M7040 glowplugs

[jcummins]

I bought a used 2007 Kubota M7040 3 months ago....like it a lot. It is the 2nd M7040 I've had. The first one, a 2008 model I bought new in Texas.

I have a unheated but insulated barn I keep the tractor in. With this cold weather, finding the tractor turning over cold really slow. I hooked another battery in series, it did help, but I don't really think this is a bad battery issue. The 08 I never experienced that...but being in Texas then, never got this cold either.

Glowplugs...on this model I've read they come on very briefly if at all. First...I wonder why so brief. Every other diesel I have, the glowplugs are on for awhile in the cold before start. I have yet to see the glowplugs come on. Temp in the barn is about 35, and have read they don't come on until it's 32. I do wonder why.

BUT...I wanted to check them, tried to locate, and I can't even find glowplugs on the motor. Anyone with M7040 have a picture of them? And...what's the opinion of a hose heater in the lower radiator hose. Thinking I may add, but want to figure out the glowplug issue first.

 

[Tx Jim]

GP's are parts key #100. Electrically besides ign switch there's a timer & relay that controls the GP's.

 

[jcummins]

That scheme shows why I couldn't see them. With the loader on....tough to view things on recesses on top of the motor. I doubt there is an actually issue with the plugs themselves, but in regard to how controlled...another matter.

I have a JD Gator, and I haven't timed it, but the glowplugs come on even in the summer, and in this temp....on for 6-10 secs. I have a Duramax, in this temp, they come on for quite a little bit. Tractor sitting right beside the Duramax in the barn...not even a blip.

BUT, having said that, is this a design issue, since I've read that others with the M7040 almost never see them come on, and if they do, better be quick looking cause they ain't on long. This seems completely foreign to the diesels I've used. Is it true they only come on if it gets to 32 degrees?....it's about 35 in the barn. If they are designed that way, can the timer/relay/controls be altered so they come on earlier? This tractor once warmed up in this temperature, starts with one turn of the motor, almost immed, so it seems glowplugs aiding in starting would be desirable.

 

[bigbull338]

today is the 1st day weve goten out of the 30s for highs in 8 or 9 days.we got up to 41,an my tractor cranks fine with the glow plugs.so you could a weak battery ot glow plugs or both.

 

[wmonroe]

Try testing the glow plugs to make sure they are good, if I remember right from another thread they should register about .6 ohms of resistance.

 

[the8080]

Maybe I"m missing something, but it looks like the manual in the other thread says the glow plugs only come on if you use the preheat position on the ignition. Manual says 2006. Don't know if 2007 is different.

 

[jcummins]

Maybe I"m missing something, but it looks like the manual in the other thread says the glow plugs only come on if you use the preheat position on the ignition. Manual says 2006. Don't know if 2007 is different.

I just come across that myself. Wasn't aware of a preheat position....haven't ever 'felt' any difference in the key from on to start. The only positions I was aware of is off/on/start. Not sure how I know to be sure the key is in the preheat position. Tomorrow I need to look closer at that.

 

[the8080]

Until someone comes up with the real answer, two things to try. 1. Some tractors had preheat at a spring loaded position backwards from ON. Turn key CCW. 2. The electrical diagram and write up in the manual makes it look like there is a nondetent position between ON and START that is preheat.

 

[Tx Jim]

I'll quote what my '11 M7040 OM states about cold weather starting. Turn key to "ON" position and leave it there until glow plug indicator on dash turns off. Proceed to start engine by turning key to start position
Glow plug indicator comes on when the key is turned to "ON" position and engine coolant temp.is below O degrees C(32 degrees F) and goes off automatically when preheat is completed.

 

[jcummins]

I'll quote what my '11 M7040 OM states about cold weather starting. Turn key to "ON" position and leave it there until glow plug indicator on dash turns off. Proceed to start engine by turning key to start position
Glow plug indicator comes on when the key is turned to "ON" position and engine coolant temp.is below O degrees C(32 degrees F) and goes off automatically when preheat is completed.

Yes Jim...I read that. This morning 5 degrees outside. My unheated barn is insulated and does a good job, but got to believe it was 32 or below in there. My not so good thermometer said 32, need to get a different one. The problem I have with that....I think the glowplugs should come on with temperatures 50 or below, if ever so briefly. I tried to turn the key ever so slowly this morning to put the switch into the glowplug cycle before the start....it did not blip. The tractor did start, but it turn over extremely slowly....rumph.....rumph......rumph...........rumph.....started. Every time I've checked the battery, it sits at 12.6 to 12.7 volts. I don't have a way of load testing the battery. It's a Duralast with a 06/11 sticker on the side, so 2 1/2 years old. After warmed up, a restart is immed, one turn over of the motor.

I see the glowplug fuse, but getting to it is another matter. Almost have to take the loader off. Not sure of my next action on this.

 

[Tx Jim]

I would use a volt/ohm meter or test light and turn ign switch to on then see if there's any electricity to GP's. Problem could be fuse or relay.

 

[suzy]

Today was just hovering around the -2 or -1C, so didn't have my m7040 plugged in. With the key turned to the glowplug position, the green glowplug light came on for two or three seconds, then went out. Started right up. Came in at lunch time, now at 0C. An hour later, no glow plug light, but was probably still warm from the morning.

 

[jcummins]

Today was just hovering around the -2 or -1C, so didn't have my m7040 plugged in. With the key turned to the glowplug position, the green glowplug light came on for two or three seconds, then went out. Started right up. Came in at lunch time, now at 0C. An hour later, no glow plug light, but was probably still warm from the morning.

What year is your 7040...and is there positions with the key that are detents (stopping points) for off/on/glowplug/start? I sthe glowplug position between on and start?

I pulled the loader up high so I can better get under the hood today....but it's cold enough here I don't want to spend a lot of time in the cold. It was 5 degrees Fahrenheit this morning.

 

[jcummins]

Next week it suppose to get a bit warmer during the day....40s. Have an easier time working with it.

What controls the temperature that the plugs come on....the relay? I think I see the fuse, but where is the relay located
I'm wonder if the bulb may be burned out too. How do you get to it? Does the whole cowling have to come off? If it was nice and warm I'd be taking things apart, but prefer to not open up things unless I have to.

 

[wmonroe]

If the engine is cranking over slowly then you might have a separate issue, are the battery terminals clean? What about the cable connection at the starter? Is the battery the correct CCA?

 

[big bubba]

"Glow plug indicator comes on when the key is turned to "ON" position and engine coolant temp.is below O degrees C(32 degrees F) and goes off automatically when preheat is completed." tx jimmp

if operating correctly, the glow plugs will be indicated on dash (amber light) if coolant is below certain temp (32 degrees?). the length they remain on is according to how much below that temp. so if you say it's 5 degrees, will stay on longer than 32. if the engine turns slowly in that case, of course it could be the battery as you say, but also dependent on viscosity of engine oil. if it's 15/40, guarantee the engine will turn slowly @ 5 degrees. a lower rated viscosity range (ie 5/40 syn diesel rated) will turn over considerably easier. what grade oil do you have in it? good luck

 

[jcummins]

I've got Rotella 15w40 in it....and that has crossed my mine. Rotella makes a 5w40, I just may go to that given this issue. I've used the same 15w40 year round in my Duramax with 230K miles with zero issues and that's why I used it.

The battery seems good ..... but it may be the reserve in the battery. It is 700cca. I always oversize my batteries, and would prefer a 900cca. I do not know the spec the tractor calls for, and my manual is in the cold barn right now.

The point that no one has answered, is what is magical about the glowplugs coming on at 32 degrees, and what specially controls that? ALL and every other diesel I've had the glow plugs come on MUCH sooner than that.

 

[big bubba]

feel as though the slow cranking is oil related. esp @ 5 degrees. not familiar w/schematic, but there's a coolant sensor that triggers the plugs for however long. but you never said how how easily it starts aside from sluggish cranking, any problem? the glow plugs are doing their job. if you intend to regularly use it in these conditions, would opt for T6 if you want to stay w/rotella. (what i use)

 

[jcummins]

feel as though the slow cranking is oil related. esp @ 5 degrees. not familiar w/schematic, but there's a coolant sensor that triggers the plugs for however long. but you never said how how easily it starts aside from sluggish cranking, any problem? the glow plugs are doing their job. if you intend to regularly use it in these conditions, would opt for T6 if you want to stay w/rotella. (what i use)

If it was truely 5 degrees...yes I would agree. It was 5 outside but in the unheated but insulated barn, think it was more like low 30s. The Gator and the Duramax sitting right next to the tractor does not crank like that.

If the glowplugs are working...then the light in the dash is bad, since it does not come on. Outside of the sluggish crank, the tractor does fire right up.

Perhaps I need to go to the trouble of taking the battery out and have it load tested....but I really don't think that is the problem.

 

[wmonroe]

Since the tractor is cranking slow while your truck and gator are not is what make me think you may have a battery or connection problem. There might still be an issue with the glow plugs not coming on but if the tractor is starting ok then maybe it just isn't cold enough.