LB2204 Cold Starting

[RandR10]

So I've been having trouble cold starting the tractor even after the rebuild. It'll fire right away after a glow plug cycle but run really rough for about 30 seconds before it smooths out and runs properly. Very smoky exhaust before it smooths out too. Doesn't seem to matter much what the outside temp is, it always does the same thing if it's been sitting awhile. Sometimes it'll stall a couple times and I'll have to re-cycle the glow plugs to get it to rev up and smooth out. Thereafter it runs like a top and has plenty of power. If I shut it off and restart while it's still warm, it fires right up and runs smooth right away. This leads me to look at glow plugs.

So I took a look at my glow plugs today and I'm getting just a hair over 1 ohm on every plug, which looks pretty normal to me, so I decided to check voltage at the terminals when the glow plugs are cycled. I was surprised to see only 7 volts. Is that normal? It climbs a little as they're left on, and I can clearly see the indicator coil in the dash glowing too, but this is a 12 volt tractor, so I don't understand why I'm seeing voltage that low. I'm just trying to figure out if I have a wiring issue or if this is normal voltage to be seeing.

By the way, the battery has plenty of juice and the engine is turning plenty fast. It'll crank and crank if I ask it to.

 

[grsthegreat]

You need to get the battery load tested. I just replaced the battery on my DK45 for almost the same problrm. Tracyor turned over, but glow plugs not getting juice. I load tested the 900 cca battery, it tested at 380.

i replaced battery and its back to its old self. Fires up great.

 

[Robin Veerman]

How fresh is the fuel? Do you know what the cetane rating is? Ask the attendant….if they even know what you’re talking about. Switch to another depot and preferably one with good turnover. Or add a quality cetane improver. I’ll bet that you’ll notice an improvement, barring any other issues. It does sound like you’re breaking it in though. Give it a good workout if you can.

 

[RandR10]

You need to get the battery load tested. I just replaced the battery on my DK45 for almost the same problrm. Tracyor turned over, but glow plugs not getting juice. I load tested the 900 cca battery, it tested at 380.

i replaced battery and its back to its old self. Fires up great.

Thanks I'll look into that.

 

[RandR10]

How fresh is the fuel? Do you know what the cetane rating is? Ask the attendant….if they even know what you’re talking about. Switch to another depot and preferably one with good turnover. Or add a quality cetane improver. I’ll bet that you’ll notice an improvement, barring any other issues.

Fuel is just a couple weeks old. I ran almost all the old fuel through it before refilling with fresh stuff. Didn't seem to make any difference when the new fuel went in. Not sure what the cetane rating of it is.

 

[RandR10]

I don't have access to a load tester right now. Pretty sure I'm on the tail end of covid and don't want to spread it around, so I'm stuck home for the next few days until I'm completely over it. Anyway, I did check voltage across the terminals and I've got 12.5 volts, and that's after cycling the glow plugs a few times. Also, like I said, it cranks really well, and doesn't slow down at all if it doesn't start right away. Pretty sure the battery is tip top. The question remains, is that 7 volts I'm reading at the glow plugs normal?

 

[grsthegreat]

Place the voltage tester on the battery and watch the valuse on the battery voltage when cycling glow plugs. If battery voltage also drops into the 7s, that would explain whats happening.

 

[RandR10]

Place the voltage tester on the battery and watch the valuse on the battery voltage when cycling glow plugs. If battery voltage also drops into the 7s, that would explain whats happening.

Voltage at the battery terminals drops to 11.8V when I hit the glow plug switch.

 

[RandR10]

So I've done some more research and just expanded my search to Kubota stuff since this tractor is so close to the L245. Looks like 6-7 volts is normal for these systems? I'm thinking I'll look at fuel system next. I might have a leak in the hard lines and I'm getting air ingress.

 

[Robin Veerman]

After the rebuild did you time the fuel pump by chance.

 

[grsthegreat]

Than the battery looks good. Very weird. Sure seems like a glow plug issue.

 

[RandR10]

After the rebuild did you time the fuel pump by chance?

Yes. Cams for both the valves and injection pump were timed when the engine was reassembled.

 

[JoelD]

When I start in cold I cycle glow plugs then when I start tractor I flip key back and power glow plugs, helps to smooth out faster.

Although 30 seconds is a long time regardless

Maybe compression?

Joel

 

[RandR10]

When I start in cold I cycle glow plugs then when I start tractor I flip key back and power glow plugs, helps to smooth out faster.

Although 30 seconds is a long time regardless

Maybe compression?

Joel

If it was compression I'd be very surprised. Brand new sleeves, pistons and rings. Lapped the valves in before reassembly too. I noticed last time I was in there messing around with the hydraulics a little bit of fuel collecting on top of the injection pump. That's gotta be the problem. When I pulled the motor a lot of fasteners were completely loose, including in the fuel system. I didn't have the injection pump apart but I wouldn't be surprised if it's been tinkered with and not torqued back down properly. I'm probably going to go through that next since everything seems to check out on the glow plugs.

 

[Username Taken]

Mine doesn't run rough for 30 seconds, but it definitely runs rough for 15-20 seconds. I think it's just the IDI pre-combustion and the injectors and the fact that it's 1930's technology.

I love it.

 

[RandR10]

Mine doesn't run rough for 30 seconds, but it definitely runs rough for 15-20 seconds. I think it's just the IDI pre-combustion and the injectors and the fact that it's 1930's technology.

I love it.

Thanks for the insight. It's helpful to me because I've never wrenched on a 3-cylinder diesel tractor engine before this one. I had a 7.3 IDI powered box truck for about a year a couple years ago and that one when everything was dialed in and working properly would fire instantly with no roughness to the idle. When I sold it, it had been setting for 4 days on a 40 degree day it fired right up like this after I let the glow plugs cycle. I guess maybe that's a bit much to ask for with this particular setup? Maybe 3 cylinders is a bit harder to get spinning fast enough vs. 8?

 

[Username Taken]

Thanks for the insight. It's helpful to me because I've never wrenched on a 3-cylinder diesel tractor engine before this one. I had a 7.3 IDI powered box truck for about a year a couple years ago and that one when everything was dialed in and working properly would fire instantly with no roughness to the idle. When I sold it, it had been setting for 4 days on a 40 degree day it fired right up like this after I let the glow plugs cycle. I guess maybe that's a bit much to ask for with this particular setup? Maybe 3 cylinders is a bit harder to get spinning fast enough vs. 8?

My brother had one in his F-350. Hated it so much I loved it. Gutless, smelled, rough. The good old days.

I was a little taken aback by how much my Kioti spit and sputtered in fits and farts when cold. Bur I was told it's normal by several people. I'd like to be able to tell you it gets better but it really doesn't until it's warmed up -- A lot. I wonder if some of it is piston slap. I would think that with Daedong's experience in machining quality blocks and heads for decades, they'd be state of the art. Maybe they use 'barrel-shaped' pistons.

I stopped worrying about it

 

[Robin Veerman]

Here’s a picture of Amsoil Cetane boost, with some info, that I use. You should try a Cetane boost of your favourite brand and see if it doesn’t make a difference. Diesel needs to be over 50 cetane to ignite/burn efficiently but it’s generally not even close. Hopefully the picture opens…

 

[AWSubie]

One method for troubleshooting diesel starting issues is to buy an inexpensive RPM tester.

Diesel engines require about 200 rpm for reliable starting. Even when the engine sounds like it is spinning fast enough, it is difficult to tell whether it is, if you don’t have a tester.

In cold weather, diesels need a battery that is in above average condition.

 

[RandR10]

A little update on this. While troubleshooting (and fixing) my hydraulic issue, which I'll talk about in my other thread, I found a pretty bad leak in the fuel bowl valve. Tried to fix it with a new o-ring but it still leaks. I'm thinking corrosion must have caused pitting in the housing and I'll have to replace it. Definitely a good way for air to get into the fuel. I also pulled off the little nuts on the top of the injection pump and replaced the o-rings on those while I was in there, so hopefully the fuel system won't have any way for air ingress. I'm thinking that's got to be my issue with starting. I'll give an update when I get the new fuel bowl assembly and put it together.