably more than once maybe 2 or 3 times but when started at throttle set at 1,400rpm or a little lower it starts up first hit of the starter.

The new Kubotas seem to me to be very very good at starting when very cold.

cheers

So for me a little bit of throttle over min. seems to make starting easier. Was wondering how other cold users do it.
 
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GeoHorn

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M4700DT, LA1002FEL, Ferguson5-8B Compactor-Roller, 10KDumpTrailer, RTV-X900
May 18, 2018
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Texas
My 1996-era M4700 automatically energizes the glow-plugs when “start” is selected regardless of temperature. There is a “manual” method of heating them by turning the key-switch to that position for the prescribed amount of time…but I’ve noticed that on below-freezing days…if I use manual glow-plug heat the engine starts on the second compression-stroke (my imagination here) while if I do not use the manual and instead let it do the “automatic” thing…. it takes about 4 revolutions and it fires right-up.
Just FYI.

(I think it’s nicer to get it fired up in as few revolutions as necessary in order to be kind to the starter.)
 
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Jchonline

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Kubota L6060, KX040-4, M7060, RTV X1100C, M62 (sold)
Oct 28, 2018
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Red Feather Lakes, CO
when very cold I like to let my glow plug (combustion heaters) cycle for 30 - 60 seconds before I hit start more than just when the light goes out.

always wondered though at what rpm level other people set their throttle at (rpm level) when they cold start? I am usually set at 1,400 rpm or a little lower when the tractors first start up in cold weather.

I also use block/oil heaters so not true dead cold starts.

wonder what others are doing?
Glow on the L60 is automatic. Turn the key let the glow go out then start. Never had an issue with any of my last 2 Kubotas doing this . I let it idle to warm. I also use block heater when its less than 15 out. I do have battery maintainer on it during the winter as well. We hit -7 night before last.
 
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nbryan

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B2650 BH77 LA534 54" ssqa Forks B2782B BB1560 Woods M5-4 MaxxHaul 50039
Jan 3, 2019
897
480
63
Hadashville, Manitoba, Canada
In cold weather season, when parking the tractor after usage to shut it down, I set my idle a bit higher than low idle - usually 1250 - 1300rpm, then shut it off.

Then after it cools off, maybe the next day, it will be preset at a good start and warmup idle rpm. 5 - 10 seconds of glow, depending on temperature, and fires right away when cranked.
 
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Daferris

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LX2610
Nov 23, 2021
234
191
43
Mid-Michigan
I store my LX2610 in a unheated barn. But I have a block heater that I have connected to a Wi-Fi controlled outlet. I run the block heater for 45min to and hour before I go out to start it. seldom is it below 0F in the barn (Mid-Michigan) It starts right up with just a few seconds of glow plug preheating.
As to the RPM I keep it a a slow idle for about a minute then run it up to 15-1600 RPM till it starts to register an increase in water temp then I plow with it running at 1900-2000 RPM.
I try not to start it or the truck in the winter without running the block heater. It will start with out them but it's just easier on the motors for them to wait till some heat in them before starting them.
 
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Captain13

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M7040 4WD ROPS, ZD28, Woods (84” box blade, 72” harrow, 48” pallet forks)
Feb 27, 2019
432
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Kathleen, GA
I crank and go to 1000 for a couple of minutes, then increase to 1400 for another three. On really cold days, I will put the tractor in first gear (low) and idle out of the barn for a couple of minutes more and then go to work. my main concern is warming up the hydraulic oil.
 

lynnmor

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B2601-1
May 3, 2021
824
573
93
Red Lion
I try not to start it or the truck in the winter without running the block heater. It will start with out them but it's just easier on the motors for them to wait till some heat in them before starting them.
I frequent a truck forum and see that so many think that a block heater is only about getting it started. Others think that it is for their personal comfort by getting quicker heat to the cab. A block heater is for the good of the engine and using it as you described is the correct plan.
 

Biker1mike

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B6200, Kubota 2030 Front Blade, King Cutter 60" finishing deck
Jan 11, 2022
561
463
63
Gallatin, NY USA
Older and smaller engine.
Below 20 F. 60 seconds of glow plugs. Throttle to half. Pull compression release and turn to start. If the engine turns but does not start within a few seconds this is repeated with another 30 seconds of glow plug.
Once the black exhaust stops ( 2-5 seconds or so) I throttle back to 14-1500. Idle for a couple of minutes and move plow up/down/left right to get fluid flowing. Back throttle down to just above where the alternator light blinks.
Slow and steady from shed to main driveway. Then foot throttle. I am not gentle when I plow snow so rpm will bounce from near idle to wide open for the next hour or so. When done I will let tractor sit at just above idle for a few minutes before I back it in to the shed.
 

ItBmine

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B2620, RTV-X1100C
Jan 21, 2014
1,245
257
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Canada
It averages minus 25 degree Celcius in winter here and goes down to minus 40 in January and Feb.

My B and RTV are in unheated buildings. I never have to glow plug for more than 4 or 5 seconds and I start at idle. I let idle until oil pressure steadies, then just bump them up slightly and let them warm up 15 to 20 minutes before I use.

When it is colder than minus 25 I will plug the block heaters in juts to make it easier on them.
 

ItBmine

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B2620, RTV-X1100C
Jan 21, 2014
1,245
257
83
Canada
I've been a trucker and heavy equipment operator all my life so I still have that old school way of thinking. I can't do what the Kubota manuals say and start them at half throttle. That makes me cringe.
 
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nbryan

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B2650 BH77 LA534 54" ssqa Forks B2782B BB1560 Woods M5-4 MaxxHaul 50039
Jan 3, 2019
897
480
63
Hadashville, Manitoba, Canada
I've been a trucker and heavy equipment operator all my life so I still have that old school way of thinking. I can't do what the Kubota manuals say and start them at half throttle. That makes me cringe.
i took the "1/2 throttle" as "half RPM" so set my start idle around 1250 which is half of the operating RPM for my tractor, which is 2500rpm.
 

netsomnia

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L2501 tractor, with BB1260 box blade, LA525 loader, and RCF2060 cutter
Jan 30, 2022
6
1
3
Missouri
I did my first cold start on my '22 Kubota L2501 today. I didn't like it and I will be using the block heater always from now on. Unfortunately where the machine shed is I had to use a power inverter for AC and it was drained before I had a chance to start the tractor. I hope my significant other reads this too. :)
 

The Evil Twin

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Equipment
L2501
Jul 19, 2022
531
375
63
Virginia
I just follow the manual. Roughly 1200 rpm and leave it there for a minute or two. Then I'll pull it out of the shop and roll at that same rpm.
You want to get the oil pump moving and some heat in the engine. Starting and "warming up" at idle isn't going to do it as well. My last two trucks would stay on high idle for a minute or three when it's super cold. That's all programmed from the factory. I can't imagine they would do it if starting them with increased idle speed was bad.