What's wrong with my tractor? Engine? Injector Pump?

   / What's wrong with my tractor? Engine? Injector Pump? #1  

npaden

Platinum Member
Joined
Mar 8, 2006
Messages
582
Location
Lubbock, Texas
Tractor
2011 LS U5030C
I was out brush hogging some tall weeds today with my Kubota L4200 (45hp diesel - 1996 with 1,050 hours) and was giving the old girl a pretty good workout. Nothing she hasn't done before but a workout all the same. Going through some Russian Thistle and Careless Weeds 5 to 6 foot tall. Mowing with a medium duty 6' rotary cutter.

I mowed around the house this morning and didn't notice anything unusual. Went after the weed patch (about 4 acres) and she knew it was going to be work but nothing really rings a bell about her performance at first. I had to drop her down into 3rd Gear on some really thick Russian Thistle but that didn't seem completely abnormal. She was running a little warm but I figured that was due to the weed seeds and I needed to watch the radiator screen and keep an eye on the air filter. I did run her low on fuel, not completely out, but she acted like she was going to stall so I idled her down and turned her off. Went and got some diesel and got back to work but she was running warm again so I turn her back to the house and cleaned up the radiator screen and checked the air filter. It wasn't really bad, but had some seeds in it. I got back out there and she was still running warm - generally she runs at about 1/3rd on the temp gauge and she was running 2/3rds - not up to the hot but still above normal. I was now having to downshift on some fairly light stuff, and I couldn't keep the cutter spinning in 5th gear at all which is my normal gear that I use for mowing.

I thought it could be the mower, so I double checked the gear box on the cutter and it had oil in it but I topped it off just for good measure. I could turn the cutter by hand fairly easy so it seemed to be okay. The gear box was warm, but not excessively hot. I cleaned the radiator screen and hosed off the radiator and double checked the engine oil and coolant and everything seemed okay. I figured I'd go ahead and finish the last bit. It seemed to do better but still didn't have the guts that I would normally expect her to have. I had to downshift in some light stuff a few more times and at the very end I ended up all the way down into 2nd gear which is absolutely crawling. I noticed more smoke that usually from the exhaust when she was really giving it her all. Kind of a blue tint to it but not much. The color you would expect from a tractor really giving it's all, but I was mowing light grass and was in 2nd gear. I figured it had to be the gear box on the mower. I finished up and took her back to the barn.

I checked her over and let her idle awhile and when I went to shut her down the key wouldn't turn her off. That means that I blew a fuse but that's an easy fix.

To help me decide if it was the mower or not I took it off and hooked up my tandem disc. I normally pull it in 5th gear as well. The tractor had cooled off and I took it out and started discing. Pulled it pretty well in 5th gear for about 5 minutes and then the temp started climbing again. It wasn't hot out today so that couldn't be the issue and I've run the tractor hard for hours and hours when it was hot outside without any issues. After 5 minutes she started to act gutless again and wanting to bog down so I had to shift into 4th gear to pull the disc engaged. About 10 minutes into it she was all the way back up to 2/3rd on the temperature gauge and working hard to pull the disc in 4th gear. It seems that the problem is with the tractor, not the mower. I went ahead and picked up the disc and ran the tractor back to the barn. I let her idle down again and checked her over again and nothing seemed obviously wrong. She's not really smoking on the exhaust except when she seems to think she is under heavy load. No unusual knocking noises or anything like that. I'm at a loss to what could be wrong and am not excited about taking her to the dealership for them to poke around because I really don't like the local dealer.

Based on my description is there anyway to figure it out?

Thanks in advance. Nathan
 
   / What's wrong with my tractor? Engine? Injector Pump? #2  
Keep in mind I am not a diesel mechanic, but it could be your fuel filters are clogged. Have you checked them?
 
   / What's wrong with my tractor? Engine? Injector Pump? #3  
I would replace the fuel filter?filters; running lean could cause your heat. Maybe time for a coolant flush. Use coolant for a diesel. Hows the air flow through the radiator?
 
   / What's wrong with my tractor? Engine? Injector Pump? #4  
When you cleaned the radiator screen, did you just pull it and wipe off the gunk? If so, you need to take it all back off and hose out the radiator. A good long hosing getting each little area from both sides. Let it dry and it should be all better. After a while the fins clog and you get your exact symptoms.
 
   / What's wrong with my tractor? Engine? Injector Pump? #5  
Maybe it's time for a new air filter as well? A diesel starving for air will bog it down and cause overheating. Air flow restrictions can also cause oil mist to be sucked in from the crank past the rings into the combustion chamber, maybe thats where the little hint of blue smoke is coming from? Good luck with it.

Larry
 
   / What's wrong with my tractor? Engine? Injector Pump?
  • Thread Starter
#6  
Thanks for the input.

I ended up calling a friend who is a tractor mechanic last night before I got any replies and you guys pretty much mirrored his suggestions. I was afraid something major was going wrong with the tractor, but he said that 90% of the time what I'm describing is either the fuel filter or the air filter. He also recommended a cleaning of the radiator but suggested using compressed air instead of a hose if possible. I'm going to pickup the filters today and hopefully that's the problem.

I've got a big list of chores for her this weekend!
 
   / What's wrong with my tractor? Engine? Injector Pump?
  • Thread Starter
#7  
Well I changed the filters and cleaned the radiator out really good with compressed air. The fuel filter was dirty but not clogged by any means. Same with the air filter. The radiator wasn't that bad either.

Started her up and ran her with the disc again. Pulled great in 5th gear for about 3 minutes then started bogging down again. It started smoking a bit and I put her into 4th gear and pulled for another 3 or 4 minutes and it started bogging in 4th gear and smoking steady.

I guess the next step is to take all the fuel lines off and make sure they aren't clogged?

The way it acts there must be fuel in the system to start and then it works harder and harder to get fuel and it just can't keep up.

One other consideration is that after I changed the fuel filter and opened the bleed valve on the injector pump I never could get it to actually leak fuel out the bleed valve.

Is this looking like a bad injector pump?

Thanks, Nathan
 
   / What's wrong with my tractor? Engine? Injector Pump? #8  
Owning quite a few tractors myself, and spending countless amounts of money on filters 典hat痴 weren稚 needed yet and other items used in troubleshooting. One thing that comes to mind that you should check is the radiator.

Your problem has happened to me twice now on two different tractors and both times resulted in radiator problems with plugged cores.

Troubleshooting is easy. It cost me a fortune to watch the Case dealer do it.

Make the Radiator fins access able with your bare hands, either front or back. Front preferred, Start and run the tractor until it gets hot, or the problems you are having, then shut the tractor down, and run your hand across the fins of the radiator. If it is cool in the outside edges and very hot in the center, then you have plugged cores and the radiator needs to be replaced or rotted out. The radiator must have temperature distributed equally throughout the core. IF the Radiator is cool and you feel very little heat, then replace the thermostat. These guys get stuck closed as well as open.

If any work is done to the cooling system, NEVER put tap water in the radiator, Always use a 50/50 blend of antifreeze, or if you dilute your own use Distilled water, like you would a battery. Tap water, well water, etc has organisms in it that activates when temperatures change from hot to cold and this is the main cause of plugged cores.

So before doing dumping anymore money in to it or bringing in a mechanic, give this a shoot and see where it leads you. Can稚 hurt and costs nothing
 
   / What's wrong with my tractor? Engine? Injector Pump? #9  
Well I changed the filters and cleaned the radiator out really good with compressed air. The fuel filter was dirty but not clogged by any means. Same with the air filter. The radiator wasn't that bad either.

Started her up and ran her with the disc again. Pulled great in 5th gear for about 3 minutes then started bogging down again. It started smoking a bit and I put her into 4th gear and pulled for another 3 or 4 minutes and it started bogging in 4th gear and smoking steady.

I guess the next step is to take all the fuel lines off and make sure they aren't clogged?

The way it acts there must be fuel in the system to start and then it works harder and harder to get fuel and it just can't keep up.

One other consideration is that after I changed the fuel filter and opened the bleed valve on the injector pump I never could get it to actually leak fuel out the bleed valve.

Is this looking like a bad injector pump?

Thanks, Nathan

Here is the checklist if this were a JD...:rolleyes:


Engine Does Not Develop Full Power
1.Air cleaner restricted
2.Low cetane fuel
3.Incorrect timing
4.Diesel automatic advance is faulty or not operating
5.Filter clogged
6.Air leak on the suction side of the system
7.Injection nozzles return lines clogged
8.Injection nozzles faulty or sticking
9.Injection pump return fuel line or fittings restricted
10.Injection pump housing not full of fuel
11.One or more connector screws obstructed
12.Water in fuel
13.Injection pump 180 degrees out of time
 
   / What's wrong with my tractor? Engine? Injector Pump? #10  
That sounds like a clog in the tank or line to me.
 
 
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