Tractor dieing after 15 min of work

   / Tractor dieing after 15 min of work #1  

rogue909

New member
Joined
May 21, 2014
Messages
3
Location
Houston, Tx
Tractor
BX22
This is a bit of a read, so I appreciate all who comment.

I'm going to start by saying we have 2 Kubotas, one of which is an older M4030SU and the other is a much nicer BX.
The M4030SU was purchased on the cheap and was our first tractor - the oil rings were going out and it had lots of blow by. The owner told us it would need to be overhauled. Seeing as it was our first tractor it was a good deal, we got to figure out whether a tractor would actually be of use to us and it didn't cost us a fortune.
That was 10 years ago, we got our moneys worth out of the M4030 and purchased the BX to do some stuff that couldn't be done with the M4030. We are not as hard on our tractors as most are (we are "weekend warrior" tractor operators) and thus most of our problems & maintenance have been minimal (blown hydraulic hoses, clogged fuel filters, leaky fuel lines, change the oil, etc.)

3 weeks ago the M4030 started overheating while working, it would run for 15-30 minutes then it would get hot. We popped the radiator cap and the fluid was hot. Drained & filled to get it going again.
We got it up to the shed and had a look under the hood and the water pump & fan assembly had clearly failed. The fan was wobbling around instead of rotating. We pulled the water pump off and the bearings must have failed that held the impeller shaft, everything was wobbling around. We ordered a new pump and got it in the mail.
While waiting we decided to clean the tractor up a bit. Took some degreaser to the engine and sprayed it all over, cleaning off a lot of the junk that accumulates over time.
Flooded the inlets & exhausts where the radiator hooked up to clean out any debris that may have accumulated (this is where I screwed up later on..)
Power washed the radiator (with a light attachment) to clear debris & power washed the radiator screen.

We got the new pump in a week later and replaced it (went ahead and replaced the belt at the same time). Filled the radiator up and hooked everything up. And the tractor would not start at all, it seemed the pistons were frozen in place. Then I realized that while cleaning the engine area up, I had flooded the air intake. As a shade tree mechanic typically goes I do pretty good. This is not one of my finer moments.
Pulled the fuel injectors and pumped the water out of the engine. The return hoses got damaged (I'm sure those were the stock hoses that came with the tractor) while I was pulling the injectors so those had to be replaced.

Started the tractor up and it ran great. Went back to work with it and 15 minutes later the tractor died. Pulled the oil stick just out of curiosity and the oil looked terrible (by far the worst oil I have ever seen). Took a pan out and drained the oil. For those familiar with the M4030 it has 2 pans. One of the pans literally poured clear water out for 10~ seconds. A good 5-6 cups of clear water had to have come out of that pan. Sitting for a week with the cylinders full of water with leaky oil rings must have done some bad mojo.
Left the tractor to drain over night and came back the next morning with fresh oil and a new filter. Replaced it all and got it running.

Started the tractor and the same thing happened. Started & ran great. For 15 minutes.
Opened the radiator up & the fluid is warm (120F~) and the engine is a little warmer. Not hot enough to burn a hand but hot enough to be uncomfortable. (It seems to be pumping coolant through the tractor OK)
The fan is pushing plenty of air, it can be felt from either side of the tractor.
Oil looks good (obviously, it was changed an hour ago).
Diesel should be good (otherwise I would think that it would have issues starting).
I'm plumb out of ideas.
 
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   / Tractor dieing after 15 min of work #2  
It could be something as simple as a fuel filter. Have you changed it lately?

Next time, when it dies, immediately loosen the fuel line on top of one of the injectors and turn the engine with the starter, to see if you're getting fuel to the injectors.

Can you turn it with the starter, or is the engine seizing?
 
   / Tractor dieing after 15 min of work #3  
Or, continuing on the simple things note, it could be a plugged fuel cap vent ---- make sure that's clean so the fuel tank doesn't develop a vacuum. If the tank develops a vacuum, it will, in effect, run the tractor out of fuel. Which tractor are we talking about??
 
   / Tractor dieing after 15 min of work
  • Thread Starter
#5  
Which tractor are we talking about??
The M4030, I just edited the original post to clarify that.

I will test the fuel, I've never had problems with the fuel in the tractor so I have done little to it.

The starter turns the tractor with no problem. The starter is relatively new (9 months? a year?) as the original one burnt up. The battery is practically brand new (2 weeks?) so it turns real good.
 
   / Tractor dieing after 15 min of work #6  
The starter turns the tractor with no problem. . .
OK, then the engine is not seizing up. Then, ...

Diesel engines only need 3 things to run: Air, Fuel, and Compression.
You have compression, or it would never start.
So, look at air and fuel.
 
   / Tractor dieing after 15 min of work #7  
Never pressure wash a diesel engine,
especially the injection pump, they run on tight tolerances.
When your machine starts to warm up and this is where your problem is starting,,
leads me to "think' the injection pump may be an issue.
Hope not, could just be air getting into the fuel lines also....
 
 
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