Maybe we should have gotten a crankcase heater in the L3940!

   / Maybe we should have gotten a crankcase heater in the L3940! #1  

Grateful11

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Our L3940 is used everyday for feeding 50 head of cattle or doing something else. It's kept in an unheated insulated steel building but even with temps in the 30's outside it's having some difficulty starting. It hasn't failed to start yet but it's pretty darn sluggish at turning over. It's run long enough everyday to bring the coolant temp into the normal range, I'd say it's run at least 15 minutes everyday. Today we never shut it off while using it so I'd say it ran a good 30 minutes air temps in the 30's. My wife does the majority of the driving and she always waits for the glow plugs to click before trying to start it. Is a crankcase heater user installable? Are we running it enough each day? Is this normal or could we have a charging problem? Do we need to run a lighter weight oil than the 15W40 we run in all our tractors except the gas antiques.
 
   / Maybe we should have gotten a crankcase heater in the L3940! #2  
I have a L2900 and it starts great in even colder weather.I do have 5w30 oil in for the winter and I have a battery tender on all of the time and it starts quick.I would check your battery it may be weak.
 
   / Maybe we should have gotten a crankcase heater in the L3940! #3  
Save your money and buy a propane or kerosene fired

salamander and in twenty minutes it will be up to

near operating temperature no matter the weather.
 
   / Maybe we should have gotten a crankcase heater in the L3940! #4  
Blockheater or inline heater would make starting easier. Battery tender is also a good idea for the short run times you have.:)

Every so often work it hard for a while to clean up the oil condensation.:)
 
   / Maybe we should have gotten a crankcase heater in the L3940! #5  
Your tractor has a curable problem if it starts hard above freezing. That is simply not normal.
 
   / Maybe we should have gotten a crankcase heater in the L3940! #6  
The coldest we got last winter was 0F actual (windchill not included). I went out to our un-insulated un-heated barn just to see if the new Kubota L3940 would start. No heater aids, just factory glow plugs. The tractor started just fine, sure, it knocked and smoked for the first 15 seconds, but it was 0F that morning! I use synthetic 5w-40 year round, Power Service in the white bottle year round, and diesel from the local truck stop. I make sure to have the winter blend in the tank this time of year. Good luck. Philip.
 
   / Maybe we should have gotten a crankcase heater in the L3940! #7  
The block heater is user installable with about an hour's work. The thing about those is that you want to plug it in about 30-40 minutes before you start the machine. It will make starts easier. Once I started my tractor at -15F just to see if it would get going. It did, but it sounded terrible and pushed out white smoke for half a minute or so. That was the one and only time I did that. I plug in the block heater for about 45min - 1hr when the temp is above 10F and for 1.5 hrs when it is 0F or colder. The engine start as easy as in the Summer.
In my mind 15 minutes is barely enough for the machine to reach proper operating temperature.
 
   / Maybe we should have gotten a crankcase heater in the L3940! #8  
I've got my L3540 rigged with a block heater AND battery blanket - I plug it in for 1 or 2 hours before I start it and when I do it already has 1 bar on the temp gauge. If you are using it everyday get a timer that turns on the block heater automatically ever day. With 1 bar on the gauge I usually let it run for another minute or two to get the oil flowing and go.

I would also recommend changing to a winter grade grease.........
 
   / Maybe we should have gotten a crankcase heater in the L3940! #9  
I just started mine,been outdoors at 15-20 degrees for a week,check your fuel,use an additive,or your battery might be low.I have started mine at 0 degees with-out plugging in just to try,starts fine.Block heater helps to warm the oils and easier on the motor.May need to change oil viscosity also.
Mine is a L4240 HStc/
 
   / Maybe we should have gotten a crankcase heater in the L3940! #10  
I wonder if your run time is enough to keep the battery charged. If you have a volt meter, check the battery voltage before starting and see what you have. I believe 12.6+ volts is a fully charged condition, 12.4=75%, 12.2=50%. An engine with glow plugs should not have any problem starting at 30˚ provided the battery is charged enough to spin the engine over good. You might need to put the battery charger on it once a week or more to keep it charged. A block heater is a good thing too. If you feed at a given time each day, just put it on a timer. That would save your battery too with quick starts.

Kim
 
   / Maybe we should have gotten a crankcase heater in the L3940! #11  
What are you using for diesel fuel? Are you waiting until the glow plug light goes out? Does it have any antigel in it?

Since the fuel I got last spring was questionable as to if it had anything in it I put the last of the CRC antigel into my 4240. My garage is uninsulated and I have started it easily at temps in the low 20s. I did get a block heater dealer installed but I haven't even looked for the plug yet. Like Phillip said, a little smoke and knock for a few seconds then clears right up. I bet I haven't had to turn it over for more than 5 to 10 seconds before it fires up.
 
   / Maybe we should have gotten a crankcase heater in the L3940! #12  
I think KWentling called it right. At low temps, your battery output is already reduced, then you fire up with glow plugs and thick oil, takes a lot of amps to start it. Only running 15 minutes, unless you're running at near wide open throttle, the alternator possibly just can't put enough amps back in the battery.

pause...sorry but albert King and SRV are on PBS in a tape of them recording texas Flood together. Amazing... sure do miss that man.
 
   / Maybe we should have gotten a crankcase heater in the L3940! #13  
(1)With your short run time, my vote is for the battery tender plus which is temperature compensated. Battery Tender - Home of the Battery Tender Jr. - Batterytender.com

The Jr or other fully auto tenders are fine and will save you some money but IMHO the 'plus' is the best.

(2)Consider going to full synthetic. I now use it in the tractor , my generator and my diesel pickup which all need to start in the coldest of times.

Make sure you don't have a voltage leak either from the Kubota or via something you may have added to it.

My Kubota arrived in the spring of 05 and is still on it's original battery at 550hrs. I am waiting for my first battery tender to arrive, as I realize I am pushing my luck with this battery. I also just put synthetic in the tractor for the first time also.

I have the block heater but only use it on extreme cold days when I remember to do so and don't leave the tractor too far from an outlet. The tractor has always started regardless of being as much as below -30F without the block heater. The tractor is kept outside 365. I usually run it for well over an hour in the winter (plowing).....

Good luck
 
   / Maybe we should have gotten a crankcase heater in the L3940! #14  
I've also seen it suggested elsewhere to keep the glow plugs burning for a few seconds even after the engine starts.
I've tried this a few times and it does seem to rid the rough running a little quicker than just letting the glow plugs go out as soon as the engine starts. Not that it will help the issue with slow turning over in cold weather, but it will smooth the motor out just a tad quicker after a cold weather start.
 
   / Maybe we should have gotten a crankcase heater in the L3940! #15  
I've also seen it suggested elsewhere to keep the glow plugs burning for a few seconds even after the engine starts.
QUOTE]

That is not an option on the Grand Lxx40 series. The glow plugs are on a start timer activated by the key. You could cycle the key 2 or 3 times before you attemp to start. Electronic engines like the Cat C7 and Cummins QSB6.7 do this with their grid heaters, but it is part of the ECU programming. After start, they will energize the grid heater while the engine is in cold start mode. One thing I noticed on my L3940, at engine idle, the alternator is not charging the battery. The rpm's need to be at 1200 for the alternator to start charging. In winter time, I start tractor, let idle for a couple minutes, then increase rpm to 1200 and let it finish warming up. Philip.
 
   / Maybe we should have gotten a crankcase heater in the L3940! #16  
I would second earlier suggestion about battery tender...it sounds like you have easy access to electricity, so it is the quickest, easiest thing to try first...install permanently and plug it in every time. If it works, you've found a problem and a solution.

If it works you might suspect the battery, which can be tested ...if you run a big electrical load you might want to swap out for a larger alternator.

Other quick fix is oil change to winter synthetic. If that makes a big improvement, chances are you are never letting engine run at operating temp for long periods ...water condenses in oil, never is boiled out and makes the oil mushy at below freezing temps ...if short trips are the nature of your use, consider shortening the time between oil changes. Of course, block heater would improve things and is probably a good investment, but even so, I would install battery tender.

Slow cranking is either battery/charging-system, starter, and/or viscous oil
 
   / Maybe we should have gotten a crankcase heater in the L3940! #17  
I certainly agree with most of the posts. Battery blanket makes all the difference in the world although you might question the battery itself. In our region we get about 4 to 5 years out of a battery, then the reserve seems not to be there.

Block heaters are pretty standard in Canada. In cars they are generally recommended when it reaches about 10F. In my 3940 (my first winter with it), I've been plugging in for at least 2 hours once the temperature is below 20.

I have cycled the glow plugs a few times if it is below 30, it seems to start better. I presume the glow plug is smart enough to know when the cylinders are too warm.

My last tractor I used a synthetic 0W30 motor oil. I've gone back to the recommended oils only, I've concluded the motor is too expensive to screwup.

The circulating block heater is very easy to install - we used it in the last tractor. If you have a cab the heater will be warm immdeiately.

Garth
 
   / Maybe we should have gotten a crankcase heater in the L3940!
  • Thread Starter
#18  
Well I'm still trying to digest all this. Today only made it to 31 degrees but I looked at the thermometer in the equipment shed and it was on 48, this at 2 pm. It's still turning over pretty sluggish. I might video it starting tomorrow. I'm thinking it's probably the run time. In the spring and summer she always turns it off at least twice while feeding and it's probably taking a toll on the battery. This is her second winter feeding round bales, last year she used the 574 which doesn't have glow plugs or ether and she didn't have much of a problem. On the days that got down around 10 she really had to play with that weird start/run/stop lever thing it has. I have a good volt meter and I'm going to take some readings. If the alternator isn't up to snuff I'll call the dealer and see what he says.

BTW: She's definitely waiting for the glow plug light to go out, I made sure of that. She's pretty efficient at operating all this stuff, she's been on and around farm equipment for over 40 years.
 
   / Maybe we should have gotten a crankcase heater in the L3940! #19  
Well I'm still trying to digest all this. Today only made it to 31 degrees but I looked at the thermometer in the equipment shed and it was on 48, this at 2 pm. It's still turning over pretty sluggish. I might video it starting tomorrow. I'm thinking it's probably the run time. In the spring and summer she always turns it off at least twice while feeding and it's probably taking a toll on the battery. This is her second winter feeding round bales, last year she used the 574 which doesn't have glow plugs or ether and she didn't have much of a problem. On the days that got down around 10 she really had to play with that weird start/run/stop lever thing it has. I have a good volt meter and I'm going to take some readings. If the alternator isn't up to snuff I'll call the dealer and see what he says.

BTW: She's definitely waiting for the glow plug light to go out, I made sure of that. She's pretty efficient at operating all this stuff, she's been on and around farm equipment for over 40 years.


You do know that a diesel engine is huge HEAT SINK dont you?

If your alternator belt is loose thats most if not all your problem;

If it has more than an eighth of an inch of slop................... and depending on the belts condition it may be bad and turning to powder due to the slop and excess wear further you dont need to shut it off while feeding just set it at idle and set the brakes.

The very second that the first cylinder that is in the firing order explodes its ration of fuel the rest wil follow simply due to the power generated by the first cylinders exploding the measure of fuel.

Check your alternator belt before anything else. Then remove the battery if the belt is tight, charge it overnight on a low charge rate, and then take it some where to have it tested with a load tester; It acts like you just might have a broken cell that makes contact and breaks contact.

A kerosene salamander is a diesel tractors best friend. twenty minutes after ignition the engine and cooling system will be near operating temperature, the engine oil will be warm and it will just purr when you start it.

( all that is needed is an heavy duty timer that the salamander is plugged into to heat the tractor and you will add years to its service life even in summer when its left overnight that engine is cold and the oil is cold so its behind the eight ball even in the warm months.





The problem with all internal combustion engines is simply one of no oil in the galleries when the engine is cranked and thats the biggest contributor to engine wear especially if the engine oil is cold.

several models of engine oil pumps are offered which pump the oil in the crankcase through the engine prior to ignition sequence.
 
   / Maybe we should have gotten a crankcase heater in the L3940! #20  
If it's 48 in your shed and it's turning over slowly you have a problem. I would check the belt like Leonz said. I would check the battery terminals make sure they are clean and tight. I would also check the line going to the starter. After that I would start it up and use a multimeter to measure the voltage across the battery. You should see somewhere near 15 volts.

If you are in need of a battery charger I have a Schumacher Speed Charge.
P1000385.jpg

This is a great charger and it will test your charging system. Then if nothing else I would call the dealer since any problem should be covered under warranty.
 

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