Black smoke on cold start

[awesome]

Hi everyone,

I have a 2yo BX23s with 255h on it.
The last few times I tried to start it up, in cool weather (-10c), I use the glow plugs for about 30sec and give it a start. The tractor starts but it starts to emit black smoke and starts reving like crazy. If I don't turn it off, it just keeps on turning faster and I'm afraid the engine would blow.

I'm using regular diesel with no additive (other that what they might put in during the winter at the pump).

It seems like if I start it warm, using the block-heater, then I don't get that problem.
Any idea what is going on? Is this normal? Should I get it checked? I guess this would be part of the 5y warranty on the engine?

 

[Russell King]

That is dangerous and can ruin your tractor and possibly kill you when it comes apart.

It is getting fuel with no govern control of speed.

Get it fixed

 

[North Idaho Wolfman]

Sounds like you have a failed injector.

Yep take it in and have it checked out.

 

[awesome]

Thanks for the info. Should that be covered under the powertrain warranty?

 

[BruceP]

It sounds to me as if the engine speed governor is stuck open when cold. You were smart to shut it down before damaging engine.

Recall that the throttle-lever DOES NOT control engine-speed... it really controls the DESIRED engine-speed...it is the governor which controls the engine-speed. If the governor 'thinks' the engine-speed is below the desired, it will hold the throttle WIDE OPEN until engine-speed is attained. (In your case, the flywheights of the governor are not working as expected to slow down the engine when it gets to desired RPMs)

Since this only happens when cold, it may be difficult to duplicate at the shop. It may be easier to simply replace the entire governor assembly (but costly) Obviously, something is sticking/binding when it is cold.

 

[awesome]

So I just tried it this morning after leaving the block-heater on for 30min and I still had the same problem. It was -12c outside this morning.

Would that still be consistent with the defective governor theory?

 

[85Hokie]

So I just tried it this morning after leaving the block-heater on for 30min and I still had the same problem. It was -12c outside this morning.

Would that still be consistent with the defective governor theory?

Whatever the problem may be - the dealer should solve BEFORE something occurs that can be blamed on the user.

I would take it to the dealer - or have the dealer pick up ASAP or sooner!

 

[awesome]

understood. I called the dealer. Thanks for the info.

 

[mikester]

Is it parked outdoors? Maybe a water/ice infiltration issue on the linkages.

 

[awesome]

It's under a carport. Altgough I do get snow on my seat, I don't think it would be an issue under the hood.

I'm getting a service call today. I hope I don't have to get it towed. I'll update the thread.

 

[awesome]

I had the tractor brought to the dealer and they came back to me with a charge of 1000$. They say that condensation was building up in the injection pump andthat usually happen when working the tractor too fast without letting it warm up enough when it's cold.

I find that very strange because I do let it warm up. Maybe not 15minutes like they require.

1000$ down the drain!

 

[nbryan]

I had the tractor brought to the dealer and they came back to me with a charge of 1000$. They say that condensation was building up in the injection pump andthat usually happen when working the tractor too fast without letting it warm up enough when it's cold.

I find that very strange because I do let it warm up. Maybe not 15minutes like they require.

1000$ down the drain!

So they had to replace the injector pump then? That's a big bill!

 

[awesome]

So they had to replace the injector pump then? That's a big bill!

No, they just took it apart and cleaned it. I just hope it wont happen again.

but does that even make sense? To have an issue like this if you dont warm up the tractor enough?

 

[sheepfarmer]

It doesn't make sense to me offhand. The only thing that jumps out at me is 30 seconds is an awfully long time for the glow plugs. What does your owners manual recommend for glow plug time and throttle position for cold weather starting?

 

[whitetiger]

No, they just took it apart and cleaned it. I just hope it wont happen again.

but does that even make sense? To have an issue like this if you dont warm up the tractor enough?

It makes absolutely no sense at all. There could possibly be condensation under the pump, but not enough to freeze and open the pump to wide open. Once the engine is up to operating temp, it should boil the condensation and dissipate it.

 

[North Idaho Wolfman]

Yea I agree, sounds like a bunch of poppy cock to me.
I've never heard or seen such a thing as condensation in an injection pump causing a runaway issue.

 

[Dave_eng]

Is there any chance that this owner's problem could be related to the Product Improvement Campaign AG03616-L60 ( possibly the BX series had a different campaign number) dealing with freezing Crankcase vent systems. On some engines the frozen vent forced crankcase oil up the turbo drain line and the engine would runaway on crankcase oil.

There were previous posts on this topic.

Campaign

Ottawa Canada has had very cold temps this winter.

Whitetiger and NIW are the experts, I am just recalling a conversation with a Kubota tech who was doing these recalls in my area.

Dave

 

[awesome]

That's interesting. Initially, the guy told me it he heard a bout a campaign for the bx series about an issue similar to this. But it turned out not to be the case and instead it seems it was my fault.

I just dont understand how water gets in there if there are filters in place for this. And if water does get in there, enough to cause an issue, they it would be a bad design no?

I'll test the tractor daily and if I get the issue again I'll call them back.

But one last question: leaving aside the runaway issue, is it normal that when starting the tractor in cold condition it would bog (not sure if "bog" is the right term here) and output black smoke? Because it still does that right now.

 

[Tornado]

That's interesting. Initially, the guy told me it he heard a bout a campaign for the bx series about an issue similar to this. But it turned out not to be the case and instead it seems it was my fault.

I just dont understand how water gets in there if there are filters in place for this. And if water does get in there, enough to cause an issue, they it would be a bad design no?

I'll test the tractor daily and if I get the issue again I'll call them back.

But one last question: leaving aside the runaway issue, is it normal that when starting the tractor in cold condition it would bog (not sure if "bog" is the right term here) and output black smoke? Because it still does that right now.

So you actually paid the $1,000 for them to do this "cleaning" ?

 

[awesome]

We negotiated 600+tx . Although that includes 150 for transport.
What can I do ... by that time I was already upset by my oven that also broke during the same week and had to pat 400$ to get it fixed.