Cold Weather Pre-heat and other questions

[Texasmark]

I have the 1" thick, comprehensive Owner's Manual but this isn't covered specifically. The manual covers the fact that On position is also Pre-heat position, and mentions an indicator in the dash panel but not this specific question.

My precious tractors had a dash "Pre-heat" symbol illuminate when the operate switch was moved to the ON position from OFF when the temperature was below a certain value. The light was timed and when extinguished, you roll on over to Start and go.

The MT225s just winks at you when going to the Pre-heat position my first morning in having it and in trying to start it, it winked at me when going to On position rather than stayed illuminated. I figured I didn't need to wait since it extinguished, rolled over to Start and it took several 2-3 second start-wait-start-wait cycles before the engine came online.

Question is, is it normal to wink and you just guess at how long the key stays in the On position before your roll on over to Start?
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Operators manual states that idle RPMs on Hydros (my first tractor, my mowers are hydros) are over 1200. Mine idles at around 1600. Said it needed to be high to get the oil flow adequate to have decent performance at lowest speed. Yes, no?
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Comments appreciated.

 

[Bearsixty7]

You just have to get a feel for it.
I see you're in NTX and normally we don't get that cold, however yesterday/today we are below freezing. I have never needed to start mine when this cold but I have noticed on my MT240 the glow plug light will stay on longer when it's colder weather. I would think yours should as well.
However, you can just give it more time in the "Warm" or glowplug on position before trying to start it.

I saw a few people mention that if you turn the key to the left or CCW and hold it, that the glow plugs will come on for the warm up. My manual doesn't state this and since the glow plug light comes on for a short time when I turn to the right, I always just did that. But being the curious person I am, I tried turning the key left once and sure enough, the glow plug light came on, I held it there probably 15 seconds and it stayed on until I released it. You can try that as well.

 

[Texasmark]

I forgot about the CCW...will give it a try when I go outside in a few minutes. I had that on a MF 35 years ago but Fords, my current older tractor inventory has it in the CW position. Do appreciate your time sir.....and yes it was chilly this AM.

 

[Texasmark]

I checked it today and it does turn on the plugs either direction but the wink still exists. I heard the glow plug relay energize when switch switching to the function and immediately turn off, in both directions. It was about 40*F in the shop this AM. I'm starting to think that it isn't cold enough for it to stay energized.

Initially I'd only roll the starter for a couple of seconds and stop. Today I rolled it longer and it hit in around 4-5 seconds. The owner's manual caution is for rolling quite a bit longer than that so maybe that's a hint that I wasn't used to how long it takes cold. I will say this. My Branson 2400 was Swirl Chamber and had the glow plugs present at much higher temperatures on a cold start. It always started with a few puffs of smoke. This one is an IDI ignition, don't know if it's indirect injection (as is swirl chamber) or Independent Injection like care/trucks with MPI. Looking into that this evening.

I will say this. For a 235# 6'5" guy, that little sucker is mighty easy to enter and exit. The human factors engineers on the design team really did their job. I already see that I sold myself short when I bought the Branson as stick shift. I should had bought it as a Hydrostat and I'd probably still have it......but it doesn't let you in and out as easy and that item is high on my list of wannas.

 

[870m]

I also own a ls mt2 25s and im not
At all that pleased with its cold weather starting . I find myself cycling the key 9 ten times and still not enough to get a strong start. I consider this a design flaw by ls. Everything else about this tractor is fantastic, by the way its 17 degrees outside im in N.E.

 

[wraven]

I also have a MT225s and also wondered why there was not a glow plug light that stays on until ready. I just leave the key turned to where the glow plug indicator is for about 10 seconds and then turn to start. I’m in South Central PA and it hasn’t really gotten that cold this year to give me any issues.

 

[nicksdad50]

Hi Guys. I am out of west NJ near Easton PA. I have experienced over the last year with my M225s so vey cold mornings (10-15 deg). I have always just placed in the on position counted to 10 and she starts up. I had one day where she sat for close to a week last winter if sub 20 deg days that I had to wait for the sun to come up and warm her up a bit before she started. I have since always added Seafoam to my diesel.

 

[mred2]

I am following this as I have an XR4150 and the light stays on longer if it is colder. Summer on a second or two. Yesterday, about 10 seconds. Hard to believe they would take that out of a newer tractor to save a few cents.

 

[JCoastie]

@mred2, They haven't on my MT240, this is from the manual and seems accurate as far as I can tell with my moderate (30's F) temps.

 

[rodneyn]

I知 in northern Indiana with MT225S I agree the glow plug sequence is short wink of the eye. I have also noticed when turning key on to start motor the glow plug light comes on as the motor is cranking. I run 5w-20 rottella syn-blend it makes difference in the cold. I do agree it will smoke you out when first starting in extreme cold. It starts a lot easier then my Kioti Lk3054 which requires compression relief cable to start in cold weather. Suggest if running in cold weather use oil heater or inline heater in on radiator hose. Warmer the motor less issues to address in the future. Diesels don稚 like sub- zero weather.

 

[PCABE5]

I am following this as I have an XR4150 and the light stays on longer if it is colder. Summer on a second or two. Yesterday, about 10 seconds. Hard to believe they would take that out of a newer tractor to save a few cents.

I think your seeing the difference between ECU controlled preheat and the older timer circuit on the MT225.

 

[Doofy]

@mred2, They haven't on my MT240, this is from the manual and seems accurate as far as I can tell with my moderate (30's F) temps.

View attachment 685013

Interesting little chart. Going to time my XR3135 to see if it works the same way.

 

[Underdog57]

My 2013 pre-emission Engine , The plugs are on a timer, doesn't matter what the temperature is. I don't know how long, guess I should time it sometime!

I would strongly suggest putting an inline coolant heater in, cheap & easy install. It makes a big difference, today it was 15* and mine was plugged in for 4 hrs. and started so easy. I have a timer come on at 8 am and off at noon. If I think I will use the tractor the next day I plug it in the night before.

 

[Avenger]

I'm guessing that North Texas doesnt get cold.

Now before you flame me, I know what your going to say: "It does too! the lows are below freezing!"

To a diesel, thats not cold. Dipping blow freezing for a few hours, or staying at 30-35F for the day, is simply not cold. It might feel cold to you, but to a healthy diesel engine, that's not cold.

The ECU checks the engine temp before startup to determine how long to keep the glow plugs on for. The colder the engine, the longer the glow plugs need to stay on. The longer, obviously, the warmer. But how warm does it really need to be inside that combustion chamber? Not very, but warm enough. And the ECU expects that you will command the engine to start RIGHT as the glow plug light goes out.
I experienced a cold start recently (before the recent engine heater install). It was cold out, like 12*F. I turned the key warming the glow plugs, while I waited, I pushed in the clutch and locked it, and then realized I forgot a new roll of paper towels I use to check the engine oil. (I typically keep a roll of paper towels inside the cab for checking the oil). I ran into the garage and grabbed a roll, checked the oil, reached in and cranked the key. But by that time, the glow plugs shut off and the combustion chambers quickly cooled. When I started it up, it was rough! It took several seconds to smooth out and run normal. I should have let the glow plugs fire again.

When you turn the key, the glow plugs start warming up. The dash goes though its cycle, all lights on, tach runs check, etc. and the light that remains lit is the glow plug light. That cycle takes a few seconds. So a "wink" is probably more like very slow blink. Like a child falling asleep that doesn't want to.

So why not have the ECU run those glow plugs until the combustion chamber is HOT!? Simple, the glow plugs wear. They burn up if left on too long. Story time:
Back on the farm, in my youth, we had old equipment. One tractor we had, had an old push button on the dash for the glow plugs. I was taught the startup sequence: Check oil, make sure it's in neutral (no safety switches though), push in clutch, hold glow plug button down for a 30 count, turn key. But when that button died, my grandpa made an alligator clip for the battery, which was located next to the seat. New startup sequence: check oil, neutral, place alligator clip on batter terminal, wait for 30, turn key... forget to unhook alligator clip.
We would usually remember several minutes after startup, curse at ourselves (grandpa was the worst), and go about our day. Until we starting having cold starts. Grandpa told me that since we cannot seem to remember to unhook the alligator clip from the battery, we need to replace the glow plugs. We then set out to do this rather big job (we did other things to this tractor too, while it was in the shop, like replace a simple push button on the dash) That's when I saw the difference between a burnt up glow plug and a new one. Big difference. All because the glow plugs ran longer than necessary.

In short, the ECU ensures the glow plugs only run for the correct amount of time assuming you start the tractor (as you should) as soon as the light on the dash goes out.

 

[870m]

All things been said im gonna have to find a work around this the hose heater might be doable but would require that the tractor be parked up at the house, to cold now but come spring i will dig into the glo plug circuit and see if mods are possible. I can see this being a long term problem for me, here in New England.

 

[LouNY]

One issue I have found with these "smart" glow plugs or intake manifold heaters,
when you use a block heater or any type of heater that warms up the water the heaters do not run.
Case in point it wasn't that cold this morning (12F) but the tractor was plugged in for about 4 hours before I started it.
When my tractor is cold the controller will run the intake heater for several seconds before the light clears and you can start it,
it also keeps the heater turned on for several seconds as the tractor runs, it makes for a nice smooth start.
This morning with the water warm it didn't want to run the heater, I cycled the key several times (4 or 5) and she started right up,
but it wasn't the nice smooth run it was a rough run for about 5 seconds before she smoothed out.
I have been telling myself to buy another temp sensor and wire in a double pole switch so I could select the water jacket or ambient temp for the heater control.

 

[nicksdad50]

Hi Guys. I am out of west NJ near Easton PA. I have experienced over the last year with my M225s so vey cold mornings (10-15 deg). I have always just placed in the on position counted to 10 and she starts up. I had one day where she sat for close to a week last winter if sub 20 deg days that I had to wait for the sun to come up and warm her up a bit before she started. I have since always added Seafoam to my diesel.

Follow up:

With the heavy snow and cold weather I needed the tractor checked the ccw position and yep it lights the glow plug light (blinking) and after about 10 seconds it stopped. I then rotated to start and she started right up. I haven’t checked and have never read my manual. Tried too but found it useless.

 

[Texasmark]

PCABE5 and Avenger, I think you guys nailed it. The dealer says it stays on for about 15 seconds. My S has an ECU and the wink on the dash may be telling me that the Pre Heat circuit has been activated. The click I heard, thinking the Pre Heat relay was de-energizing, may have just been the light with the PH still functioning. So, I tried leaving it in ON or in the CCW position for a few seconds and in rolling the engine over it lit right off.....so I do believe, unlike my previous Branson, it does function differently with the same result. We'll see as this week, like lots of folks it will be cold here for us (down to +13F) about 4 days and that will tell me what I want to know. I'll tell you, I really do like it. I took a beating on price selling a never spent a day out of doors, 4 year old tractor/loader with 400 hrs because of a few quirks it had that annoyed me but the money is spent and I am enjoying the proceeds every day.

 

[Texasmark]

Well, N. Texas at my house is 7*F right now and never in my life did I expect to see this especially with "Global Warming" which at least one forecaster said that "this cold snap has nothing to do with GW". Well where is the ice that had to be somewhere to get this kind of blizzard....though GW melted the Poles......

Anyway I was thinking about the Texas Power Grid and wondering how it was holding up to this cold wave and on to thinking about my stored diesel gelling as I filled up with #2 last fall and have PS performance additive, but not the anti-gel additive. In the process of surfing, I came across a NAPA site that answered my question about gelling temp and all.

They also had several items of interest on the site and one included this:

"The modern diesel engine glow plug looks similar to a pencil soldering iron and functions on similar principles. The glow plug is threaded into the cylinder close to the fuel injector port and is powered by a dedicated high-current circuit. When commanded on, such as pre-start warming or when emissions control strategies demand, the glow plug痴 internal heater coils heat the tip to glowing orange to red-hot. While older designs needed 20 to 30 seconds to heat up, modern designs need as little as six seconds."

So with that, and my going out just to check the speed of my pre heat ON-OFF cycle with 30 degree temps in the shop, I noticed that the pre heat coil did stay on longer, so the ECU temp sensor is controlling the glow plug as it should and that there is nothing wrong with my 2020 year model pre heat circuit. So, as the dealer said, for colder temps, just cycle the pre heat several times and she will light right up...like one or two seconds on the starter.

 

[PCABE5]

Good news on your glow plugs. For Texas that is cold.