Glo Plug Cold weather

[Smokeless]

L 3901, 74 hours, purchased March

I am not sure glo plug working properly. Cold weather now, turn the key and glo plug indicator illuminates, goes off indicating ready to start, but the engine sure cranks slow, but starts.

Thought i would check battery, checks ok. Connections ok to.

I dont understand why the plug indicator does not stay on longer...similar to my 5.9 in cold weather.

Am i missing something or is my tractor functioning like all 3901.

Thanks, Butch

 

[mickeyd]

The engine cranking slowly has nothing to do with the glow plugs. If it starts, then the plugs are working properly.

What weight oil are you using?

If it is an HST, are you using SUDT2?

 

[North Idaho Wolfman]

If it real cold the only real fix is to install a block heater, that will cure the cold start blues!

 

[Smokeless]

The engine cranking slowly has nothing to do with the glow plugs. If it starts, then the plugs are working properly.

What weight oil are you using?

If it is an HST, are you using SUDT2?

Did not use SUDT2, 15-40W per head nod from dealer.

When I checked owners manual they recommended allot of weights including 15-40 down to 14 degrees, because most of my usage in is the hot summer months

Don't particularly have anything against synthetic.

thanks

 

[Smokeless]

If it real cold the only real fix is to install a block heater, that will cure the cold start blues!

Well, suppose to be fifty towards end of week, if the dealer has one believe I will install. Don't typically get bitter cold St Louis, but we can have some short periods of old man winter.

If not, I will turn on the torpedo heater and warm things a little.

thanks

 

[majorwager]

MX sleeps in unheated section of shop. T-6 synthetic in crankcase.

Temps in winter, teens to twenties F at nite. It is rare that tractor requires glow plug use to start. No block heater. Crank duration is very short, few seconds at most. Battery is from 2011 so a battery tender is active when tractor at rest.

Wish my other engines started this easily.

 

[North Idaho Wolfman]

Well, suppose to be fifty towards end of week, if the dealer has one believe I will install. Don't typically get bitter cold St Louis, but we can have some short periods of old man winter.

If not, I will turn on the torpedo heater and warm things a little.

thanks

Ok now 50f is not cold for these guys (50f is still summer weather here),Yes they are always going to start a little more sluggish that when it's 80 plus out but it shouldn't stop it from starting.
No need for a Block heater till the temps hit the 20f's or lower.
Have you done an oil change yet?, 5w15 will help with the cold starts.

 

[Smokeless]

MX sleeps in unheated section of shop. T-6 synthetic in crankcase.

Temps in winter, teens to twenties F at nite. It is rare that tractor requires glow plug use to start. No block heater. Crank duration is very short, few seconds at most. Battery is from 2011 so a battery tender is active when tractor at rest.

Wish my other engines started this easily.

Thats a great testimonial. My new 3901 has no option (as I can tell) to turn on glo plugs and hold for a few seconds. First turn of ignition turns systems on including glo plugs and they shut off pretty soon by some timer somewhere.

Mine has never failed to start, i was just a little taken back by how slow it turned over. Could be oil thick enough slow it down, just changed it at 49 hrs, sitting on 74 now.

Sounds like you have a good one

 

[85Hokie]

My BX will start after a very little glow....

My two B7100 (90-92) need a lot of loving with the glow plugs, even in warm weather.
Once warm - doesnt need it, but cold, needs a bout 10 seconds in warm and 20+ in cold - then it will belch a bit of smoke for 3 seconds and then smoke free.

Newer plugs must have a get red hot in a hurry mode!

 

[Smokeless]

Ok now 50f is not cold for these guys (50f is still summer weather here),Yes they are always going to start a little more sluggish that when it's 80 plus out but it shouldn't stop it from starting.
No need for a Block heater till the temps hit the 20f's or lower.
Have you done an oil change yet?, 5w15 will help with the cold starts.

Oil change at 49 hours, filter also. Installed 15-40 and dealer said thats fine, use finish mower on 3 acres.. I silently questioned that since winter approaching, but my manual does list 15-40 ok to 14°F. Seems mighty cold to me for that oil.

I dont my changing to lighter grade oil for the winter. We get allot temp variation in the midwest.

Thanks

 

[troverman]

My MX has automatic glow plugs like your L3901 and with temps in the 20's to 30's, they stay on maybe 5-7 seconds. But the tractor cranks over just as quickly as it did in the summer.

My tractor has 70 hours on it. The first service has not been done. I'm headed to the dealer later today to get the three filters.

Like many are saying, my dealer in NH pushes the 15W40. I think that's a great summer oil and not ideal in the winter. They do not even stock the 10w30 which I think is the other option. I've questioned them on this (two other Kubotas in my fleet) and they always say 15w40 is fine year round. I've noticed during winter starts the low oil pressure light stays lit longer with this oil.

I'm going to put 10w30 in mine for the winter. We say -22F last winter around New Year's.

 

[Smokeless]

My MX has automatic glow plugs like your L3901 and with temps in the 20's to 30's, they stay on maybe 5-7 seconds. But the tractor cranks over just as quickly as it did in summer

Temps 20s to 30s now. What got my attention was the engine did not turn over near as fast. Started but seemed
Like it struggle.

Yup, no manual operation to the glo plugs....full auto. I guess if i want to try and eliminate one critter i could change to a lighter weight oil and see what happens. We can get pretty cold weather here, so a block heater would help come Jan and Feb. Guess i will scratch head couple days and see

Thanks for posting

 

[SidecarFlip]

Did not use SUDT2, 15-40W per head nod from dealer.

When I checked owners manual they recommended allot of weights including 15-40 down to 14 degrees, because most of my usage in is the hot summer months

Don't particularly have anything against synthetic.

thanks

That is interesting. I do that with my HydroGear transmissions in my zero turn (because HydroGer recommends motor oil )but in an HST Kubota? Never heard of that.

 

[troverman]

Temps 20s to 30s now. What got my attention was the engine did not turn over near as fast. Started but seemed
Like it struggle.

Yup, no manual operation to the glo plugs....full auto. I guess if i want to try and eliminate one critter i could change to a lighter weight oil and see what happens. We can get pretty cold weather here, so a block heater would help come Jan and Feb. Guess i will scratch head couple days and see

Thanks for posting

I'm not sure the lighter oil will change things much. My L4310 had 15w40 oil in it last winter AND started normally. It is a 2002 and had the original battery (replaced it this past summer finally). No block heater, no battery tender.

Makes me think maybe your battery was / is bad. Slow starting can also be the starter, too...although a failure this early on would seem unlikely.

 

[Smokeless]

....Makes me think maybe your battery was / is bad. Slow starting can also be the starter, too...although a failure this early on would seem unlikely.

That was my first thought. Removed battery and had dealer load test. Tested ok. Maybe starter, dunno. Cleaned up battery connections and will check ground connections today.

If ok, i guess i could check starter amp draw, but it turned over fine in warmer weather.

 

[North Idaho Wolfman]

Make a quick video of it cranking and starting, post it on youtube and give us a link to see it, then we might be able to give you a better determination if you have a real issue or not and where to go next.

 

[Smokeless]

Make a quick video of it cranking and starting, post it on youtube and give us a link to see it, then we might be able to give you a better determination if you have a real issue or not and where to go next.

Will do, suppose to be nearly 60 tomorrow, then maybe few cold days comimg. It will take a day or two since playing weather, but will do. Thanks

 

[Sparky73]

Thats a great testimonial. My new 3901 has no option (as I can tell) to turn on glo plugs and hold for a few seconds. First turn of ignition turns systems on including glo plugs and they shut off pretty soon by some timer somewhere.

Mine has never failed to start, i was just a little taken back by how slow it turned over. Could be oil thick enough slow it down, just changed it at 49 hrs, sitting on 74 now.

Sounds like you have a good one

Have you tried turning the key towards start but not far enough to engage the starter? That's how my B2650 glow plugs are activated. Just hold it there for a few seconds and then cranks right up. I've never held it until they go out but I suppose that would work just like the 'ol truck glow plugs.

 

[troverman]

Have you tried turning the key towards start but not far enough to engage the starter? That's how my B2650 glow plugs are activated. Just hold it there for a few seconds and then cranks right up. I've never held it until they go out but I suppose that would work just like the 'ol truck glow plugs.

That's not how his system works. He turns his key one click like he stated and the glow system will heat until the computer determines there is enough heat in the cylinders to start and run cleanly. Then the light goes out. On the B-series, you have to hold the key against pressure and the light stays on until you release it. It is not automatic; you could hold the key on forever and it would continue heating until the battery died. You can also re-activate the glow plugs after the engine starts by turning and holding against pressure again.

 

[Dave_eng]

Temps 20s to 30s now. What got my attention was the engine did not turn over near as fast. Started but seemed
Like it struggle.

Yup, no manual operation to the glo plugs....full auto. I guess if i want to try and eliminate one critter i could change to a lighter weight oil and see what happens. We can get pretty cold weather here, so a block heater would help come Jan and Feb. Guess i will scratch head couple days and see

Thanks for posting

Sent you a PM

Dave